dcsimg
Image of Havard oak
Creatures » » Plants » » Dicotyledons » » Beech Family »

Havard Oak

Quercus havardii Rydb.

Comments

provided by eFloras
Individual clones emerging to heights of 2-3 m from thickets occur sporadically across the Texas range of Quercus havardii and express some characteristics of Q . stellata , such as more deeply lobed leaves and smaller acorns. Such putative hybrids increase in frequency in the eastern part of the range of the species.

Material of Quercus havardii from the Navajo Basin of Utah and adjacent Arizona has been treated as Q . havardii var. tuckeri Welsh. Welsh followed J. M. Tucker (1970) and interpreted these intermediate populations as putative hybrids between Q . havardii and both Q . turbinella and Q . gambelii . Giving varietal rank, instead of nothospecies status, to such populations seems arbitrary, and it certainly is inconsistent with their putative hybrid origins.

license
cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 3 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
original
visit source
partner site
eFloras

Description

provided by eFloras
Shrubs , deciduous, low, forming clones 0.3-1.5 × 10 m, rhizomatous. Bark light gray, scaly-papery. Twigs brown or grayish, 1-2.5 mm diam., glabrous or densely short grayish or yellowish tomentulose, glabrate in age. Buds dark red-brown, subglobose, ca. 2 mm, sparsely pubescent. Leaves: petiole to 7 mm. Leaf blade green, often turning brownish with age, polymorphic, oblong or elliptic or sometimes lanceolate to oblanceolate or ovate to obovate, (30-)50-100 × (10-)20-50 mm, rather thick and hard, base rounded to cuneate, margins flat to revolute, at least some undulate, 2-3 rounded teeth on each side, secondary veins 5-8 on each side, much branched, apex broadly rounded, rarely acute; surfaces abaxially densely grayish or yellowish tomentulose or stellate-pubescent, sometimes only sparsely pubescent, secondary veins quite prominent, adaxially lustrous, very sparsely stellate-pubescent or glabrate, secondary veins very slightly if at all raised. Acorns solitary or paired, subsessile or on peduncle to 10(-18) mm; cup from deeply cup-shaped to goblet-shaped, 10-12 mm deep × 15-25 mm wide, enclosing 1/3-1/2 nut, base rounded or slightly constricted, margin very thin and smooth, scales reddish brown, triangular-ovate to long-acute, proximally moderately to markedly tuberculate, pubescent, often canescent, tips loosely appressed; nut brown, ovoid, 12-25 × 14-18 mm. Cotyledons distinct.
license
cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 3 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
original
visit source
partner site
eFloras

Distribution

provided by eFloras
N.Mex., Okla., Tex.
license
cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 3 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
original
visit source
partner site
eFloras

Flowering/Fruiting

provided by eFloras
Flowering spring.
license
cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 3 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
original
visit source
partner site
eFloras

Habitat

provided by eFloras
Deep, shifting or stabilized sand dunes, off deep sands in putative hybrid populations; 500-1500m.
license
cc-by-nc-sa-3.0
copyright
Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA
bibliographic citation
Flora of North America Vol. 3 in eFloras.org, Missouri Botanical Garden. Accessed Nov 12, 2008.
source
Flora of North America @ eFloras.org
editor
Flora of North America Editorial Committee
project
eFloras.org
original
visit source
partner site
eFloras

Distribution

provided by EOL authors
This shrublike oak is endemic to the USA and is found in the southern Great Plains in western Oklahoma, west Texas, eastern New Mexico and two disjunctive populations in southeastern Kansas. Distantly disjunctive populations in southern Utah and northern Arizona are considered a variety of the species (Quercus havardii var. tuckeri) by some taxonomists. The range map of "Flora of North America" for this species is not complete, since i have mapped the species much further west in southern Utah, finding robust populations as far northwest as the wilderness areas of northwest Zion National Park. I have also found populations of the tuckeri variety as far east as the extreme southwestern part of Colorado, in the wilderness are to the east of Hovenweep National Monument.
license
cc-by-nc
original
visit source
partner site
EOL authors

Broad-scale Impacts of Plant Response to Fire

provided by Fire Effects Information System Plants
More info for the terms: density, fireline intensity, frequency, fuel, grassland, litter, mast, reaction intensity, shrub, shrubs

Few studies report pre- and postfire or burned and unburned Havard oak abundance. Based on the very few studies, the following
generalizations can be made: reductions in Havard oak coverage are
typical in early postfire communities, density and frequency may increase
following fire, and as time since fire increases so does sand shinnery
oak coverage. To date (2006), just 1 study reports Havard oak recovery following spring,
fall, and winter fires. Without more studies, the above
generalizations are indeed fallible.

In Kent County, Texas, Havard oak coverage decreased following a fire
on 11 March. Fire characteristics were not provided. The prefire coverage of
Havard oak was 95%; coverage the 1st and 2nd postfire years was 63.3% and
66.9%, respectively [85].

In Havard oak-dominated areas of the Black Kettle National Grassland
in Roger Mills County, Oklahoma, Havard oak stem density increased on
spring- ( April), fall- (October), and winter- (February) burned
sites, but flower and acorn production were typically lower on burned than
unburned sites. Sites had not burned for at least 10 years. Havard oak leaf litter was
approximately 3 inches (8 cm) deep before the prescribed fires. Strip headfires were set when relative humidity was below
20%, air temperature was below 84 °F (29 °C), and
surface wind speed was under 9.9 miles/hour (16 km/hr). The burning conditions and fire
behavior characteristics are summarized below for the fall, winter, and spring
fires [11,13].

  Fall Winter  Spring
Burn date 1-24 October 27 January-5 February 28 April-1 May
Air temperature (° C) 16-30 -1-16 18-29
Relative humidity (%) 21-50 24-72 20-59
Wind speed (km/hr) at 2 m above ground 6-11 5-16 3-16
1-hour live fuel (kg/m²);
 fuel moisture (%) 0.14; 66.6 0 0.013; 34.6
1-hour dead fuel (kg/m²);
 fuel moisture (%) 1.08; 17 1.3; 18.9 1.3; 14.7
10-hour dead fuel (kg/m²);
 fuel moisture (%) 0.15; 27.4 0.09; 34.3 0.08; 21.3
Flame depth (m) 1.3 2.8 2.4
Rate of spread (m/sec) 0.2 0.22 0.27
Fireline intensity (kW/m) 2,988 2,562 4,335
Heat per unit area (kJ/m²) 15,924 11,966 16,132
Fuel consumption (kg/m²) 0.94 0.70 0.95
Reaction intensity (kW/m²) 1,939 974 1,680

Fires top-killed nearly 100% of sand shinnery
oak on all burned plots. Four months following spring fires oak sprouts were 10
to 20 inches (30-40 cm) tall. Havard oak stem density was greater on
burned plots, and increases were greatest on winter- and spring-burned sites.
Havard oak coverage and height decreased following all seasons of burns,
and decreases were greatest on spring-burned sites. As time since fire
increased, however, so did Havard oak coverage. Havard oak
coverage was 55.6% on control sites and 49.5% , 45.1% , and
29.1% on winter-, fall-, and spring-burned sites in the 1st postfire growing season,
respectively. Average Havard oak coverage was 36.4%
for all seasons in the 1st postfire year and 52.0% in the 2nd postfire year [11,13].

Spring fires occurred when Havard oak
leaf expansion was approximately 50% and underground carbohydrate storage was greatest. There
was a significant (p<0.05) correlation between Havard oak postfire
growth and postfire soil phosphorus
levels. Researchers suggested that phosphorous may promote growth and/or sprouting.
Average Havard oak density and height on spring-, fall-, winter-,
and twice-burned sites are provided below for the 1st and 2nd postfire growing
seasons [11,13].

 

Stem density (stems/m²)

Canopy height (cm)


1st postfire growing season
Control 22.3 66.5
Fall 49.5 42.0
Winter 39.5 44.3
Spring 37.5 38.3
Twice-burned sites 38.7 39.6
2nd postfire growing season
Control 17.8  
Fall 42.3
46.2*
Winter 36.9
Spring 34.2

*Average height in 2nd postfire growing season for all fire seasons.

In the 1st postfire summer, no
catkins or acorns were produced on burned sites. In the 2nd postfire growing
season, however, the greatest density of acorns was produced on fall-burned
plots. The density of catkins and acorns was lowest on spring-burned plots.
Density of catkins and acorns on burned and unburned sites is summarized below
[10]. For information on the nutritional quality of buds and catkins on burned and unburned sites see Palatability/nutritional value.

  Catkin density
(no./m²) Mast density
(no. of acorns/m²)
Unburned 517.4 8.0
Fall burned 249.4 11.5
Winter burned 290.2 5.8
Spring burned 13.6 0.1

In the same area, the effect of fire on Havard oak was monitored for 2
growing seasons after 2 consecutive spring fires and for 4 growing seasons
following a single spring fire. Frequency of Havard oak was relatively the
same on unburned and burned sites evaluated 1, 2, and 4 growing seasons after
a single spring fire. The percent frequency of Havard oak was 96% on unburned plots, and 94%, 98%, and 96% on
burned sites visited in the 1st, 2nd, and 4th postfire growing seasons,
respectively. Havard oak was the dominant shrub on all plots.
Shrub coverage (dominated by Havard oak, but including sand sagebrush,
fragrant sumac (Rhus aromatica), sand plum (Prunus spp.), soapweed
yucca (Yucca glauca), netleaf hackberry (Celtis reticulata),
leadplant (Amorpha canescens), wait-a-minute (Mimosa aculeaticarpa
var. biuncifera), and/or honey mesquite) on unburned sites was 51%. Shrub coverage was significantly less (p<0.01), 38%,
in the 1st postfire growing season. On 2- and 4-year-old burned sites, shrub coverage was
56%. On twice-burned sites, coverage of shrubs was 53% in the 1st postfire
growing season and 71% in the 2nd postfire growing season. Researchers noted that 4 growing
seasons were required for litter coverage to equal that of prefire levels [37].
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Common Names

provided by Fire Effects Information System Plants
Havard oak

sand shinnery oak

shinnery oak

shin oak
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Conservation Status

provided by Fire Effects Information System Plants
Information on state-level protected status of plants in the United States is available at Plants Database.
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Description

provided by Fire Effects Information System Plants
More info for the terms: rhizome, shrub, shrubs

This description provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g. [34,49,95,97]).

Aboveground description: Havard oak is a deciduous, low-growing, thicket-forming, rhizomatous shrub. Shrubs are less than 7 feet (2 m) tall and often less than 3 feet (1 m) tall. Havard oak hybrids measure as tall as 10 feet (4 m) [34,67,70,95,97]. Havard oak is slow growing and long lived [29]. Clones may reach hundreds to thousands of years old [65]. Aboveground Havard oak stems, however, live only 11 to 15 years. Hybrid stems may live longer than 80 years [69,98]. The oldest stems of clones in Ward and Wheeler counties of Texas were 11 years of age [58]. Canopy coverage of Havard oak can be as high as 90% but averages 20% to 30% throughout its range. Biomass production averages 1,000 to 2,200 lbs/acre throughout Havard oak's range [67], although annual production as high as 4,500 lbs (2,000 kg) of air-dry forage/acre has been reported [65].

