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One population from San Juan County, Utah, with larger fruit but otherwise not differing from typical Quercus gambelii , has been recognized as Q . gambelii var. bonina Welsh. Unless other characters are found to support this segregation, the plants are best not treated as a formal taxon, particularly considering the extensive variation and hybridization associated with Q . gambelii throughout its range.
Numerous putative hybrid swarms occur throughout the range of Quercus gambelii that involve a number of suspected parental species. Most of these populations have, at one time or another, been referred to Quercus undulata Torrey. The putative hybrids have serrate or shallowly lobed leaves and considerable variation in habit, leaf pubescence, and acorn morphology. J. M. Tucker (1961, 1969, 1971) and J. M. Tucker et al. (1961) have identified the major components of the Q . undulata complex as Q . turbinella (western Utah and northwestern Arizona, and central Colorado), Q . grisea (New Mexico and southern Colorado), Q . havardii (southeastern Utah and northwestern Arizona), Q . mohriana (northeastern and southern New Mexico), Q . arizonica (central Arizona), and Q . muhlenbergii (eastern and central New Mexico). Quercus macrocarpa has been implicated as a parent of variable populations in New Mexico (J. M. Tucker and J. R. Maze 1966). Because of the complex variability in these populations, no effort has been made to treat them separately here; indeed, it would be impossible to produce usable keys if these were included as formal taxa.
Hybrids derived from Quercus gambelii and an evergreen species are often semideciduous, retaining a variable portion of green or brownish leaves over the winter.
Quercus gambelii was used medicinally by the Navaho-Ramah to alleviate postpartum pain, as a cathartic, as a ceremonial emetic, and as a life medicine (D. E. Moerman 1986).
Postfire stand recovery time varies according to fire severity, climatic factors, and site characteristics. Recovery after fire is fastest on
warm, south-facing slopes at low elevations [125].
Postfire regrowth was greatest the 1st year following a summer (July) and fall (September to October) fire between 4,600 and 6,400 feet
(1,402-1,950 m) in northern Utah. August 1 postfire growth was 16 to 18 inches (41-46 cm), with 2nd-year growth at 4 to 8 inches (10-20 cm) [13].
Other studies show similar, rapid Gambel oak recovery from fire. New shoots with flowers were produced 26 days after an August fire in Orem Park, Provo Canyon, Utah, on stems
that were defoliated but not killed
[92]. Gambel oak shrublands were nearly half-covered with resprouting oaks 1 year after an August fire in Mesa Verde National Park, Colorado [72].
Also in Mesa Verde National Park, Gambel oak crown sprouted and leafed within a few months after a mid-July to August
lightning-ignited wildfire at 7,500 feet (2,286 m) [61]. Resprouting of Gambel oak after an October prescribed burn in Grand Mesa National Forest, Colorado, was greatest
at the 1st postburn growing season, decreasing the 2nd and following growing seasons.
The Gambel oak type of the Intermountain West provides good winter habitat for mule deer and offers high cover potential [107]. However, tall, dense stands of Gambel oak provide poor winter ranges for deer and elk. Tall Gambel oak reaches beyond browse height of deer and elk and leads to shade-induced suppression of forbs and grasses [122]. Dense stands may also exclude some big game animals. In White River Plateau, Colorado, Boyd [21] observed Gambel oak densities exceeding 51% canopy cover, which physically excluded elk.
The degree to which Gambel oak provides cover for wildlife species is as follows [55] :
CO UT WY Pronghorn ---- Fair Poor Elk Good Good Good Mule deer Good Good Good White-tailed deer Good ---- Good Small mammals Good Good Good Small nongame birds Good Good Good Upland game birds Good Good Good Waterfowl ---- Poor PoorGambel oak occurs as clones [65] of shrubs in dense patches 3 to 20 feet (0.91-6.1 m) tall, often with a central thicket rising above the others [13], and as widely dispersed trees [43] up to 75.5 feet (23 m) tall [38]. Clones show uniform characteristics in shape, pubescence, and color [92]. Variability in life form corresponds with relative levels of water stress; stunted shrubs are present on xeric sites with moderate-sized trees found in wetter locations [54,107]. Gambel oak bark ranges from 0.5 to 0.75 inch (1.2-1.9 cm) thick. The bark is deeply divided into broad, irregular, often connected, flat ridges. Branches are slender and coated with short, pale, rust-colored hairs when 1stappearing [13]. Leaves of Gambel oak are highly variable, differing in outline, texture, lobing [13,92], pubescence, and size. Acorns are sessile or pedunculate [92], with an oval shape, usually 0.75 inch (1.9 cm) long and 0.63 inch (1.6 cm) broad [13].
The underground system of Gambel oak consists of a lignotuber with deep-feeding roots [33]. Lignotubers possess many scattered adventitious buds [213]. Clones are interconnected with rhizomes [198] that intertwine with lignotubers. Root grafting is common; root-endomycorrhizal associations may also occur [213].
Gambel oak possesses morphological and physiological adaptations to drought [1,116]. Deep roots, xeromorphic leaves and efficient water transport contribute to effective drought tolerance [1].
The growth rate of Gambel oak may vary with age. Barger and Ffolliott [14] report Gambel oak grows rapidly in height and diameter at early stages of life, with growth rates steadily declining with age. In contrast, in central Utah study Wagstaff [206] observed little change in growth rate of Gambel oak diameter during the 1st 100 years of life.