Leaves, stems, and acorns are highly variable in color, size, shape, and/or texture, and no character is readily associated with another [98]. Stems are rarely larger than 0.8 inch (2 cm) in diameter [58]. Bark becomes rough and scaly with age [49,60]. Leaves are leathery, rippled, entire, alternate, and toothed or lobed. Leaves measure 0.75 to 4 inches (2-10 cm) long and 0.75 to 1.5 inches (2-3.8 cm) wide. Number of lobes or teeth is typically 6 to 10 [34,49,70,95,97]. Male and female catkins occur on the same plant. Male catkins are 0.5 to 1.5 inches (1.5-3.8 cm) long and densely flowered. Pistillate catkins measure 0.1 to 0.3 inch (3-7 mm) long and contain 1 to 5 flowers [60,95,97]. Havard oak acorns mature in 1 year [19,34]. Acorns occur alone or in clusters of 2 or 3. Acorns are 0.5 to 1 inch (12-25 mm) long by 0.55 to 0.71 inch (14-18 mm) wide. The cups enclose 33% to 66% of the acorn [49,70,95,97].

Belowground description: The Havard oak root and rhizome system is extensive. Nellessen [60] reports that rhizomes range from 1 to 6 inches (3-15 cm) in diameter and are concentrated in the top 20 inches (60 cm) of soil, although 30-foot (9 m) penetration depths are possible. Lateral roots and woody rhizomes are widespread near the soil surface. Taproots extend 15 to 20 feet (4.6-6.1 m) deep [20,52,53]. Taproots with a diameter "equal to that of a man's thigh" are not uncommon [52]. Rhizome length is typically from 4 to 40 inches (10-100 cm) [58].

Ninety percent or more of Havard oak's biomass is under ground, and root grafting is common [66]. The mass of Havard oak roots and rhizomes is typically 10 to 16 times greater than that of the aboveground stems [69]. In a Havard oak community in Cochran and Yoakum counties of Texas, an average of 67% of the total Havard oak biomass was below ground. The root:shoot ratio was 11 for Havard oak shrubs measured in July [80].

Drought adaptations: An extensive root and rhizome network as well as physiological and morphological aboveground adaptations make Havard oak highly drought tolerant. Leaves mitigate water loss through a thick, waxy leaf epidermis [65,69]. Leaves may be dropped or leaf out postponed in adverse conditions. The extensive root system is important for water storage and utilization of available water [65].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Distribution

provided by Fire Effects Information System Plants

Havard oak is best represented in southeastern and south-central New Mexico, the panhandle of Texas, and western Oklahoma. Other populations occur in southern Utah, western Colorado, northeastern Arizona, and northwestern New Mexico [59,70,97]. Freeman [31] reports that a native Havard oak population occurs in southwestern Kansas, and a herbarium specimen from Comanche County exists [43]. For additional information on the taxonomy of Havard oak and hybrid populations, see Taxonomy.

Distribution of Havard oak. Distributions of Q. h. var. havardii and Q. h. var. tuckeri, respectively. Maps courtesy of USDA, NRCS. 2017. The PLANTS Database. National Plant Data Team, Greensboro, NC [91].

A review reports that Havard oak occupies 5 to 7 million acres (2-3 million ha) in the southern Great Plains [65]. A majority of Havard oak vegetation occurs on private land utilized for agriculture and/or livestock production. It is considered undesirable on grazing lands, and the use of chemical and mechanical control methods has been extensive (see Control), making it unlikely that the Havard oak range is expanding [56].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Fire Ecology

provided by Fire Effects Information System Plants
More info for the terms: association, density, fire exclusion, fire frequency, fire occurrence, fire regime, frequency, grassland, natural, warm-season, woodland

Fire adaptations: Havard oak sprouts from rhizomes soon after fire [3,11,53]. In Havard oak communities of northwestern Oklahoma, the density of Havard oak stems increased by approximately 15% in the 1st postfire year, and researchers described the communities as "extremely fire hardy" [54].

FIRE REGIMES: The presettlement fire frequency is estimated at less than 35 years for Havard oak communities. Since the late 1800s, however, fire frequency and fire size have decreased as a result of European settler's farming, grazing, and fire exclusion practices.

Presettlement fire frequency: While some have estimated the presettlement fire return interval for Havard oak communities, fire scar records are unavailable, so the fire regime in Havard oak vegetation is largely unknown [11]. Fire frequency estimates of neighboring southern Great Plains grasslands in areas with rolling topography range from 5 to 10 years. In the Rolling Plains and Edward Plateau regions, vegetation is often fragmented by breaks and rivers, and fires likely burned every 20 to 30 years [99].

Researchers report that Native Americans may have burned sand shinnery oak habitats in western Oklahoma as often as every year [65]. Paysen and others [64] suggest that shinnery, Texas savannah, and pinyon-juniper vegetation types experienced a mixture of understory and stand-replacing fires at intervals of less than 35 years.

Changes since settlement: Repeated fires in grasslands were typical in presettlement times; however, since the late 1800s fire occurrence has declined substantially. Together with successful fire exclusion by settlers, heavy livestock grazing in the Southwest removed much of the fire-carrying fuels and reduced the fire incidence in grasslands [30]. In presettlement times, large grassland fires were typical in drought years that followed 2 or 3 years of above average precipitation. However, since most grassland vegetation occurs in patches between agricultural and private lands today, large fires are more rare [101].

"Recurrent fires were a primary influence on stabilizing grassland or savannah vegetation composition" in the Edwards Plateau region of Texas. Most fires burned in the summer. Warm-season grasses of the Edwards Plateau have completed at least 60% of their annual growth by 1 August. Hot, dry conditions in July and August typically coincide with lightning strikes, making summer fires likely. Tall grasses were overgrazed by the late 1800s,  reducing fine fuels and fire frequency. Shortly thereafter laws were enacted that successfully excluded fire from the landscape. In the late 1990s, landowners formed the Edwards Plateau Prescribed Burning Association (EPPBA). The EPPBA has restored fire to parts of the Edwards Plateau. The EPPBA provides members with fire safety training, a pool of necessary equipment, and an educated labor force. Prescription fires set by the EPPBA burn mostly in the summer to mimic the area's natural fire regime. Since the founding of the association they have burned approximately 40,000 acres (20,000 ha) [88].

The following table provides fire return intervals for plant communities and ecosystems where Havard oak is important. Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".

Community or ecosystem Dominant species Fire return interval range (years) bluestem prairie Andropogon gerardii var. gerardii-Schizachyrium scoparium 45,64] plains grasslands Bouteloua spp. 64,100] blackbrush Coleogyne ramosissima <35 to <100  juniper-oak savanna Juniperus ashei-Quercus virginiana Ashe juniper Juniperus ashei <35  Rocky Mountain juniper Juniperus scopulorum <35 pinyon-juniper Pinus-Juniperus spp. <35 [64] mesquite Prosopis glandulosa <35 to <100 [55,64] Texas savanna Prosopis glandulosa var. glandulosa <10  oak-juniper woodland (Southwest) Quercus-Juniperus spp. <35 to <200 [64] oak savanna Quercus macrocarpa/Andropogon gerardii-Schizachyrium scoparium 2-14 [64,96] shinnery Quercus mohriana <35  little bluestem-grama prairie Schizachyrium scoparium-Bouteloua spp. <35 [64]
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Fire Management Considerations

provided by Fire Effects Information System Plants
More info for the term: fire management

The importance of Havard oak catkins and acorns in lesser prairie-chicken diets may affect the fire management of Havard oak habitats [18,76], because neither catkins nor acorns are not produced in the 1st postfire year [10,54].
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Growth Form (according to Raunkiær Life-form classification)

provided by Fire Effects Information System Plants
More info on this topic.

More info for the terms: chamaephyte, geophyte

RAUNKIAER [71] LIFE FORM:
Chamaephyte
Geophyte
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Habitat characteristics

provided by Fire Effects Information System Plants
More info for the terms: caliche, shrubs

Sandy plains, sand dunes, and sand hills of the southern Great Plains are typical Havard oak habitat [19,34,60]. In southern Utah and adjacent Arizona, Havard oak occurs on sandy sites with blackbrush (Coleogyne ramosissima), ephedra (Ephedra spp.), purple sage (Salvia dorrii), and/or pinyon-juniper (Pinus-Juniperus spp.) [97].

Elevation: Havard oak occupies relatively low elevation sites.

State/region Elevation (feet) NM 3,500-4,000 [49] TX, Trans-Pecos 2,300-3,400 [70] UT 3,690-7,000 [97]

Soils: Habitats occupied by Havard oak have sandy loam or loamy sand soils. Characteristics of these soils were summarized in a review [65]. Infiltration rates are rapid and pH is neutral or slightly basic. Soils are highly susceptible to erosion and low in organic matter, nitrogen, and phosphorus. A caliche layer more than 3 feet (1 m) below the soil surface is possible. Most sandy soils occupied by sand shinnery oak have a thin clay layer near the surface according to McIlvain [53].

Soils underneath Havard oak shrubs were sampled, analyzed, and compared with soils underneath other vegetation in the Los Medanos area of southeastern New Mexico. Soil samples were taken from 0 to 5.9 inches (0-15 cm) deep. Soil moisture, organic matter, nitrate, and phosphorus were all much lower in the Havard oak-sand sagebrush community type than in the honey mesquite-javelin bush (Condalia ericoides) community type. Average summer soil moisture beneath Havard oak ranged from 2.29% to 2.99% for a 2-year period, and organic matter averaged 0.36%. Below is a summary of the nutrient levels in the soil underneath Havard oak shrubs [81].

Nitrate Ammonium Phosphorus Calcium Magnesium

ppm

June July Aug. June July Aug. June July Aug. June July Aug. June July Aug. 0.1 0.1 0.4 0.38 0.36 0.16 0.1 0.1 0.1 18.9 35.1 21.6 1.1 1.4 1.1

Researchers found that the abundance of galls on Havard oak was greatest on sites with the highest salt levels. Shrubs were studied at the Waste Isolation Pilot Plant near Carlsbad, New Mexico. Researchers speculated that salt stress may have made Havard oak more susceptible to insect attacks [24].

Climate: Havard oak occurs in semiarid warm temperate and continental climates. Researchers summarized the climate data for 3 areas where Havard oak is common. The table below provides these data [65].

  NM, Eddy Co. OK, Roger Mills Co. TX, Yoakum Co. Mean annual precipitation (mm) 316 651 404 Mean date of last frost 31 March 2 April 13 April Mean date of first frost 7 November 28 October 1 November Mean January temperature (? C) 6.7 2.7 5.6 Mean July temperature (? C) 27.5 28.2 26.4

Droughts lasting from 2 years to decades are possible in Havard oak habitats. In the northern and southern parts of Havard oak's range, 1 to 2 years and 2 to 3 years, respectively, with precipitation levels of 75% below average are common within a 10-year period [65].

In northwestern Oklahoma, Havard oak rangelands receive an average of 22 inches (560 mm) of precipitation annually, but the range of annual precipitation is 10 to 40 inches (250-1,000 mm). Wind speeds and water evaporation rates are high in this area [54]. In Oklahoma's Black Kettle National Grasslands, where Havard oak dominates some communities, precipitation is variable, with peaks common in May and June, and in August and September [37]. In north-central Yoakum County, Texas, 80% of the annual precipitation is delivered in brief intense storms from May through October [94].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Habitat: Cover Types

provided by Fire Effects Information System Plants
More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

More info for the term: cover

SAF COVER TYPES [28]:




66 Ashe juniper-redberry (Pinchot) juniper

67 Mohrs (shin) oak

68 Mesquite

239 Pinyon-juniper

242 Mesquite
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Habitat: Ecosystem

provided by Fire Effects Information System Plants
More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

More info for the term: shrub

ECOSYSTEMS [32]:




FRES30 Desert shrub

FRES31 Shinnery

FRES32 Texas savanna

FRES33 Southwestern shrubsteppe

FRES35 Pinyon-juniper

FRES38 Plains grasslands

FRES39 Prairie

FRES40 Desert grasslands
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Habitat: Plant Associations

provided by Fire Effects Information System Plants
More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: woodland

KUCHLER [46] PLANT ASSOCIATIONS:




K023 Juniper-pinyon woodland

K039 Blackbrush

K057 Galleta-threeawn shrubsteppe

K058 Grama-tobosa shrubsteppe

K060 Mesquite savanna

K065 Grama-buffalo grass

K069 Bluestem-grama prairie

K070 Sandsage-bluestem prairie

K071 Shinnery

K074 Bluestem prairie

K085 Mesquite-buffalo grass

K086 Juniper-oak savanna

K087 Mesquite-oak savanna
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Habitat: Rangeland Cover Types

provided by Fire Effects Information System Plants
More info on this topic.

This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):

More info for the terms: cover, woodland

SRM (RANGELAND) COVER TYPES [83]:




412 Juniper-pinyon woodland

413 Gambel oak

504 Juniper-pinyon pine woodland

701 Alkali sacaton-tobosagrass

702 Black grama-alkali sacaton

708 Bluestem-dropseed

710 Bluestem prairie

712 Galleta-alkali sacaton

717 Little bluestem-Indiangrass-Texas wintergrass

718 Mesquite-grama

720 Sand bluestem-little bluestem (dunes)

721 Sand bluestem-little bluestem (plains)

722 Sand sagebrush-mixed prairie

727 Mesquite-buffalo grass

729 Mesquite

730 Sand shinnery oak

733 Juniper-oak
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Immediate Effect of Fire

provided by Fire Effects Information System Plants
Havard oak is top-killed by fire. Fall, winter, and spring prescription fires top-killed nearly 100% of Havard oak in western Oklahoma [11].
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Importance to Livestock and Wildlife

provided by Fire Effects Information System Plants
More info for the terms: avoidance, cover, density, frequency, litter, relative density, shrub, shrubs

Diverse wildlife species utilize Havard oak habitats for cover and food. Collared peccaries, lesser prairie-chickens, northern bobwhites, and other wildlife species eat Havard oak acorns [19,65,70,95]. Deer, pronghorn, and southern plains woodrats browse Havard oak [60]. In a review, Peterson and Boyd [65] report that black-tailed jackrabbits, desert cottontails, eastern cottontails, wild turkeys, western box turtles, a diversity of arthropods, approximately 25 snake species, and approximately 10 lizard species utilize Havard oak habitats. Scaled quail and northern bobwhites use Havard oak habitats extensively, and Havard oak habitats are considered "the principal home for white-tailed deer in the southern Great Plains" [65].

Livestock: Havard oak is poisonous to horses, domestic sheep, goats, and cattle. Tannic acid is considered the poisoning agent, but other compounds may contribute [1]. Cattle consuming high levels of sand shinnery oak develop rumen ulceration and eventually suffer liver and kidney failure. Domestic goats tolerate a diet with more Havard oak than cows; however, a diet of just Havard oak kills goats [69]. Livestock poisoning is most common in the spring when Havard oak buds and immature leaves are consumed readily and other food is scarce. Without treatment livestock death rates can be as high as 85%. Removing livestock from Havard oak-dominated sites or providing additional feed may reduce the chance of poisoning [1]. For additional information on tips for avoidance and symptoms of poisoning, see James and others [41].

When oak species make up greater than 50% of the forage, livestock poisoning may occur. If diets exceed 75% Havard oak, animals may die [36]. The 50% and 75% consumption estimates, however, are based on consumption of plants with 2% to 6% tannin concentrations. Early in the spring tannin levels can be as high as 18% to 20%, meaning that consumption levels much lower than 50% could cause illness or death [92]. For additional information on stocking rates and rotational grazing patterns that may decrease the chances of poisoning in Havard oak habitats, see Peterson and Boyd [65].

Cattle may be poisoned by consuming Havard oak. Havard oak is most toxic in the spring growing season [56] and if consumed without other forage [57]. Poisoned cattle initially excrete dark, dry feces with mucus and blood and have a decreased appetite. Without supplemental feeding or treatment, cattle have bloody diarrhea, urinate frequently, and drink water excessively. A rough coat, dry muzzle, and reddish urine are typical in the late stages of poisoning. Nursing calves may be the most susceptible. Tannins consumed by the mother concentrate in the milk. Havard oak poisoning is considered a "symptom of overstocking and poor range condition" [92].

Cattle browse high levels of Havard oak when other forage is unavailable, during drought conditions, or in heavily grazed areas. Researchers suggest that animals should be kept off oak-dominated ranges until foliage is at least 30 days old [36]. In sandhills communities in the Texas panhandle, researchers found that Havard oak made up 15.3% of spring, 16.2% of summer, and 23.8% of fall cattle diets. Diet was determined through fecal analysis and observations. Havard oak abundance rather than preference was responsible for cattle consumption levels [77].

Domestic goats: Angora and Spanish goats browse Havard oak extensively without suffering the poisoning described above. Havard oak made up 31.7%, 45.0%, and 55.1% of Angora and Spanish goat diets in June, July, and August, respectively. Goats were in north-central Yoakum County, Texas, where Havard oak made up 80% of the available forage. Tannin content did not change much from June to September and averaged 36.7 mg/g in leaves and 37.6 mg/g in stems [93,94]. A review reports that domestic goats that continually browse Havard oak lose weight [60].

Sheep: In the Palo Duri Canyon of Texas, fecal samples were collected for approximately 2 years. Researchers found that Havard oak made up 31.0% of the relative density of Barbary sheep diets. Diets of mule deer and Barbary sheep in the area had a high degree of overlap [44]. Peterson and Boyd [65] speculate that this study may have mistaken Havard oak for Mohr oak.

Native animals: Native ungulates, small mammals, birds, insects, and lizards utilize Havard oak habitats and/or consume Havard oak.

Pronghorn: Spring, summer, fall, and winter pronghorn diets were 7.8%, 20.8%, 21.4%, and 3.6% Havard oak in sandhill communities of the Texas panhandle. Pronghorn diets had a high degree of overlap with cattle in the same area in the summer and fall months [77].

Deer: Havard oak is important deer browse. In the Palo Duri Canyon of Texas, fecal samples were collected for approximately 2 years. Researchers found that Havard oak made up 37.2% of the relative density of mule deer diets. Armstrong [3] reports that the occurrence of heavily browsed plants in July and August indicates overutilized white-tailed deer range.

Lesser prairie-chickens: Havard oak is important in lesser prairie-chicken habitats and diets. Lesser prairie-chickens are candidates for listing as threatened or endangered throughout their range. For more on the lesser prairie-chicken and its current status, see the U.S. Fish and Wildlife Service website.

Havard oak was a major component of the lesser prairie-chicken's spring and summer diets in the Mescalero Sands of eastern New Mexico. Based on a 2-year study, lesser prairie chicken diets were 15.2% Havard oak acorns, 31.8% catkins, and 2.1% leaves in the spring (March-May) and 21.2% acorns and 0.2% leaves in the summer (Jan-April). In the study area, Havard oak made up 29.1% to 48.8% of the vegetation composition [18]. In Chaves County, New Mexico, Havard oak acorns comprised 17% to 61% of fall diets and 69% of winter diets. Havard oak insect galls made up 5% of winter and 14% of fall diets based on crops collected over a 2-year period. Researchers indicated that Havard oak is the most heavily utilized year-round food source for lesser prairie-chickens [74].

In Cochran County, Texas, 90 lesser prairie-chicken crops were collected and analyzed over a period of 3 years. The frequency of Havard oak leaves, acorns, and galls were 8.0%, 15.9%, and 39.7%, respectively. Percentage of Havard oak leaves, acorns, and galls by volume were 0.3%, 5.0%, and 15.3%, respectively [15]. The percentage of lesser prairie-chicken body fat was significantly (p<0.05) greater on untreated than on herbicide (tebuthiuron)-treated sites in Cochran and Yoakum counties of Texas and Lea and Roosevelt counties of New Mexico. Treated sites had significantly less (p<0.01) Havard oak based on basal composition percentages than untreated sites [61].

Lesser prairie-chicken populations in Havard oak communities in New Mexico and Oklahoma's Sutton Avian Research Centers utilized sites with increased coverage and density of shrubs. Survivorship of the lesser prairie-chicken was greater when sites had over 20% shrub cover than when sites had less shrub cover. Havard oak dominated the shrub layer in New Mexico, but its importance decreased in Oklahoma [63]. In Cochran and Yoakum counties of Texas, fewer lesser prairie-chicken nests were located in herbicide-treated than in untreated Havard oak sites. Of 10 nesting females, 8 nested in untreated sites, and 2 nested in treated sites. Researchers indicated that Havard oak stems and foliage provided important vertical screening cover for nests [38]. However, in high plains bluestem vegetation in southeastern New Mexico nests were more successful when tall grasses provided the principal nest cover. Of the 4 nests with Havard oak as the principal cover, none were successful (hatched at least 1 young) [75].

Other birds: Hawks, mourning doves, and scaled quail occupy Havard oak habitats. Harris' and Swainson's hawks utilize Havard oak shrublands of southeastern New Mexico [4,5]. Mourning doves occupy Havard oak habitats in southeastern New Mexico [7]. Havard oak habitats in northwestern Oklahoma supported 0.035 mourning dove breeding pairs, and ground nesting success was 33% based on data collected for a single nesting season [25]. In southeastern New Mexico, Havard oak was 2.6% of the average volume of foods in 50 scaled quail crops collected in 1971. Crops collected in 1970, 1972, and 1973 did not contain Havard oak. Havard oak was abundant in part of the study area, but abundance values were not reported [17]. The crops of northern bobwhites harvested from Havard oak habitats in northwestern Oklahoma contained 10.9% Havard oak by volume [35].

Small mammals: Havard oak communities provide important habitat and cover and an occasional food source for a variety of small mammals. The following rodents were trapped in Havard oak-dominated sites of Yoakum County, Texas: Ord's kangaroo rat, plains pocket, hispid pocket mouse, deer mouse, western harvest mouse, plains harvest mouse, northern grasshopper mouse, hispid cotton rat, southern plains woodrat, house mouse, and spotted ground squirrel [14]. Based on stomach content analyses, a single Ord's kangaroo rat consumed Havard oak. Havard oak was not recovered from northern grasshopper mouse, southern plains woodrat, or spotted ground squirrel stomachs. All trappings occurred in Havard oak-mesquite grasslands of southeastern New Mexico from March 1978 to December 1979 [8]. Ringtails are also common in Havard oak communities [86].