Ecological characteristics compiled by Loehle [132], are summarized below:
Typical age of mortality (years) Maximum Longevity (years) Specific gravity Relative growth rate Relative Decay Resistance 90 120 0.62 Medium HighGambel oak occurs from New Mexico west to Arizona and southwestern Nevada and north to Utah, Colorado and southeastern Wyoming [13]. Isolated patches occur in Texas [92]. The Natural Resource Conservation Service provides a map of Gambel oak's distribution in the United States (https://plants.usda.gov /plants/cgi_bin/topics.cgi).
Gambel oak is a fire-adapted species [143]. It responds to fire by vegetative sprouting from the lignotuber and rhizomes. Tree forms may survive low-severity fire [92].
Fire frequency within Gambel oak stands varies with plant associates. In most associations, little fuel is available for fires to occur in successive growing seasons [44,144]. Pure Gambel oak stands in southwestern Colorado burn most readily between October 1 and snowfall, when dead leaves remain on branches and the National Fire Danger Rating System burning index is between 40 and 75 [22]. Fall fires carry most readily through pure Gambel oak stands after leaf senescence but before leaf fall [144]. Dry, windy weather readily spreads flames through oak crowns [22]. Gambel oak stands burn well during dry summer conditions, especially on steep, south aspects [22,142].
Fire succession: Fire in Gambel oak stands may promote a brief grass-forb stage depending upon fire intensity and frequency [44]. In most situations, Gambel oak resprouts vigorously the 1st growing season following fire [13,26,44,53,76,143,144]. If successive fires occur at this stage, Gambel oak stands may be reduced to a grass-forb stage [44,144]. Repeated fires in Gambel oak ranges may deplete stored resources of rhizomes and lignotubers [144]. As sprouts continue to grow, natural thinning occurs, adding dead stems to the fuel. Fire occurring at this stage also sends Gambel oak stands back to a seral grass-forb stage. In absence of fire, sprouts form young poles. At this stage fires are stand replacement, either creating openings within stands for colonization by resprouts or a complete recycling back to a grass-forb stage. In the absence of fire, Gambel oak stands reach maturity in 60 to 80 years. Fire response in mature stands is similar to that in young poles. A severe fire will recycle the stand; low-severity fires create openings for resprouts. At 80 years Gambel oak stems die naturally, creating more openings for sprouts [44].
The Utah woodlands at 5,500 to 7,800 feet (1,676-2,377 m), where Gambel oak and/or bigtooth maple are dominant, codominant, or long-term seral dominants, have low combustibility. However, environmental conditions occasionally permit severe wildfires [22]. Gambel oak leaves killed by a late spring freeze may provide dried tinder during summer or early fall [214]. With increasing bigtooth maple cover, fire susceptibility lessens through relatively rapid decomposing leaf litter and a reduced understory [22]. Susceptibility increases where conifers are encroaching, due to resinous foliage and persistent litter [92].
Fire in ponderosa pine stands of Arizona may convert stands to thickets of Gambel oak [170], initiating a Gambel oak successional stage after the competing ponderosa pine overstory is removed [44,53]. Dense understories of Gambel oak may serve as ladder fuels that carry fire to overstory tree crowns, increasing fire risk to ponderosa pine [22]. A detailed description of fire-induced succession within ponderosa pine-Gambel oak habitat types can be found in Crane [44].
FIRE REGIMES:
In Zion National Park, Utah, fires are more frequent in ponderosa pine stands with a Gambel oak understory than in Gambel oak-dominated stands without ponderosa pine litter [144]. The mean historical fire return interval in ponderosa pine-Gambel oak forests near Tucson, Arizona, was 3.7 years between 1637 and 1883. Only a single fire scar was recorded between 1883 and 1951. With fire exclusion, Gambel oak and ponderosa pine densities have increased. A reconstruction of 1883 presettlement forest structure compared with contemporary forest structure from a 1994/1995 inventory at Camp Navajo, Arizona, is summarized below [77]:
Species Presettlement mean Contemporary mean Trees/ha Ponderosa pine 65.3 720.2 Gambel oak 79.4 471.4 Basal area (m2/ha) Ponderosa pine 11.7 18.2 Gambel oak 1.0 6.6Gambel oak is a seral species in quaking aspen, pinyon-juniper, and mixed-conifer forests [44]. Gambel oak occupies a seral postfire successional stage in pinyon-juniper woodlands [61,218]. Reestablishment of pinyon pine and most juniper species after disturbance is dependent entirely upon seed production. The vegetative reproductive capabilities of Gambel oak provide it with an inherent postfire advantage. Gambel oak occupies a seral postfire stage within pinyon-juniper woodlands of Mesa Verde, Colorado. Gambel oak dominates for approximately 25 postfire years, and may persist up to 100 years before canopy suppression by pinyon pine and juniper species [62]. Floyd [71] presents the Gambel oak vegetation type as successional in Colorado, altering the habitat and facilitating invasion and eventual succession to pinyon-juniper woodland. Within Douglas-fir forests of the White Mountains of Colorado, Hanks and Dick-Peddie [89] describe Gambel oak as occupying a postfire successional stage that may persist up to 100 years before being shaded out by coniferous overstory. Within the Huachuca Mountains of Arizona, Gambel oak was found in Douglas-fir communities after fire. As Gambel oak matured, Douglas-fir seedlings occupied the understory, suggesting eventual return to Douglas-fir dominance [23]. Hypothetical postfire succession in Rocky Mountain habitats where Gambel oak occurs is described by Crane [44].
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". The following table provides fire-return intervals in some communities where Gambel oak occurs [27]:
Community or Ecosystem Dominant Species Fire Return Interval Range (years) mountain-mahogany-Gambel oak scrub Cercocarpus ledifolius-Quercus gambelii western juniper Juniperus occidentalis 20-70 Rocky Mountain juniper J. scopulorum 27]In mature Gambel oak stands ( > 60 years), severe fires top-kill all or most of the stand; low-severity fires create openings for sprouts [144].