Herptiles: Snell (personal communication in [79]) indicates that dune lizard populations declined by 70% to 94% in New Mexico when Havard oak was removed.

Insects: Weevils, caterpillars, and grasshoppers utilize Havard oak as a food source or as habitat. Likely the diversity of insects utilizing Havard oak is greater than current research suggests. A puss caterpillar of Oklahoma feeds extensively on Havard oak. Tannins of the leaves are used in their venomous hairs or spines [47]. Havard oak is a primary component of spotted bird grasshopper diets in New Mexico. Levels of grasshopper herbivory were greatest on plots where Havard oak had the fewest galls [24]. Boll weevils overwinter in Havard oak litter, which is considered prime overwintering habitat [85].

Palatability/nutritional value: In western Oklahoma, researchers evaluated the nutritional quality of Havard oak leaf buds and catkins on unburned, ungrazed, grazed, and fall-, winter-, and spring-burned sites. Values were reported for the 2nd postfire year, and ungrazed sites were free of cattle for a single growing season. Nutritional quality of buds and catkins on burned, unburned, grazed, and ungrazed sites were similar. The percentage of phenolics was greater on burned and grazed than unburned and ungrazed sites. Comparisons of catkin nutrition were not made on grazed and ungrazed sites because catkins were too few on grazed sites. The nutritional quality of buds and catkins on burned and unburned sites is summarized below [12].

  Crude protein (%) Phenolics (%) Acid-detergent fiber (%) Ash (%) Buds Unburned 22.4 16.1 23.5 4.6 Fall burned 23.2 18.1 20.9 4.3 Winter burned 22.9 15.3 22.5 4.1 Spring burned 24.1 18.6 22.6 4.2 Catkins Unburned 20.7 12.2 18.2 4.4 Fall burned 21.1 15.2 18.9 4.3 Winter burned 21.5 15.0 18.2 4.2 Spring burned 21.7 15.1 21.2 3.9

Cover value: The importance of Havard oak as cover and in the habitats of wildlife species has been integrated into the above sections. For additional information on the importance of Havard oak in wildlife habitats, see the species group of interest within Importance to Livestock and Wildlife.

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Key Plant Community Associations

provided by Fire Effects Information System Plants
More info for the terms: alliance, forb, series, shrub, shrubland

Havard oak is a dominant species in the following vegetation types:



New Mexico:

  • Havard oak/little bluestem (Schizachyrium scoparium)-silver bluestem
    (Bothriochloa saccharoides) in east-central and southeast


  • Havard oak-sand sagebrush (Artemisia filifolia)-plains yucca (Yucca campestris)/sand
    bluestem (Andropogon hallii)-purple threeawn (Aristida purpurea) in east-central
    and southeast


  • Havard oak-fourwing saltbrush (Atriplex canescens)/alkali
    sacaton (Sporobolus airoides)-annual buckwheat (Eriogonum annuum)
    in east-central and southeast


  • Havard oak-sand sagebrush/mixed grass and
    forb in east-central and southeast [23]


  • Havard oak/little bluestem shrubland [78]


  • active duneland community


  • honeymesquite (Prosopis glandulosa)/Havard oak/hairy grama (Bouteloua hirsuta)-purple
    threeawn


  • honeymesquite/Havard oak/purple threeawn-sand dropseed
    (Sporobolus cryptandrus)


  • honey mesquite/Havard oak/hooded windmill grass (Chloris cucullata)-large-spike
    bristlegrass (Setaria macrostachya)


  • honey mesquite/javelin bush (Condalia ericoides)-Havard oak/purple threeawn-sand dropseed


  • Havard oak/snakeweed (Gutierrezia spp.)/purple threeawn-little bluestem


  • Havard oak/little bluestem-sand bluestem


  • Havard oak/little bluestem-Havard's panicgrass(Panicum havardii)


  • Havard oak/purple threeawn-fall witchgrass (Digitaria cognata)


  • Havard oak/purple threeawn-sand dropseed


  • Havard oak/purple threeawn-sand bluestem [48]


  • Havard oak shrub alliance in Chihuahuan Desert [72]



Oklahoma:


  • oak savannah vegetation [73]


  • Havard oak shrub alliance and Havard oak/sand dropseed-little bluestem [40]


  • Havard oak/Mohr oak-dwarf chinkapin oak (Quercus prinoides)/little
    bluestem shrubland [78]



Texas:


  • Havard oak savannah in parts of Edwards Plateau [2]


  • Havard oak-tall grass communities in the Rolling Plains, High Plains,
    and sand hills of the Trans-Pecos region [22]


  • Havard oak/little bluestem shrubland [78]


  • Havard oak-tallgrass series in the panhandle, High Plains, and northeastern
    Trans-Pecos regions [89]


  • Havard oak/Havard's panicgrass-giant sandreed (Calamovilfa
    gigantea) on actively moving sand dunes in Winkler and Andrews counties


  • Havard oak/Havard's panicgrass-giant dropseed (Sporobolus giganteus)


  • Havard oak/giant dropseed-Havard's panicgrass on more stable sand dunes


  • Havard oak/sand dropseed-giant dropseed


  • Havard oak/giant dropseed (Sullivan 1980, cited in [65])

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Life Form

provided by Fire Effects Information System Plants
More info for the term: shrub

Shrub
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Management considerations

provided by Fire Effects Information System Plants
More info for the terms: litter, seed

Wildlife-livestock management:
Havard oak habitats are likely candidates for wildlife-livestock management
conflicts. Boll weevil pests overwinter in Havard oak litter [85], and
cattle may be poisoned by Havard oak [92]. Many have attempted to control
Havard oak to lessen the success
of boll weevils, increase available livestock forage, and reduce livestock
poisoning risks [27,39,85]. However, sand shinnery
oak provides important habitat and food for a variety of wildlife and plant species
[65], some of which are endangered as of this writing (2006). The Texas poppymallow (Callirhoe
scabriuscula) and aplomado falcon occur in sand shinnery
oak habitats and are federally endangered. The Texas horned lizard that occurs in
Havard oak habitats is threatened in Texas [21], and the lesser prairie-chicken
that is highly dependent on sand shinnery
oak is a candidate for listing. See U.S. Fish and Wildlife Service, NatureServe,
and/or Texas Parks and Wildlife
databases for more information on the current status of these species.

Competition/allelopathy:
Studies found that extracts of sand shinnery
oak leaves significantly (p<0.05) suppressed the initial root elongation of 'Ermelo'
weeping lovegrass (Eragrostis curvula) seeds. Germination percentage and
shoot elongation of seeds kept moist with Havard oak leaf extracts were
not reduced. Weeping lovegrass seed produced roots that were 1.2 inches (31 mm) in
distilled water, but roots were 0.08 inch (2 mm) long in Havard oak extracts [50].



Control:
The following references include information on a variety of control methods and may prove
useful in the quest for additional information [27,39,42,65,85]. Herbel and others
[39] provide information on the timing of
Havard oak control. They do not recommend complete eradication of sand shinnery
oak and indicate that forage production is typically greater if some sand shinnery
oak remains in the community.
Peterson and Boyd [65] present information on stocking rates
and rotational grazing patterns that may reduce the incidence of sand shinnery
oak poisoning of cattle.
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Other uses and values

provided by Fire Effects Information System Plants
More info for the term: presence

Acorns were likely consumed by native people in the southern Plains. Presence of Havard oak may have also indicated productive hunting areas.
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Phenology

provided by Fire Effects Information System Plants
More info on this topic.

More info for the term: shrubs

Havard oak buds break in mid-March, and leaves and flowers appear in April and May [49,92]. Flowers appear before the leaves [52]. Acorns are mature by mid-July or September [60]. Shrubs are typically physiologically active until October or late November [92].
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Plant Response to Fire

provided by Fire Effects Information System Plants
More info for the terms: density, shrubs, top-kill

Havard oak sprouts vigorously from rhizomes following fire [3,52,53]. Postfire sprouting is quick. In a review, Peterson and Boyd [65] report that new aboveground stem growth is visible within 1 to 2 months after top-kill or aboveground damage. Immediately following fire, sand shinnery oak is reduced in size, but burned stands are normally "thicker" than unburned stands due to postfire sprouting [53]. Shrubs can reach 3 to 4 feet (0.9-1 m) tall by the 2nd or 3rd postfire year [52]. In northwestern Oklahoma, Havard oak stem density increased by approximately 15% in the 1st postfire year, and researchers described the communities as "extremely fire hardy" [54].
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Post-fire Regeneration

provided by Fire Effects Information System Plants
More info for the terms: rhizome, shrub

POSTFIRE REGENERATION STRATEGY [87]:
Rhizomatous shrub, rhizome in soil
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Regeneration Processes

provided by Fire Effects Information System Plants
More info for the terms: avoidance, cover, monoecious, radicle, rhizome, seed, shrub, shrubs

Rhizome extension is important in the horizontal spread of Havard oak, but sexual regeneration is episodically important [51]. Muller [58] suggests that although abundant seed is produced, seedling establishment is rare and often restricted to open or disturbed sites. In a review, inadequate moisture conditions for seed germination and seedling establishment are proposed as reasons for poor seedling establishment rather than lack of seed production [65].

Work in western Texas and western Oklahoma suggests that sexual regeneration is rare. Researchers conducting studies in the Llano Estacado area of western Texas found no seedlings in a year-long study of Havard oak communities, and later in the same area no viable acorns were found [20]. In observational studies of Havard oak communities in western Oklahoma, Wiedman [98] encountered no seedlings.

Pollination: Oak (Quercus spp.) flowers are wind pollinated. Catkin morphology aids in successful wind dispersal of pollen [82].

Breeding system: Havard oak is a monoecious shrub [34], and the existence of hybrids suggests that outcrossing is common. Self compatibility of flowers was not described in current (up to 2006) literature.

Seed production: On average acorn crops are produced in 3 of 10 years [69]. Nellessen [60] reports that although acorn crops are produced in 3 of every 10 years per clone, acorns are likely found within a community each year. Hanson [35] reported that Havard oak produced large quantities of large-sized acorns during his study of northern bobwhites in 1951 and 1952 in northwestern Oklahoma.

Peterson and Boyd [65] report that "heavy local crops occurred somewhere every year," but within a community, acorn crops were not produced more than 2 years in 5 from 1977 to 1997 in New Mexico. If shrubs experience a freeze after flowering, no acorns are produced [69].

Seed dispersal: Small mammals and birds may aid in the dispersal of oak acorns by abandoning caches. American and European jays often cache acorns a few meters apart in open environments and cover them with debris or soil [26].

Seed banking: Havard oak acorns rarely survive after early January because of heavy predation by insects and other animals [35], suggesting that a seed bank is unlikely. Acorns of the white oak group have little or no dormancy and are capable of germination immediately after falling. It is likely that acorns that survived predation would not persist in the seed bank [9].

Germination: Moisture at the time of seed fall and successful avoidance of predators are necessary for germination of Havard oak acorns [60,69]. Seed viability is lost when acorn moisture levels drop below 30% to 50% [60]. Late July and/or early August moisture is required for successful Havard oak germination [69].

Germinating acorns 1st produce root tissue. The initial root may be 12 inches (30 cm) long before the 1st leaves emerge [69].

Seedling establishment/growth: Havard oak growth rates above and below ground are often greater with increased moisture. Monitoring the root growth of acorns with approximately 0.8 inch (2 cm) radicle emergence using glass-front growth chambers revealed that growth is more dependent on soil moisture than soil temperature. Just 2 of 15 seedlings survived cool-dry treatments, and root extension stopped after 2 weeks in dry-warm treatments. Regardless of temperature, moist and wet treatments produced root extension rates of 0.080 to 0.094 inch (0.20 to 0.24 cm)/day throughout the 52-day study. Researchers suggest that Havard oak regeneration from acorns is likely restricted to long wet periods [84].

Growth rates of Havard oak in Ellis County, Oklahoma were 1.1 mm/year and in hybrid populations in Harmon County were 0.2 inch (5.2 mm)/year [98]. Havard oak ? post oak hybrids in Texas grew at an extremely slow rate. Tree-shrubs over 50 years old were developing a "heart rot like condition," and ring growth was less than 0.2 mm/year. Two growth rings revealed more rapid growth rates that likely coincided with above-average precipitation levels [68].

Asexual regeneration: Havard oak spreads by rhizome growth and sprouts from rhizomes following aboveground stem damage. Lateral woody rhizomes are capable of sprouting along their entire length [52,53]; however, spread by rhizomes is slow. Studies in Oklahoma showed a spread of just 30 feet (9 m) in 50 years [69]. Sprouting after destruction of aboveground stems is quick. New stem growth is typically visible within 1 to 2 months after removal of or damage to aboveground stems [65]. Shoot regeneration rates of 10 to 20 inches (30-60 cm) per year were reported following aboveground kill or damage [60].

Clone size can be very large. In Yoakum County, Texas, 2 acres (1 ha) contained an average of 15 distinct Havard oak clones. Researchers speculated that vegetative reproduction was important in horizontal spread but was not a substitute for sexual reproduction, which may occur only episodically. Clonal shape was variable. Some were densely clumped and circular, others were long and narrow or meandering, and others were convoluted and fragmented by other clones. Clone size ranged from ~100 to 7,000 m? [51]. Clone size in Ward and Wheeler counties of Texas ranged from 10 to 49 feet (3-15 m) in diameter [58]. Havard oak ? post oak hybrid clones in Texas were a product of extensive asexual regeneration. Eighty nine tree-shrubs were determined to be a single clone. Havard oak ? post oak and Havard oak seedlings were rare in the field [68].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Regional Distribution in the Western United States

provided by Fire Effects Information System Plants
More info on this topic.

This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

BLM PHYSIOGRAPHIC REGIONS [6]:




12 Colorado Plateau

13 Rocky Mountain Piedmont

14 Great Plains
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

States or Provinces

provided by Fire Effects Information System Plants
(key to state/province abbreviations)
UNITED STATES AZ KS NM OK TX UT
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Successional Status

provided by Fire Effects Information System Plants
More info on this topic.

More info for the terms: rhizome, shrub

In a review, researchers indicate that Havard oak is tolerant of disturbance, occurs as a very old shrub in late seral communities, but colonizes open sites at a very slow rate. Following top-killing disturbances, Havard oak regeneration is typically quick. In some Havard oak communities, root and rhizome systems are estimated to be hundreds to thousands of years old.

Havard oak's response to grazing pressure is mixed. Some have labeled Havard oak as an "increaser" on grazed sites, while others have reported no change or a decrease in Havard oak on grazed sites [65].

Havard oak does not readily colonize open sites. If removed from a site, reinvasion is slow. Old field sites in Oklahoma, abandoned in the early 1900s, were dominated by grasses 50 years later, although Havard oak communities surrounded the sites [53].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Taxonomy

provided by Fire Effects Information System Plants
More info for the terms: introgression, shrub

The scientific name of Havard oak is Quercus havardii Rydb. (Fagaceae)
[33,34,43,49,97]. Havard oak belongs to the white oak group (Leucobalanus) [19]. Some
[43,91,97] recognize 2 varieties, Q. h. Rydb. var.
havardii and Q. h. Rydb. var. tuckeri Welsh,
but other taxonomic authorities do not [33].

Havard oak populations in the Navajo Basin of Utah and Arizona are
considered pure Havard oak (Q. havardii var. tuckeri)
by some [97], but introgression with
Gambel oak (Q. gambelii) and perhaps shrub live oak (Q. turbinella) make taxonomic
identification of Utah and adjacent Arizona Havard oak populations difficult [90].


Havard oak also hybridizes with Mohr oak (Q. mohriana) and post oak (Q. stellata)
[59,70,95]. Post oak × Havard oak hybrids are likely a result of post oak's historic range, which
extended more westerly than it does today. Mohr
oak × Havard oak hybrids are restricted to
habitats intermediate to those occupied by the 2 species. Mohr oak
inhabits limestone soils, and Havard oak occurs on deep sand soils [59].

license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Value for rehabilitation of disturbed sites

provided by Fire Effects Information System Plants
More info for the terms: restoration, rhizome

Havard oak's extensive root and rhizome system is valuable as a soil stabilizer on sandy sites [60]. However, ease of establishment of this species in restoration or revegetation projects is unknown.
license
cc-publicdomain
bibliographic citation
Gucker, Corey L. 2006. Quercus havardii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/quehar/all.html

Quercus havardii ( Azerbaijani )

provided by wikipedia AZ


Quercus havardii (lat. Quercus havardii) - fıstıqkimilər fəsiləsinin palıd cinsinə aid bitki növü.

Mənbə

Bu şablona bax Palıd cinsinə aid növlər Q. griseaQ. oblongifoliaQ. acerifoliaQ. acutaQ. acutissimaQ. afaresQ. agrifoliaQ. albaQ. albocintaQ. alienaQ. alnifoliaQ. arizonicaQ. arkansanaQ. aucheriQ. austrinaQ. basaseachicensisQ. benthamiiQ. berberidifoliaQ. bicolorQ. boyntoniiQ. brandegeeiQ. brenesiiQ. brevilobaQ. buckleyiQ. bumelioidesQ. calliprinosQ. canariensisQ. castaneifoliaQ. cedrosensisQ. cerrioidesQ. cerrisQ. chapmaniiQ. chrysolepisQ. coahuilensisQ. cocciferaQ. coccineaQ. convallataQ. conzattiiQ. copeyensisQ. cornelius-mulleriQ. corrugataQ. costaricensisQ. cubanaQ. deliquescensQ. dentataQ. depressaQ. depressipesQ. deviaQ. diversifoliaQ. douglasiiQ. dumosaQ. durataQ. ellipsoidalisQ. emoryiQ. engelmanniiQ. excelsaQ. fagineaQ. falcataQ. flagelliferaQ. frainettoQ. fulvaQ. fusiformisQ. galeanensisQ. gambeliiQ. garryanaQ. georgianaQ. germanaQ. glaucaQ. glaucoidesQ. graciliformisQ. gravesiiQ. gulielmitreleaseiQ. havardiiQ. hemisphaericaQ. hintoniiQ. hintoniorumQ. humboldtiiQ. hypoxanthaQ. ibericaQ. ilexQ. ilicifoliaQ. imbricariaQ. invaginataQ. john-tuckeriQ. kelloggiiQ. laceyiQ. laevisQ. lamellosaQ. laurifoliaQ. libaniQ. liebmanniiQ. lobataQ. lusitanicaQ. lyrataQ. macdonaldiiQ. macdougalliiQ. macrantheraQ. macrocarpaQ. macrolepisQ. marilandicaQ. martineziiQ. michauxiiQ. miquihuanensisQ. mohrianaQ. mongolicaQ. muehlenbergiiQ. myrsinifoliaQ. nigraQ. oglethorpensisQ. oleoidesQ. pacificaQ. pagodaQ. palmeriQ. palustrisQ. peninsularisQ. perpallidaQ. petraeaQ. phellosQ. planipoculaQ. polymorphaQ. ponticaQ. praecoQ. praineanaQ. prinoidesQ. prinusQ. pubescensQ. pungensQ. purulhanaQ. rapurahuensisQ. roburQ. robustaQ. rubraQ. rugosaQ. rysophyllaQ. sadlerianaQ. sebiferaQ. shumardiiQ. skinneriQ. skutchiiQ. stellataQ. suberQ. subspathulataQ. tardifoliaQ. texanaQ. tomentellaQ. tonduziiQ. toumeyiQ. trojanaQ. turbinellaQ. undataQ. uxorisQ. vacciniifoliaQ. variabilisQ. velutinaQ. vincentensisQ. wislizeniQ. xalapensisQ. zempoaltepecanaQ. × alvordiana Inula britannica.jpeg İkiləpəlilər ilə əlaqədar bu məqalə qaralama halındadır. Məqaləni redaktə edərək Vikipediyanı zənginləşdirin.
license
cc-by-sa-3.0
copyright
Vikipediya müəllifləri və redaktorları
original
visit source
partner site
wikipedia AZ

Quercus havardii: Brief Summary ( Azerbaijani )

provided by wikipedia AZ


Quercus havardii (lat. Quercus havardii) - fıstıqkimilər fəsiləsinin palıd cinsinə aid bitki növü.

license
cc-by-sa-3.0
copyright
Vikipediya müəllifləri və redaktorları
original
visit source
partner site
wikipedia AZ

Quercus havardii ( Catalan; Valencian )

provided by wikipedia CA

Quercus havardii és una espècie de roure caducifoli, de creixement baix, arbustiu, que ocupa pel voltant de 2 a 3 milions d'hectàrees al sud de les Grans planes d'Amèrica del Nord.[1] Els clons poden arribar a centenars de milers d'anys d'antiguitat, encara que les tiges solen viure sobre el sòl només 11 o 15 anys. Els troncs d'aquest tipus de roure són generalment 1-2 m d'alçada i codominant la comunitat vegetal de gramínies mitjanes i altes, que solen ser més altes que els roures.