Gambel oak leaf moisture content varies greatly from year to year. Moisture content decreases from May to August [160]; August foliage has less than half the moisture of May foliage [161]. Within Waterton Canyon, Colorado, the moisture content of Gambel oak leaves decreased significantly (p < 0.001) in both the upper and lower canopy from May to August. This was true regardless of aspect and elevation. Ogle [160] constructed a model to predict fire behavior in relation to fuel moisture in Gambel oak.
Gambel oak produces a large amount of leaf litter that contributes, in most cases, 70% of total stand litter. In Utah, accumulated litter biomass of approximately 33,335 pounds per acre (37,348 kg/ha) was about equivalent to the bole biomass of 36,328 pounds per acre (40,702 kg/ha) [38].
The distribution of belowground nitrogen (kg/ha) and the percent of total belowground nitrogen was evaluated in a Gambel oak stands near Ephraim, Utah [199]:
Aboveground kg/ha % of N capital Leaves 43 0.45Live Branches
19 0.20Stem
124 1.3 Dead branches 40 0.43 Dead down 30 0.30 Standing dead 55 0.60 Litter 582 6.2 Belowground Soil 8455 87.9 Roots 240 2.6Based on this data, harvest followed by broadcast burning may result in a 10% loss in nitrogen capital depending upon fire intensity [199].
Fire alters the plant community in which Gambel oak occurs. Gambel oak communities are usually tolerant of fire, but herbage yields of associated species do not appear to improve [25]. Frequency and cover of major plant species on Gambel oak-dominated sites in oak brush near Wasatch Mountains State Park, Utah, were evaluated 1 year after an August wildfire [166]:
Unburned Cover Burn Species Frequency (%) (%) Frequency (%) Cover (%) Gambel oak 100 51.12 92.8 38.36 pale agoseris (Agoseris glauca) 11.8 1.06 0.90 < 0.01 bluebunch wheatgrass 29.40 0.59 0 0 Saskatoon serviceberry (Amelanchier alnifolia) 23.50 1.09 8.1 0.95 big sagebrush 17.60 1.09 0 0 China aster (Callistephus chimensis) 5.90 0.03 0 0 cheatgrass 23.5 4.17 18.90 0.16 lambsquarters (Chenopodium album) 0 0 24.30 1.24 narrowleaf goosefoot (C. leptophyllum) 5.90 0.03 19.8 0.39 maiden blue-eyed Mary (Collinsia parciflora) 29.40 0.15 27.9 0.32 tapertip hawksbeard (Crepis acuminata) 47.10 1.38 3.60 0.02 stickywilly 11.80 0.21 24.30 0.69 Brown's pea (Lathyrus spp.) 58.80 2.59 7.20 0.30 biscuitroot (Lomatium triternatum) 35.30 0.77 1.8 0.01 tansyaster (Machaerantera canescens) 0 0 0.9 0.03 Kentucky bluegrass 52.90 16.81 17.1 1.23 bushy knotweed (Polygonum ramosissimum) 0 0 6.3 0.03 chokecherry 29.40 8.38 10.80 0.84 threeawn goldenrod (Solidago velutina) 0 0 2.7 0.19 mullein (Verbascum thapsus) 0 0 19.8 1.2 goldeneye (Heliomeris multiflora) 0 0 24.3 0.86Control: Fall burning provides the least amount of Gambel oak control. Gambel oak is dormant in the fall and total nonstructural carbohydrate reserves are at their peak [137]. Gambel oak is most severely harmed by successive fires when carbohydrate reserves are low. Top-killing Gambel oak in the summer may produce resprouts within 6 weeks. However, by fall, resprouts are still immature and carbohydrate recovery cannot begin until the following spring leaf-out, producing a 9- to 10-month period without carbohydrate replacement. Control may occur though carbohydrate stress imposed by 2 summer burns. However, effective burning may require biennial treatments due to light litter accumulation within a single growing season [94].
Observations within a ponderosa pine stand in southwestern Colorado at 7,600 feet (2,316 m) suggest frequent burning during mid-August provides control for Gambel oak. Vigorous Gambel oak sprouting was observed regardless of burn season. Twice-burned spring and fall treatments resulted in resprout densities equal to once-burned areas. Twice-burned summer treatments resulted in decreased oak density, frequency, and cover. Resprouts after twice-burned summer treatments were confined to top-killed oak thickets; sprouting after fall and spring burns was not restricted; and previous Gambel oak thicket boundaries were extended[94]. Frischknect and Plummer [76] suggest seeding competitive grasses after fire, but additional studies are required to substantiate findings [92].
The upper and lower limits of Gambel oak's range are established by the Arizona monsoons that generates a gradient of increasing cold stress in winter and spring and a summer drought stress with increasing latitude [175]. Gambel oak prefers a mean annual temperature of 44.6 to 50 degrees Fahrenheit (7-10 oC) with winter temperatures below negative 0.4 degrees Fahrenheit (-18 oC) [39]. Gambel oak does not occur in areas where winter precipitation falls below 10 inches (250 mm) or where subfreezing temperatures persist for long periods of time [35]. Annual mean precipitation measured over 14 years (1934 to 1948) at 7,655 feet (2,333 m) within Gambel oak habitats of the mountain brush zone was 20.10 inches (510 mm) [134]. Throughout its distribution Gambel oak occurs between 3,250 and 10,200 feet (990-3,110 m) [92]. Elevation limits are the widest at the southern extent, narrowing northward [155]. A preference for south slopes was observed between 8,200 and 8,700 feet (2,500-2,650 m) in southwestern New Mexico [41]. At 7,500 to 8,000 feet (2,286-2,438 m) in Mount Livermore, Texas, Gambel oak occurs on ledges and bordering talus slopes [100].