L'honor de portar l'epítet específic va ser pel cirurgià i botànic de l'Exèrcit dels EUA el Sr. Valery Havard, que va contribuir molt al coneixement de les plantes del sud-oest.[2]

Descripció

És un arbust de menys de 2 m, o ocasionalment un petit arbre. Q. havardii forma grans matolls clonals mitjançant l'extensió de rizomes, on es troba generalment pel terra sorrenc.[3] Els rizomes poden variar de 3-15 cm de diàmetre i es concentren en 60 cm superiors del sòl, encara que també s'ha informat d'una penetració de 9 m. Les arrels laterals i rizomes llenyosos s'han generalitzat a prop de la superfície del sòl. El 90% o més de la biomassa aquest tipus de roure està sota terra, i és comú l'arrel d'empelt fortuïta. Aquestes tiges subterrànies normalment s'estenen per formar les plantes de 3 i 15 m de diàmetre o més. S'ha informat de clons individuals que cobreixen fins a 81 hectàrees i poden arribar a edats de més de 13.000 anys.[1] L'escorça de les tiges més grans són de color gris i escamoses. Les branques són de color marró o grisenc, 1-2,5 mm de diàmetre, glabres o densament cobertes de pèls curts de color grisenc o groguenc, que es perden amb l'edat. Els brots són de color vermellós marronós fosc, una mica esfèric, d'uns 2 mm de llarg, pubescent i baixa densitat. Les fulles són coriàcies, molt variables de gris a verd oliva, té una superfície superior brillant, i són blanquinoses i densament velloses per sota. Les fulles són alternatives, senzilles, variable en la forma (rectangular, oval o el·líptica), amb marges superficialment ondulats o lobulades. La longitud és de 2 a 8 cm i l'amplada de 2 a 4 cm.[2] Aquest tipus de roure és monoic amb flors de tots dos sexes estan separats a la mateixa planta.[4] Els aments mascles estan densament florits, 1,5-3,8 cm de llarg, i penjat cap avall. Els aments femelles són 3-7 mm de llarg, contenen d'1 a 5 flors, i en general, els brots joves són axil·lars. Aquests roures són pol·linitzats pel vent, i la floració es produeix a la primavera. Les glans es desenvolupen en 1 any, i maduren a la tardor. Les glans surten soles o en grups de 2 o 3, i són 12-25 mm de llarg per 14-18 mm d'ample. Una tassa escamosa cobreix aproximadament 1/3 a 1/2 de la nou. De mitjana, els cultius de gla es produeixen en 3 de cada 10 anys.[3]

Taxonomia

Les poblacions del Quercus havardii a Utah i Arizona es consideren una varietat de Quercus havardii var. tuckeri per algun taxònom. Tanmateix, la introgressió del Quercus havardii amb el Quercus gambelii) i potser el Quercus turbinella, fa difícil la identificació taxonòmica d'aquestes poblacions.[3]

Quercus havardii s'hibrida amb Quercus mohriana i amb Quercus stellata. Els híbrids de Quercus stellata x Quercus havardii és probable que siguin el resultat de la sèrie històrica després de roure, que s'estenia més cap a l'oest que actualment. Els híbrids de Quercus mohriana x Quercus havardii estan restringits als hàbitats intermedis que ocupen les dues espècies. El Quercus mohriana habita en els sòls de pedra calcària, i el Quercus havardii es produeix en sòls sorrencs profunds.

Àrea de distribució natural

Quercus havardii és natiu a l'oest d'Oklahoma, a l'oest de Texas, a l'est de Nou Mèxic, i dues poblacions aïllades al sud-oest de Kansas.[5] Una varietat també creix al nord-est d'Arizona i el sud-est de Utah.[6] Planes arenoses, dunes de sorra i turons de sorra de les Grans planes del sud són l'hàbitat típic.

Gestió

La majoria de Quercus havardii creixen en terres de propietat privada dedicada a l'agricultura i/o ramaderia. Es considera indesitjable en les terres de pasturatge, ja que competeix amb el millor farratge per al bestiar i els seus brots i les fulles són tòxiques per al bestiar durant diverses setmanes a la primavera. A més, quan el cotó es cultiva a prop d'aquest tipus de roure, els corcs del cotó passen l'hivern en la fullaraca del roure i infesten els camps de cotó pels voltants de la primavera. Així, el màxim esforç d'investigació i altres activitats humanes sobre Quercus havardii s'han dedicat a la seva erradicació.

L'ús de mètodes químics i mecànics de control ha estat àmplia, de manera que és probable que la distribució de Quercus havardii està disminuint. La majoria de les autoritats no en recomana l'erradicació completa d'aquest tipus de roure, el que indica que la producció de farratge és típicament més gran si algun Quercus havardii roman en la comunitat. Les densitats de sembra i patrons rotacional que existeixen redueixen la incidència d'enverinament de bestiar a causa d'aquest tipus de roure. El control excessiu de Quercus havardii és polèmic, ja que pot obrir els sòls sorrencs a l'erosió del vent i poden entrar en conflicte amb la qualitat de l'hàbitat de la vida silvestre.[1]

Els brots dels rizomes de Quercus havardii són prolífics, poc després d'un incendi. Els investigadors van descriure les comunitats com "extremadament resistent al foc".[3]

Usos

Aquest tipus de roure creix en un ambient hostil, funciona com un estabilitzador de dunes, la protecció dels sòls sorrencs de l'erosió del vent. També proporciona cobertura diversa espècies de vida silvestre i els aliments. Els pècaris de collar, els galls de les praderies petits, els colins de Virgínia, i moltes altres espècies de vida silvestre mengen glans de Quercus havardii. Els cérvols de Virgínia, els antílops americans, i el gènere de ratolins Neotoma són assidus en aquest tipus de roure. Els hàbitats de Quercus havardii són utilitzats per les llebres californianes, pels conills del desert, conills de Florida, galls dindis salvatges, Terrapene ornata (un tipus de tortuga), una diversitat d'artròpodes, aproximadament 25 espècies de serps i aproximadament 10 espècies de lacertilis (un tipus de rèptil), incloent-hi el llangardaix de dunes en perill (Sceloporus arenicolus).[1] Moltes espècies de caça es basen també en aquest tipus de roure. La guatlla escamosa i les guatlles del nord utilitzen àmpliament els hàbitats de Quercus havardii, i els hàbitats d'aquest tipus de roure són considerats com "la casa principal per al cérvol de Virgínia a les Grans planes del sud".[1] Quercus havardii proporciona un hàbitat per a la vida silvestre rica en comparació amb els voltants de les praderies de pastures d'herbes curtes. El manteniment de la vida silvestre i la millora de la vegetació per al pasturatge de bestiar sovint estan en conflicte, i s'ha de fer amb cura abans de realitzar el control de Quercus havardii.

Referències

  1. 1,0 1,1 1,2 1,3 1,4 Peterson, Roger S.; Boyd, Chad S. «Ecology and management of sand shinnery communities: a literature review. Gen. Tech. Rep. RMRS-GTR-16.». Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station [Consulta: 7 juliol 2009].
  2. 2,0 2,1 Oklohoma Biological Survey. Quercus havardii Rydb.
  3. 3,0 3,1 3,2 3,3 Gucker, Corey L. 2006. «Quercus havardii. In: Fire Effects Information System». U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory [Consulta: 7 juliol 2009].
  4. Flora of North America. Quercus havardii. Havard oak.
  5. R.L. McGregor Herbarium. Quercus havardii Rydb. herbarium records
  6. Flora of North America. Quercus havardii: Range Map.

Enllaços externs

 src= A Wikimedia Commons hi ha contingut multimèdia relatiu a: Quercus havardii Modifica l'enllaç a Wikidata
license
cc-by-sa-3.0
copyright
Autors i editors de Wikipedia
original
visit source
partner site
wikipedia CA

Quercus havardii: Brief Summary ( Catalan; Valencian )

provided by wikipedia CA

Quercus havardii és una espècie de roure caducifoli, de creixement baix, arbustiu, que ocupa pel voltant de 2 a 3 milions d'hectàrees al sud de les Grans planes d'Amèrica del Nord. Els clons poden arribar a centenars de milers d'anys d'antiguitat, encara que les tiges solen viure sobre el sòl només 11 o 15 anys. Els troncs d'aquest tipus de roure són generalment 1-2 m d'alçada i codominant la comunitat vegetal de gramínies mitjanes i altes, que solen ser més altes que els roures.

L'honor de portar l'epítet específic va ser pel cirurgià i botànic de l'Exèrcit dels EUA el Sr. Valery Havard, que va contribuir molt al coneixement de les plantes del sud-oest.

license
cc-by-sa-3.0
copyright
Autors i editors de Wikipedia
original
visit source
partner site
wikipedia CA

Quercus havardii

provided by wikipedia EN

Quercus havardii (common names include shinnery oak, shin oak and Havard oak) is a deciduous, low-growing, thicket-forming shrub that occupies some two million to three million hectares (7,700 to 11,600 square miles) in the southern Great Plains of North America.[2] Clones may reach hundreds to thousands of years old, although aboveground stems typically live only 11 to 15 years. Shinnery oak stems are usually 1 to 2 metres (3 feet 3 inches to 6 feet 7 inches) tall and codominate the plant community with mid- and tall-grasses, which are usually taller than the oaks.

The specific epithet honors U.S. Army surgeon and botanist Valery Havard, who contributed much to the knowledge of southwestern plants. The word "shinnery" seems to be derived from chêne (French for oak), and not from the height of the plant.[3]

Description

Form: A low shrub to 2 metres (6+12 feet) or occasionally a small tree, Q. havardii forms large clonal thickets by extending rhizomes through the sandy soil where it is usually found.[4] Rhizomes range from 3–15 centimetres (1+14–6 inches) in diameter and are concentrated in the upper 60 cm (24 in) of soil, although penetration depths of 9 m (30 ft) have been reported in shifting dunes. Lateral roots and woody rhizomes are widespread near the soil surface. At least 90% of shinnery oak's biomass is underground, and fortuitous root grafting is common. These underground stems commonly spread to form plants 3 to 15 m (10 to 49 ft) or more in diameter. Single clones are reported to cover up to 81 hectares (200 acres) and to achieve ages over 13,000 years.[2]

Flowers: Shinnery oak is monoecious with both female and male flowers borne separately on the same plant.[5] Male catkins are densely flowered, 1.5–3.8 cm long, and hang downward. Female catkins are 3–7 millimetres (1814 in) long, contain 1 to 5 flowers, and are usually axillary on young shoots. Shinnery oaks are wind pollinated, and flowering occurs in the spring.

Acorns: Acorns develop in one year, maturing in the autumn. Acorns occur alone or in clusters of 2 or 3, and are 12–25 mm (12–1 in) long by 14–18 mm wide. A scaly cup covers about 1/3 to 1/2 of the nut. On average, acorn crops are produced in 3 out of 10 years.[4]

Foliage: The leathery, highly variable leaves are grey green to olive green, have a lustrous upper surface, and are whitish and densely hairy below. The leaves are alternate, simple, with variable shape (oblong, ovate, or elliptical), and with wavy or shallowly lobed margins. Their length is 2 to 8 cm (34 to 3+18 in) and width 2 to 4 cm.[3]

Twigs: Twigs are brown or grayish, 1–2.5 mm diameter, glabrous or densely covered with short grayish or yellowish hairs, that are lost with age. The buds are dark red-brown, somewhat spherical, about 2 mm long, and sparsely pubescent.

Bark: Bark on the larger stems is light gray and scaly.

Taxonomy

Shinnery oak populations in Utah and Arizona are considered a variety of shinnery oak (Quercus havardii var. tuckeri) by some taxonomists. However, introgression of shinnery oak with Gambel oak (Quercus gambelii) and perhaps shrub live oak (Quercus turbinella) make taxonomic identification of these populations difficult.[4]

Shinnery oak hybridizes with Mohr oak (Quercus mohriana) and post oak (Quercus stellata). Post oak × shinnery oak hybrids are likely to be a result of post oak's historic range, which extended more westerly than it does today. Mohr oak × shinnery oak hybrids are restricted to habitats intermediate to those occupied by the two species. Mohr oak inhabits limestone soils, and shinnery oak occurs on deep sand soils.

Native range

Shinnery oak is native to western Oklahoma, west Texas, eastern New Mexico, and two isolated populations in southwest Kansas.[6] A variety also occurs in northeastern Arizona and southeastern Utah.[7] Sandy plains, sand dunes, and sand hills of the southern Great Plains are typical habitat.

Management

A majority of shinnery oak occurs on private land used for agriculture and/or livestock production. It is considered undesirable on grazing lands, because it competes with better livestock forage and its buds and leaves are toxic to cattle for several weeks in spring. In addition, where cotton is grown near shinnery oak, boll weevils overwinter in the oak litter and infest nearby cotton fields in spring. Thus, most research and other human effort concerning shinnery oak have been devoted to its eradication.

The use of chemical and mechanical control methods has been extensive, making it likely that shinnery oak's distribution is decreasing. Most authorities do not recommend complete eradication of shinnery oak, indicating that forage production is typically greater if some shinnery oak remains in the community. Stocking rates and rotational grazing patterns exist that reduce the incidence of shinnery oak poisoning of cattle. Excessive control of shinnery oak is controversial because it can open sandy soils to wind erosion and can conflict with wildlife-habitat quality.[2]

Shinnery oak sprouts prolifically from rhizomes soon after fire. Researchers described the communities as "extremely fire hardy".[4]

Quercus havardii resprouting

Uses

Because shinnery oak thrives in a harsh environment, it functions as a sand dune stabilizer, protecting sandy soils from wind erosion. It also provides diverse wildlife species cover and food. Collared peccaries, lesser prairie-chickens, northern bobwhites, and many other wildlife species eat shinnery oak acorns. Deer, pronghorn, and southern plains woodrats browse shinnery oak. Shinnery oak habitats are used by black-tailed jackrabbits, desert cottontails, eastern cottontails, wild turkeys, western box turtles, a diversity of arthropods, approximately 25 snake species, and approximately 10 lizard species, including the endangered sand dune lizard (Sceloporus arenicolus).[2]

Many game species also rely on shinnery oak. Scaled quail and northern bobwhites use shinnery oak habitats extensively, and shinnery oak habitats are considered "the principal home for white-tailed deer in the southern Great Plains".[2]

Shinnery oak provides rich habitat for wildlife compared with the surrounding shortgrass plains. Maintaining wildlife habitat and improving vegetation for livestock grazing are often in conflict, and should be carefully considered before undertaking control of shinnery oak.

References

  1. ^ Kenny, L., Wenzell, K., Beckman, E. (2016). "Quercus havardii". IUCN Red List of Threatened Species. 2016. Retrieved 26 December 2022.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ a b c d e Peterson, Roger S.; Boyd, Chad S. (1998). "Ecology and management of sand shinnery communities: a literature review. Gen. Tech. Rep. RMRS-GTR-16". Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Retrieved 2009-07-07.
  3. ^ a b Oklahoma Biological Survey. Quercus havardii Rydb.
  4. ^ a b c d Gucker, Corey L. (2006). "Quercus havardii". Fire Effects Information System (FEIS). US Department of Agriculture (USDA), Forest Service (USFS), Rocky Mountain Research Station, Fire Sciences Laboratory. Retrieved 2009-07-07.
  5. ^ Nixon, Kevin C. (1997). "Quercus havardii". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 3. New York and Oxford – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  6. ^ R.L. McGregor Herbarium. Quercus havardii Rydb. herbarium records
  7. ^ Flora of North America. Quercus havardii: Range Map.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Quercus havardii: Brief Summary

provided by wikipedia EN

Quercus havardii (common names include shinnery oak, shin oak and Havard oak) is a deciduous, low-growing, thicket-forming shrub that occupies some two million to three million hectares (7,700 to 11,600 square miles) in the southern Great Plains of North America. Clones may reach hundreds to thousands of years old, although aboveground stems typically live only 11 to 15 years. Shinnery oak stems are usually 1 to 2 metres (3 feet 3 inches to 6 feet 7 inches) tall and codominate the plant community with mid- and tall-grasses, which are usually taller than the oaks.

The specific epithet honors U.S. Army surgeon and botanist Valery Havard, who contributed much to the knowledge of southwestern plants. The word "shinnery" seems to be derived from chêne (French for oak), and not from the height of the plant.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Quercus havardii ( Spanish; Castilian )

provided by wikipedia ES

Quercus havardii, es una especie de roble de la familia Fagaceae que es originria de Norteamérica. Está clasificada en la Sección Quercus, que son los robles blancos de Europa, Asia y América del Norte. Tienen los estilos cortos; las bellotas maduran en 6 meses y tienen un sabor dulce y ligeramente amargo, el interior de la bellota tiene pelo. Las hojas carecen de una mayoría de cerdas en sus lóbulos, que suelen ser redondeados. Tiene una hoja caduca, es de crecimiento bajo, que forma matorral de arbustos y que ocupa unos 2 a 3 millones de hectáreas en el sur de las Grandes Planicies de América del Norte.[2]​ Los clones pueden llegar a cientos de miles de años de antigüedad, aunque por encima del suelo, los tallos suelen vivir sólo de 11 a 15 años. Los tallos son generalmente de 1-2 m de altura y codomina la comunidad vegetal con medias y altas de gramíneas, que son por lo general más altas que los robles.

Descripción

Es un arbusto bajo que alcanza un tamaño de 2 m o de vez en cuando un pequeño árbol, Q. havardii formas grandes matorrales clonales mediante la ampliación de los rizomas a través del suelo arenoso donde se encuentra por lo general.[3]​ Los rizomas miden 3-15 cm de diámetro, y se concentran en los 60 cm superiores del suelo, aunque se ha informado de profundidades de penetración de hasta 9 m. Las raíces laterales y rizomas leñosos son generalizados, cerca de la superficie del suelo. El noventa por ciento o más de la biomasa se encuentra bajo tierra, y el injerto de raíz fortuito es común. Estos tallos subterráneos comúnmente se extiende para formar plantas de 3 a 15 m de diámetro o más. Clones individuales se reportan para cubrir hasta 81 hectáreas y alcanzar edades más de 13.000 años.[2]

Quercus havardii es monoico con flores de ambos sexos por separado en la misma planta.[1]​ Los amentos masculinos están densamente florecidos con 1.5 a 3.8 cm de largo, y cuelgan hacia abajo. Los amentos femeninos son de 3-7 mm de largo, contienen de 1 a 5 flores, y son generalmente axilares en los brotes jóvenes. Quercus havardii son polinizadas por el viento, y la floración se produce en primavera. Las bellotas se desarrollan en 1 año, con vencimiento en el otoño. Las bellotas se producen solas o en grupos de 2 o 3, y miden de 12-25 mm de largo por 14 a 18 mm de ancho. Una taza escamosa cubre aproximadamente 1/3 a 1/2 de la misma. En promedio, los cultivos de bellota se producen entre los 3 y los 10 años.[3]

Las hojas son coriáceas muy variables y de color gris a verde oliva, tienen una superficie superior brillante, y son de color blanquecino y densamente peluda continuación. Las hojas son sencillas , con la variable de la forma (rectangular, oval o elíptica), y con el pelo ondulado o márgenes superficialmente lobuladas. La longitud es de 2 a 8 cm y ancho de 2 a 4 cm.[4]​ Las ramitas son de color marrón o grisáceo, con 1-2.5 mm de diámetro, glabras o densamente cubiertas de pelos cortos o grisáceo amarillento, que se pierden con la edad. Los cogollos son de color rojo oscuro marrón, algo esférico, de unos 2 mm de largo, y escasamente pubescentes.

Usos

Debido a que prospera en un ambiente duro, funciona como un estabilizador de las dunas de arena, protegiendo los suelos arenosos de la erosión del viento. También ofrece alimento y cubierta a diversas especies de fauna silvestre como: Pecari tajacu, Tympanuchus pallidicinctus, Colinus virginianus, y muchas otras especies de vida silvestre que comen sus bellotas. Odocoileus virginianus, Antilocapra americana, y Neotomas. Su hábitat es usado por Lepus californicus, Sylvilagus audubonii, Sylvilagus floridanus, Meleagris gallopavo, Terrapene ornata, una diversidad de artrópodos, aproximadamente 25 especies de serpientes y aproximadamente a 10 especies de lagartos, entre ellas el lagarto duna de arena en peligro (Sceloporus arenicolus).[2]

Muchas especies de caza se basan también en Quercus havardii; Callipepla squamata utiliza el hábitats del roble ampliamente, y los hábitats se consideran "la residencia principal de los ciervos de cola blanca en el sur de las Grandes Planicies".[2]

Quercus havardii ofrece ricos hábitats para la vida silvestre en comparación con los que rodean las llanuras de pastos cortos. El mantenimiento de hábitat de la fauna y la mejora de la vegetación para el pastoreo de ganado están a menudo en conflicto, y debe ser considerado cuidadosamente antes de realizar el control de roble Quercus havardii.

Taxonomía

Quercus havardii fue descrita por Per Axel Rydberg y publicado en Bulletin of the New York Botanical Garden 2(6): 213, pl. 29, f. 2. 1901.[5][6][7]

Etimología

Quercus: nombre genérico del latín que designaba igualmente al roble y a la encina.

havardii: epíteto otorgado en honor del cirujano del Ejército de EE.UU. y botánico Valery Havard, quien contribuyó mucho al conocimiento de las plantas del suroeste.[4]

Referencias

  1. a b Flora of North America. Quercus havardii. Havard oak.
  2. a b c d Peterson, Roger S.; Boyd, Chad S. (1998). «Ecology and management of sand shinnery communities: a literature review. Gen. Tech. Rep. RMRS-GTR-16.». Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Consultado el 7 de julio de 2009.
  3. a b Gucker, Corey L. 2006. «Quercus havardii. In: Fire Effects Information System». U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. Consultado el 7 de julio de 2009.
  4. a b «Oklahoma Biological Survey. Quercus havardii Rydb.». Archivado desde el original el 17 de diciembre de 2013. Consultado el 11 de julio de 2014.
  5. «Quercus havardii». Tropicos.org. Missouri Botanical Garden. Consultado el 11 de julio de 2014.
  6. «Quercus havardii». Royal Botanic Gardens, Kew: World Checklist of Selected Plant Families. Consultado el 11 de julio de 2014.
  7. «Quercus havardii». The Plant List. Consultado el 11 de julio de 2014.

 title=
license
cc-by-sa-3.0
copyright
Autores y editores de Wikipedia
original
visit source
partner site
wikipedia ES

Quercus havardii: Brief Summary ( Spanish; Castilian )

provided by wikipedia ES

Quercus havardii, es una especie de roble de la familia Fagaceae que es originria de Norteamérica. Está clasificada en la Sección Quercus, que son los robles blancos de Europa, Asia y América del Norte. Tienen los estilos cortos; las bellotas maduran en 6 meses y tienen un sabor dulce y ligeramente amargo, el interior de la bellota tiene pelo. Las hojas carecen de una mayoría de cerdas en sus lóbulos, que suelen ser redondeados. Tiene una hoja caduca, es de crecimiento bajo, que forma matorral de arbustos y que ocupa unos 2 a 3 millones de hectáreas en el sur de las Grandes Planicies de América del Norte.​ Los clones pueden llegar a cientos de miles de años de antigüedad, aunque por encima del suelo, los tallos suelen vivir sólo de 11 a 15 años. Los tallos son generalmente de 1-2 m de altura y codomina la comunidad vegetal con medias y altas de gramíneas, que son por lo general más altas que los robles.

license
cc-by-sa-3.0
copyright
Autores y editores de Wikipedia
original
visit source
partner site
wikipedia ES

Quercus havardii ( French )

provided by wikipedia FR

Quercus havardii, de nom commun Chêne de Havard, est une espèce d'arbustes nord-américains de la famille des Fagaceae et du genre Quercus (Chênes).