Several environmental parameters were evaluated in Gambel oak stands, comparing understory and open areas between oaks in the lower Unita Mountains, Utah. Elevation is 7,218 feet (2,200 m); slope is 10% with an 185o exposure. Mean annual precipitation is 17.7 inches (450 mm), 60% of which is received in winter [212]. Litter was deeper, shrubs had greater cover, and light was less intense under Gambel oak:
Understory Open area Litter depth (cm) 2.3 0.2 Perennial forbs (%) 15.6 27.4 Annuals (%) 32.9 40 Shrubs (%) 27.7 18.4 Light intensity1 (foot candles) 76 242 1 Light intensity was measured in July from 12 to 2 pm.Elevational ranges of Gambel oak are:
southwestern Colorado: 4,000 to 8,500 feet (1200-2550 m) [93]
Utah: 5,500 to 7,500 feet (1700-2300 m) [26,40]
217 Aspen
220 Rocky Mountain juniper
237 Interior ponderosa pine
239 Pinyon-juniper
241 Western live oak
FRES20 Douglas-fir
FRES21 Ponderosa pine
FRES23 Fir-spruce
FRES29 Sagebrush
FRES33 Southwestern shrubsteppe
FRES34 Chaparral-mountain shrub
FRES35 Pinyon-juniper
FRES36 Mountain grasslands
FRES40 Desert grasslands
K018 Pine-Douglas-fir forest
K019 Arizona pine forest
K020 Spruce-fir-Douglas-fir forest
K021 Southwestern spruce-fir forest
K023 Juniper-pinyon woodland
K031 Oak-juniper woodland
K032 Transition between K031 and K037
K037 Mountain-mahogany-oak scrub
K038 Great Basin sagebrush
K055 Sagebrush steppe
K057 Galleta-threeawn shrubsteppe
K058 Grama-tobosa shrubsteppe
107 Western juniper/big sagebrush/bluebunch wheatgrass
109 Ponderosa pine shrubland
207 Scrub oak mixed chaparral
210 Bitterbrush
401 Basin big sagebrush
402 Mountain big sagebrush
403 Wyoming big sagebrush
404 Threetip sagebrush
405 Black sagebrush
408 Other sagebrush types
411 Aspen woodland
412 Juniper-pinyon woodland
413 Gambel oak
415 Curlleaf mountain-mahogany
416 True mountain-mahogany
417 Littleleaf mountain-mahogany
418 Bigtooth maple
420 Snowbrush
421 Chokecherry-serviceberry-rose
503 Arizona chaparral
504 Juniper-pinyon pine woodland
505 Grama-tobosa shrub
509 Transition between oak-juniper woodland and mahogany-oak association
733 Juniper-oak
734 Mesquite-oak
Fire may top-kill Gambel oak [26]. Gambel oak habit and community structure affect susceptibility to fire. Tree forms are less likely to be top-killed in a low-severity fire compared to shrubs with branches closer to the burning surface fuels [92].
Gambel oak is an ecologically important species providing food and shelter for many wildlife species. Type and degree of wildlife use corresponds with Gambel oak habit. Brushy growth forms (thickets less than 25 ft2 (2.3 m2) and stems less than 15 feet (4.57 m) tall) are utilized as browse by big game and provide habitat for rabbits and rodents. Young pole stands provide sites for foliage-nesting birds. Mature growth forms provide maximum acorn yield for squirrels, birds, elk, and deer. Old stands containing large amounts of dead crown and hollow boles or limbs provide nesting sites for small mammals and birds [119].
Avian: Gambel oak acorns are an important mast crop in many areas. Acorns are a preferred food for band-tailed pigeons during fall and winter. Merriam turkeys also utilize acorns as a major part of their diet [141]. Abert's squirrels feed upon Gambel oak acorns [164]. When a good crop is available, acorns may provide up to 40% of Abert's squirrel fall diet [186]. Patton and others [163] observed squirrels using hollow Gambel oaks over 10 inches (25.4 cm) d.b.h. as nesting sites. Abert's squirrels prefer ponderosa pine forests (201 to 250 trees per acre) where Gambel oak is within a 12 to 14 inch d.b.h. class occurring as 1or 2 trees per acre [162].
Gambel oak trees within the ponderosa pine-Gambel oak forests of Arizona provide perching and nest sites for the Mexican spotted owl [81,82]. Illegal cutting of large oak trees within these forests is considered a serious problem for Mexican spotted owl management [79]. Gambel oak is used significantly more (p< 0.01) by juvenile Mexican spotted owls as roosts during dispersal in the fall (August-October) than in winter (November-April) [80]. Conifer/oak forests with relatively high densities of Gambel oak along canyon bottoms of New Mexico are preferred roost sites for Mexican spotted owls [101].
Within a Gambel oak brush community in northern Utah, Marti [140] observed 6 permanent residents: California quail, ring-necked pheasants, scrub jays, black-billed magpies, black-capped chickadees, and rufous-sided towhees. Marti also provides a complete list of birds observed and found nesting.
Mountain shrub habitats where Gambel oak is codominant with serviceberry provide a summer habitat for Columbia sharp-tailed grouse of northwestern Colorado [85]. In Utah, Gambel oak may provide nesting sites for sharp-shinned hawks [165]. Pygmy owls inhabit ponderosa pine-Gambel oak forest types within the Dixie National Forest, Utah [216].
Big game: Gambel oak is a major forage species for deer and elk in Utah [147]. Gambel oak is moderately used, relative to other forage and browse species, by Rocky Mountain mule deer in winter and spring with heavier use occurring in summer and fall [124]. In its southern range, Gambel oak is a desirable species for desert mule deer and white-tailed deer in the San Cayetano and Dos Cabezas mountains of southeastern Arizona. Greatest use of Gambel oak occurs mid-July to October, with white-tailed deer showing greater utilization than mule deer. Gambel oak, however, is not located in habitats used by mule and white-tailed deer of Arizona during the winter [11].
Gambel oak communities in Colorado provide important winter ranges for big game animals [130]. Based upon a review of 3 studies, Kufeld [121] reports Gambel oak as highly valuable winter forage for Rocky Mountain elk. Smith [181] and Smith and Hubbard [183] monitored winter forage preference of deer in Utah. Gambel oak ranked 7th out of 17 forage species based on time spent browsing and plant weight consumed. Mule deer and white-tailed deer utilized new growth and sprouts as forage [107,171]. Gambel oak ranges in southwestern Colorado provide the majority of black bear spring habitat [86] and fall food for black bear in southwestern Colorado [86].
In Colorado, bighorn sheep utilize Gambel oak as a minor component of their summer diet. On low elevation summer ranges, Gambel oak may comprise up to 17% of the June diet [177], although, in most cases, bighorn sheep avoid dense stands of Gambel oak [174]. Within north-central Utah, porcupines use Gambel oak as their primary winter food and cover source [190].
Acorns can also provide a food source for collared peccary in Arizona [115].
In the southern extent of its distribution, Gambel oak occupies a minor role as an
associate within ponderosa pine (Pinus ponderosa) and mixed-conifer habitats. Moving north,
long-lived Gambel oak clones form dominant to monotypic overstories [157].
Harper and others [92] constructed a list of common plant associates in a 1985 literature review. The following table lists common plant associates of Gambel oak.
Gambel oak is a typical riparian species in New Mexico, occurring from 6,580 to
8,080 feet (2,006 - 2,463 m) within the Black and Sacramento mountain ranges
[74].
Gambel oak is a dominant species in the central Utah mountain brush zone at 6,500 to 7,800 feet (1,981-2,377 m) on southern exposures. On northern exposures Gambel oak
either shares dominance with bigtooth maple (Acer grandidentatum) or
is completely replaced by bigtooth maple [36]. Bigtooth maple is a
common Gambel oak associate at the southern end of the Wasatch Mountains. On the west flank of the southern and middle Wasatch
range, Gambel oak and bigtooth maple form a dense woodland [91].
In Arizona Gambel oak is represented as shrub thickets over the majority of its range. It occurs as a tree throughout the ponderosa pine habitat type. The habit of Gambel oak within ponderosa pine-Gambel oak habitat types corresponds to the overall density of ponderosa pine. In dense ponderosa pine stands,
Gambel oak is sparse and short; stems are taller and clumped in open stands [144].
At an elevation range of 8,000 to 8,600 feet (2,440-2,620 m) in Arizona, Gambel oak is subdominant to ponderosa pine with southwestern white pine (Pinus
strobiformis) [20]. On heavier-textured soils in Colorado,
serviceberry (Amelanchier spp.) is an important associate [185].
Published classifications listing Gambel oak as an indicator or dominant are
listed below:
A classification of forest habitat types of the northern portion of the Cibola National Forest, New Mexico [3]
A classification of forest habitat types of the Lincoln National Forest, New Mexico [4]
Douglas-fir habitat types of northern Arizona [5]
Classification of the forest vegetation of Colorado by habitat type and community type [6]
Forest Vegetation on National Forests in the Rock Mountain and Intermountain
Regions: habitat and community types [7]
Forest vegetation of the Medicine Bow National Forest in southwestern Wyoming: a
habitat classification [8]
Classification of the forest vegetation on the National Forests of Arizona and New Mexico [9]
Climax forest series of northern New Mexico and southern Colorado [49]
Forest habitat types south of the Mogollon Rim, Arizona and New Mexico [50]
A classification of forest habitat types of northern new Mexico and southern Colorado [51]
Forest habitat types in the Apache, Gila and part of the Cibola National Forests, Arizona and New Mexico [70]
Grassland, shrubland and forestland habitat types of the White River-Arapaho National Forest [99]
Forest vegetation of the Routt National Forest in Northwestern Colorado: a habitat classification [103]
Forest vegetation of the Gunnison and parts of the Uncompahgre National Forests: a preliminary habitat type classification [117]
Forest and woodland habitat types (plant associations) of northern New Mexico and northern Arizona [129]
A classification of spruce-fir and mixed conifer habitat types of Arizona and New Mexico [146]
Aspen community types of Utah [148]
A classification of forest habitat types: southern Arizona and portions of the Colorado Plateau [149]
Plant associations (habitat types) of the forests and woodlands of Arizona and New Mexico [191]
A management-oriented classification of pinyon-juniper woodlands of the Great Basin [211]
Forest habitat types on the Medicine Bow National Forest, southeastern Wyoming: preliminary
report [215]
Coniferous forest habitat types of central and southern Utah [220]
Silviculture: Effective management of Gambel oak forests requires methods to assess current stand conditions
and predict changes in relation to treatments imposed.