Description

 src=
Inflorescences.

Quercus havardii est un arbuste bas jusqu'à 2 m ou parfois un petit arbre. Il forme de grands fourrés clonaux en étendant les rhizomes à travers le sol sableux. Les rhizomes mesurent de 3 à 15 cm de diamètre et se concentrent dans les 60 cm supérieurs du sol, bien que des profondeurs de pénétration de 9 m sont recensées. Les racines latérales et les rhizomes ligneux sont répandus près de la surface du sol. 90% ou plus de la biomasse du chêne est sous terre et la greffe de racines fortuite est courante. Ces tiges souterraines s'étendent généralement pour former des plantes de 3 à 15 m ou plus de diamètre[1]. Les clones uniques couvriraient jusqu'à 81 ha. Alors que les tiges aériennes ne vivent généralement que 11 à 15 ans, ils atteindraient des âges de plus de 13 000 ans[2].

Les feuilles coriaces et très variables sont vert gris à vert olive, ont une face supérieure lustrée et sont blanchâtres et densément poilues en dessous. Les feuilles sont alternes, simples, de forme variable (oblongues, ovales ou elliptiques), et avec des marges ondulées ou peu lobées. La longueur est de 2 à 8 cm et la largeur de 2 à 4 cm.

Les rameaux sont bruns ou grisâtres, de 1 à 2,5 mm de diamètre, glabres ou densément couverts de courts poils grisâtres ou jaunâtres, qui se perdent avec l'âge. Les bourgeons sont brun-rouge foncé, quelque peu sphériques, d'environ 2 mm de long et peu pubescents. L'écorce des grosses tiges est gris clair et écailleuse.

Quercus havardii est monoïque avec des fleurs femelles et mâles portées séparément sur la même plante. Les chatons mâles sont densément fleuris, mesurent 1,5 à 3,8 cm de long et pendent vers le bas. Les chatons femelles mesurent 3 à 7 mm de long, contiennent 1 à 5 fleurs et sont généralement axillaires sur les jeunes pousses. Les chênes sont pollinisés par le vent et la floraison a lieu au printemps.

Les glands se développent en 1 an et mûrissent à l'automne. Les glands se présentent seuls ou en grappes de 2 ou 3, et mesurent de 12 à 25 mm de long sur de 14 à 18 mm de large. Une cupule écailleuse couvre environ un tiers à la moitié de la coque[1]. En moyenne, les cultures de glands sont de 3 en 10 ans.

Répartition

 src=
Aire de répartition de Quercus havardii.

Quercus havardii occupe environ 2 à 3 millions d'hectares dans le sud des Grandes Plaines d'Amérique du Nord[2]. Il est originaire de l'ouest de l'Oklahoma, de l'ouest du Texas, de l'est du Nouveau-Mexique et de deux populations isolées du sud-ouest du Kansas. Une variété se produit également dans le nord-est de l'Arizona et le sud-est de l'Utah.

Taxonomie

Les populations de Quercus havardii de l'Utah et de l'Arizona sont considérées comme une variété (Quercus havardii var. Tuckeri) par certains taxonomistes, d'autres les considèrent comme l'espèce Quercus welshii (en). Cependant, l'introgression de Quercus havardii avec le Quercus gambelii et peut-être Quercus turbinella rend l'identification taxonomique de ces populations difficile.

Le Quercus havardii s'hybride avec Quercus mohrianaet Quercus stellata. Les hybrides Quercus stellata × Quercus havardii sont probablement le résultat de l'aire de répartition historique deQuercus stellata, qui s'étendait plus à l'ouest qu'aujourd'hui. Les hybrides de Quercus mohriana × Quercus havardii sont limités aux habitats intermédiaires à ceux occupés par les deux espèces. Quercus mohriana habite les sols calcaires et Quercus havardii se produit sur les sols sableux profonds.

L'épithète est un hommage au botaniste Valery Havard (en).

Écologie

 src=
Jeunes Quercus havardii sur sol sableux.

Les plaines de sable, les dunes de sable et les collines de sable du sud des Grandes Plaines sont des habitats typiques. Le chêne cohabite avec des plantes comme Artemisia filifolia.

Comme Quercus havardii se développe dans un environnement difficile, il fonctionne comme un stabilisateur de dunes de sable, protégeant les sols sableux de l'érosion éolienne. Il fournit également une couverture et de la nourriture à des espèces sauvages. Le pécari à collier, le Tétras pâle, le Colin de Virginie et de nombreuses autres espèces sauvages mangent les glands. Le cerf de Virginie, Antilocapra americana et les Neotoma broutent les feuilles. Quercus havardii sert d'habitat au Lièvre de Californie, au Lapin d'Audubon, au Lapin à queue blanche, au Rat-kangourou d'Ord, au Dindon sauvage, à Terrapene ornata, une diversité d'arthropodes, environ 25 espèces de serpents et environ 10 espèces de lézards, y compris Sceloporus arenicolus[2].

Quercus havardii fournit un habitat riche pour la faune par rapport aux plaines à herbes courtes environnantes. Le maintien de l'habitat faunique et l'amélioration de la végétation pour le pâturage du bétail sont souvent en conflit et doivent être soigneusement pris en compte avant d'entreprendre le contrôle de Quercus havardii.

Une majorité de Quercus havardii se trouve sur des terres privées utilisées pour l'agriculture et/ou la production animale. Il est considéré comme indésirable sur les pâturages, car il est en concurrence avec le fourrage du bétail et ses bourgeons et ses feuilles sont toxiques pour le bétail pendant plusieurs semaines au printemps. De plus, là où le coton est cultivé près de Quercus havardii, le charançon du cotonnier hiverne dans la litière de chêne et infeste les champs de coton voisins au printemps. Ainsi, la plupart des recherches et autres efforts humains concernant Quercus havardii sont consacrés à son éradication.

L'utilisation de méthodes de contrôle chimiques et mécaniques fait qu'il est probable que la répartition de Quercus havardii diminue. La plupart des autorités ne recommandent pas l'éradication complète de Quercus havardii, ce qui indique que la production fourragère est généralement plus élevée s'il reste des arbres de Quercus havardii. Il existe des taux de charge et des schémas de rotation des pâturages qui réduisent l'incidence de l'empoisonnement des bovins par le chêne brillant. Un contrôle excessif de Quercus havardii est controversé, car il peut ouvrir les sols sableux à l'érosion éolienne et peut entrer en conflit avec la qualité de l'habitat faunique[2].

Quercus havardii pousse abondamment à partir des rhizomes peu après le feu. Les chercheurs décrivent les communautés comme extrêmement résistantes au feu.

Notes et références

  • (en) Cet article est partiellement ou en totalité issu de l’article de Wikipédia en anglais intitulé .
  1. a et b « Quercus havardii » (consulté le 25 septembre 2020)
  2. a b c et d (en) Roger Peterson, Chad S. Boyd, « Ecology and management of sand shinnery communities: a literature review », General Technical Report,‎ 2000 (lire en ligne)

license
cc-by-sa-3.0
copyright
Auteurs et éditeurs de Wikipedia
original
visit source
partner site
wikipedia FR

Quercus havardii: Brief Summary ( French )

provided by wikipedia FR

Quercus havardii, de nom commun Chêne de Havard, est une espèce d'arbustes nord-américains de la famille des Fagaceae et du genre Quercus (Chênes).

license
cc-by-sa-3.0
copyright
Auteurs et éditeurs de Wikipedia
original
visit source
partner site
wikipedia FR

Quercus havardii ( Polish )

provided by wikipedia POL
Commons Multimedia w Wikimedia Commons

Quercus havardii Rydb. – gatunek roślin z rodziny bukowatych (Fagaceae Dumort.). Występuje naturalnie w Stanach Zjednoczonych – w Utah, Kolorado, Kansas, Nowym Meksyku, Oklahomie oraz Teksasie[3][4].

Morfologia

Pokrój
Zrzucający liście krzew dorastający do 0,5–10 m wysokości. Kora jest papierowa, łuszcząca się i ma szarą barwę[4].
Liście
Blaszka liściowa ma podługowaty, owalny, odwrotnie jajowaty, eliptyczny lub lancetowaty kształt. Mierzy 5–10 cm długości oraz 2–5 cm szerokości, jest delikatnie ząbkowana na brzegu, ma nasadę od zaokrąglonej do klinowej i zaokrąglony lub tępy wierzchołek. Ogonek liściowy jest nagi i ma 7 mm długości[4].
Owoce
Orzechy zwane żołędziami o jajowatym kształcie, dorastają do 15–23 mm długości i 12–15 mm średnicy. Osadzone są pojedynczo w miseczkach w kształcie kubka, które mierzą 4–12 mm długości i 10–15 mm średnicy. Orzechy otulone są w miseczkach do 20–40% ich długości[4].

Biologia i ekologia

Rośnie na piaszczystych wydmach. Występuje na wysokości od 500 do 1500 m n.p.m.[4]

Przypisy

  1. Stevens P.F.: Angiosperm Phylogeny Website (ang.). 2001–. [dostęp 2017-04-04].
  2. Quercus havardii Rydb. (ang.). The Plant List. [dostęp 4 kwietnia 2017].
  3. Comprehensive Report Species - Quercus havardii (ang.). NatureServe. [dostęp 4 kwietnia 2017].
  4. a b c d e Quercus havardii (fr.). Plantes & botanique. [dostęp 4 kwietnia 2017].
license
cc-by-sa-3.0
copyright
Autorzy i redaktorzy Wikipedii
original
visit source
partner site
wikipedia POL

Quercus havardii: Brief Summary ( Polish )

provided by wikipedia POL

Quercus havardii Rydb. – gatunek roślin z rodziny bukowatych (Fagaceae Dumort.). Występuje naturalnie w Stanach Zjednoczonych – w Utah, Kolorado, Kansas, Nowym Meksyku, Oklahomie oraz Teksasie.

license
cc-by-sa-3.0
copyright
Autorzy i redaktorzy Wikipedii
original
visit source
partner site
wikipedia POL

Quercus havardii ( Vietnamese )

provided by wikipedia VI

Quercus havardii là một loài thực vật có hoa trong họ Cử. Loài này được Rydb. miêu tả khoa học đầu tiên năm 1901.[1]

Hình ảnh

Chú thích

  1. ^ The Plant List (2010). Quercus havardii. Truy cập ngày 4 tháng 6 năm 2013.

Tham khảo


Bài viết Họ Cử này vẫn còn sơ khai. Bạn có thể giúp Wikipedia bằng cách mở rộng nội dung để bài được hoàn chỉnh hơn.
license
cc-by-sa-3.0
copyright
Wikipedia tác giả và biên tập viên
original
visit source
partner site
wikipedia VI

Quercus havardii: Brief Summary ( Vietnamese )

provided by wikipedia VI

Quercus havardii là một loài thực vật có hoa trong họ Cử. Loài này được Rydb. miêu tả khoa học đầu tiên năm 1901.

license
cc-by-sa-3.0
copyright
Wikipedia tác giả và biên tập viên
original
visit source
partner site
wikipedia VI