Several studies provide evidence regarding Gambel oak's ability to suppress other plant species. Allelopathic toxins produced by Gambel oak may limit the natural regeneration
ability of ponderosa pine seedlings [95], but research results are limited. As an understory component of a ponderosa pine forest in central Arizona, Gambel oak did not limit the growth of overstory ponderosa pine [19]. Gambel
oak suppresses herbaceous species in open rangeland [106].
Density of Gambel oak stems within a stand is significantly (p < 0.05) related to stand height.
According to McKell [143] and Brown [26], young Gambel oak thickets are generally
dense, but thin out with age. Stand characteristics for Gambel oak between 6,890 and 8,200 feet
(2,100-2,500 m) receiving annual precipitation of 14 to 20 inches (360-510 mm) in Utah were evaluated. As stand height increased, stem
density decreased. A summary of stand characteristics is given below [38]:
Stand height is not directly related to age. Stands with stems up to 142 years old produced trees similar in height to stands 1/3rd to 2/3rds as old. The same study found that lignotubers compromised 72% of the total belowground biomass of Gambel oak [38].
In general, heavy logging of ponderosa pine favors Gambel oak
[170]. Clearcutting of a ponderosa pine overstory in a forest with a Gambel oak and alligator juniper understory was
evaluated 23 years later. Gambel oak stocking had increased 1.5 times, mostly in the form of vegetative sprouts, with regeneration averaging 1,090 ? 167 stems per acre. Clearcutting resulted in establishment of
a Gambel oak-brushfield in what was previously a ponderosa pine forest [95]. Gambel oak consistently sprouted adjacent
to slash windrows in a ponderosa pine clearcut in Arizona [193].
Chojnacky [31,32] provides volume equations for Gambel oak in Arizona. Hutchings and Lamar [104] provide equations to estimate Gambel oak yields from foliage cover and basal area on various range sites in Utah.
An evaluation of snag density and composition on
2 national forests in Arizona reported that Gambel oak contributed 18% of snags in ponderosa pine forests, with ponderosa pine contributing 76.4% (alligator juniper
was 2.3%). Within mixed-conifer forests Gambel oak contributed 24.3%, with white fir (Abies concolor) at 25.1%, ponderosa pine at 4.9%, and quaking aspen at 8.3% [78].
Inonotus andersoni is a fungus with the ability to girdle Gambel oak and kill the cambium. Although Inonotus
andersoni is a functional member of Gambel oak habitats, it does not pose a major threat. Decay is a slow process most often occurring in older trees and does not seriously affect regeneration. Wildlife habitat is created through fungal-induced snags and live trees with snag characteristics [66].
A rotational fuel wood harvest cycle of 65 years allows Gambel oak clones to grow
stems greater than the minimum fuel wood size of 3.5 inches (8.8 cm) in north-central Utah [207].
Soil ecology: Gambel oak places a heavy draw on soil moisture both within oak thickets and in open areas between oak thickets. Tew [195] observed soil moisture utilization by Gambel oak in
northern Utah. An oak stand of 65 square foot basal area/acre (6 m2/ha) used 11 to 13 inches
(28-33 cm) of water per year from the upper 8 feet (2 m) of soil. Initial water uptake occurs within the upper
4 feet (1.2 m) with additional water removed from the 4 to 8 foot (1-2 m) zone [195]. In northern Arizona Gambel oak was more effective at avoiding soil water stress and atmospheric water stress
than old- growth ponderosa pine [116]. A comparison of mean soil moisture content (%) among 4 Gambel oak rangeland sites in southwestern Colorado was conducted over the course of 3 years. Results show higher soil moisture content (%) within herbicide controlled oak rangelands [138]:
Leaf litter produced by Gambel oak has a
positive effect on soil nitrogen within the surface (upper 5.9 inches (15 cm) of soil) [113,114]. Gambel oak
leaves contain 2 to 4 times the N, P, S, Ca, Mg, and K of pine needles. Leaves also contain 8% less C than ponderosa pine needles. Gambel oak enhances nutrient release of ground cover within ponderosa pine stands by decaying faster than
ponderosa pine litter. Presence of oak leaf litter may alter the distribution of nutrients within ponderosa pine forest floors [113].
The C:N ratio in ponderosa pine forest litter decreases when Gambel oak is a member of the understory compared to
ponderosa pine without Gambel oak [131]. A comparison of nutrients between freshly fallen
Gambel oak leaves and ponderosa pine needles from trees growing side by side shows significantly higher nutrient content in Gambel oak litter [114]:
Grazing: Beef production per acre is much greater in Gambel oak-controlled pastures than in pastures with no Gambel oak control. In southwestern Colorado herbicides have been used to decrease Gambel oak and increase livestock productivity [138]. In general, cattle are safe from poisoning if other forage is available. Cattle should not be released when hungry on Gambel oak ranges with little forage other than oak [189].
Jefferies [106] found greater herbage production of needle-and-thread (Hesperostipa comata), western wheatgrass (Pascopyrum smithii), and blue grama (Bouteloua gracilis) in openings between oak stands than under Gambel oak canopies in both grazed and protected pastures. Kentucky bluegrass (Poa pratensis) had greater production under canopy than in the open [106]. Seeding of Gambel oak rangeland in Utah should occur in the fall, just before leaf fall. Stevens and Davis [187] recommend aerial seeding followed with mechanical disturbance. Further information including a summary of recommended species, depending upon community type, is found in Stevens and Davis
[187].
Gambel oak is most susceptible to insect herbivory early in the growing season, with young expanding leaves preferred [65]. Gambel oak leaves support a higher insect biomass per
unit of foliage than ponderosa pine [37].
Control methods: Top-kill
of Gambel oak promotes vegetative sprouting. Numerous studies document the sprouting ability of Gambel oak after mechanical crushing [59] or herbicide treatment
[59,92,98,139]. In general, the best strategy for reducing vigor of sprouting species is to apply control methods during periods of low carbohydrate reserves [16]. However, total eradication of Gambel oak is rare due to prolific vegetative regeneration from roots, rhizomes and basal stems [59]. Most
control options provide short-term benefits that eventually produce Gambel oak thickets [130].
Control of Gambel oak with herbicides is extremely variable
depending upon growing season and herbicide used. Herbicides may induce prolific sprouting, producing rangelands of lower
quality than the original stand [139]. The herbicide application rates of
picloram, 2,4-D, or 2,4,5-T necessary to control Gambel oak kill most desirable shrubs and forbs. Fenuron kills Gambel oak but is persistent, producing a soil sterilization effect and a subsequent elimination of desirable plants [205]. Effective control can be obtained from a mixture of
picloram and 2,4,5-TP [139]. Picloram pellets are an ineffective control for Gambel oak [45,46].
Application of hormone-type herbicides is recommended before full leaf stage or in late August before the end of fall regrowth corresponding to downward translocation. August applications, however, may be less effective due to wax accumulations on existing mature leaves [60]. Applications corresponding with downward assimilate translocation maximize herbicide concentrations in the underground parts, where effective plant damage occurs [151].
Lauver and others [130] suggest integrated management for optimum control of Gambel oak. High application rates and high treatment costs are usually required for herbicide control of Gambel oak [204]. Thinning programs, when conducted correctly, promote growth of remaining Gambel oak stems (not resprouts) allowing forage increases [130].
Combined with other nutritious forage low in tannin content, Gambel oak provides a healthy diet for domestic goats [152]. When domestic goat browsing was initiated in late spring with periods of high intensity short duration grazing throughout the growing season in Northern Utah, Gambel oak
showed a 78% reduction after 2
successive years [172].
When Gambel oak is abundant, domestic goats may prefer it to other available browse. Davis and others [47] provide several management considerations for obtaining maximum oak control from goats: all oak brush foliage should be accessible; time of goat browsing should center around late June (full leaf stage) and August (late summer regrowth); stocking rates of 5 to 10 goats per acre are preferred [47].
Wildlife: Kufeld [122] recommends fall prescribed burns rather
than chaining or spraying to manage Gambel oak brush rangelands for elk, deer and cattle.
Domestic goats were found to reduce the amount of Gambel oak browse available to wintering deer
in Utah. Deer responded with greater consumption of sagebrush (Artemisia spp.) and
rabbitbrush (Chrysothamnus spp.) [173]. A detailed description of the management of
Gambel oak associations for wildlife and livestock was prepared by Steinhoff [185].
Mature and juvenile Gambel oaks provide valuable forage with nitrogen and energy in excess of
maintenance requirements for Spanish goats [52]. At 5.4% crude protein, Gambel oak does not meet the protein requirement of wintering mule deer [208]. Protein content of
Gambel oak leaves was found to decrease starting June to September while phosphorus and gross energy
remained constant [47]. As winter browse, Gambel oak is low in essential nutrients [182], with crude protein less
than 10% [198].
The percent nutrient content of Gambel oak during January from 9 geographic areas throughout Colorado is summarized below [123]:
Dick and others [52] compared chemical composition of juvenile and mature Gambel oak:
Buds
9.5 ? 0.36
0.17 34.0 ? 0.59Twigs
7.5 ? 0.22 0.13 29.8 ? 0.70Native Americans of the Southwest used Gambel oak acorns for food [29].
Gambel oak may contribute up to 50% of diet without cattle showing any ill effects. Poisoning occurs when more than 50% is consumed, with death often resulting when more than 75% of cattle's diet is Gambel oak [26]. Freezing enhances toxic properties of Gambel oak browse; young foliage turned black by freezing is extremely toxic [189].
The palatability of Gambel oak to livestock and wildlife species in several western states has been rated as follows [55] :
Gambel oak flowers usually appear in late March to early April with acorns ripening in August or September [92]. In Utah, flowers appear when leaves are nearly half grown, usually May or June [13]; at the lower elevation limits in Utah, flowers occasionally appear in early May [28,200]. Acorns mature in northern Utah from September to early October [35]. The following table provides a summary of Gambel oak seasonal development during a 160 to 175 day growing season at 7,655 feet (2,333 m) in northern Utah [42]:
Flower buds bursting Leaf buds bursting In full leaf In full bloom Fruit ripe Fruit dropped May 25 May 23 June 17 June 5 September 25 October 10Gambel oak produces buds in winter for the following spring. Not all buds produced in winter become active; some dormancy is maintained. Dormant buds may become active if new shoots are defoliated [59].
In southwestern Colorado, at least 5 weeks are required after snowmelt before onset of spring growth. Photoperiod requirements prevent bud burst occurring earlier than the 3rd week of May. Shoot elongation is generally 24 to 27 days and is not dependent upon date of bud burst [192].
Fire usually stimulates sprouting of Gambel oak after top-kill [13,26,53,76,143], increasing density of previously open stands and merging scattered stands into continuous thickets [26]. Gambel oak regeneration after fire is usually vigorous [143]. Sprouts may be observed within 10 postfire days [198].
Seed: Caches of acorns gathered by rodents are a source of postfire regeneration [158].
Sprouting: First-year responses to fire show vigorous Gambel oak regrowth. Adventitious buds located on rhizomes and lignotubers may produce stems reaching up to 18 inches (45.7 cm) in height. Surviving stems also resprout from buds [144]. Dormant buds on rhizomes are stimulated by fire [143]. Rhizomes generally lie between 4 and 20 inches (10-50 cm) below soil surface, so they are protected from all but the most severe fires [198]. Wright [217] predicts continued growth after fire in Gambel oak, inducing a natural thinning of continuous thickets that ultimately decline to coverage equaling the previously unburned stand within 18 years.
Tree with adventitious bud/root crown/soboliferous species root sucker
Tall shrub, adventitious bud/root crown
Secondary colonizer (on-site or off-site seed sources)
Gambel oak reproduces by seed and vegetatively [6,92].
Seed: Production of mature flowers is directly related to moisture availability. Xeric sites often fail to produce mature female flowers, yet male catkins are produced in abundance. On moist sites, flowers of both sexes are produced in large numbers [75]. Acorn production in Arizona was directly related to moisture availability, averaging 188,000 mature acorns/acre (464,548/ha) and over 331,000 per acre (817,900/ha) in heavy moisture years [142]. Although Gambel oak generally possesses distinct male and female inflorescences on a single plant, Tucker and others [200] observed an inflorescence containing both anthers and pistils in Utah. The following year strictly monoecious flowers were produced. Female flowers are found throughout the Gambel oak canopy while male flowers are almost exclusively located at the top [75].
Extent of acorn production is also related to stem diameter. Few acorns are produced from stems less than 2 inches (5.1 cm) diameter breast height (d.b.h.), and production rapidly declines when stems are greater than 14 inches (35.6 cm). Maximum acorn production occurs from stems 12 to 14 inches (30.5-35.6 cm) d.b.h. [142,171]. Throughout Utah, 4 to 6 months are required to produce mature acorns [42,92]. Spring freezing may reduce acorn production [156].
Gambel oak may occur at high elevations, where a 60- to 90-day growing season exists. Although at high-elevation ranges the growing season is too short to produce mature acorns, expansion occurs through vegetative reproduction [92]. Limited colonization of the higher-elevational range is thought to be a function of the short growing season [35].
Overall effectiveness of reproduction through seed is directly related to moisture availability [219]. Seedlings are more common in the southern range of Gambel oak [157], where summer rains are heavy and more frequent [155]. Fewer seedlings are found in the northern range [150,155,157]. Neilson [157] found seedling establishment directly relating to consistently high presence of soil moisture. Persistent mesic conditions provide the best conditions for seedling survival. Greater survivorship in winter and summer is also associated with closed canopies [219].
Colonization through seed is enhanced by avian and small mammal acorn dispersal. Acorns of Gambel oak are dispersed by rodents and birds [6]. Band-tailed pigeons, scrub jays, Steller's jays, Lewis woodpeckers, and acorn woodpeckers are agents of dispersal [33,91,92]. The Utah rock squirrel regularly provides short-distance acorn dispersal [167].
Vegetative: Gambel oak has strong vegetative reproduction capabilities. In most of its range, Gambel oak regeneration depends more on sprouting than establishment from seed [128]. The large underground structure of Gambel oak supports rapid and extensive sprouting following top removal [38]. In Utah vegetative spread of Gambel oak thickets averaged 4-inches (10 cm) per year, with lows of 1.5 inches (3.8 cm) and a high of 12 inches (30.5 cm) [92]. Vegetative reproduction occurs through adventitious buds on lignotubers [198] and freely branched rhizomes [150]. A large difference in ability to regenerate by cloning exists between the southern and northern range of Gambel oak. In Arizona and New Mexico, groupings usually consisted of 1 to 7 ramets per clone [157] compared to 100 to 1,000 ramets per clone observed in the north [26,169].
The distribution of adventitious buds and rhizomes (in cm) within the soil profile of a Gambel oak stand in central Utah was as follows [198]:
Unit surface-10 10-20 20-30 30-40 40-50 50 + Adventitious buds Number 1293 4325 1978 727 671 133 % 14 48 22 8 7 1 Rhizomes Number 0 7 2 7 6 1Adventitious buds were concentrated in the top 11.8 inches (30 cm) of soil. More adventitious buds were found on lignotubers than on rhizomes [198]. Lignotubers provide the primary source for regeneration after top-kill; rhizomes possess fewer buds and facilitate widespread development of clones [108].
6 Upper Basin and Range
7 Lower Basin and Range
11 Southern Rocky Mountains
12 Colorado Plateau
Canopy suppression is a successional trend when Gambel oak is associated with bigtooth maple, white fir, ponderosa pine, Rocky Mountain juniper, or Colorado pinyon [34,36,56,71,96,143,159]. Across its range, Gambel oak occupies a seral, postfire successional stage with late successional associates more susceptible to fire [22,62,214].
Gambel oak is listed as a persistent seral stage in the ponderosa pine of northern Arizona, with he majority of Gambel oak occurring as trees. Populations of Gambel oak increase with disturbance in ponderosa pine woodlands [90].
In southern and southwestern Colorado, Gambel oak occupies a secondary successional stage in ponderosa pine and Douglas-fir (Pseudotsuga menziesii) stands removed by fire or logging [26,93]. It is a persistent subclimax to conifers or a climax species of foothill ranges [56,59,96,134].
Mountain brush vegetation where Gambel oak and bigtooth maple are codominant tend to develop into a bigtooth maple-dominated brush type. The successional transition to a bigtooth maple dominant overstory is attributed to the greater reproductive potential and shade tolerance of bigtooth maple [159]. Within Gambel oak-bigtooth maple brush, bigtooth maple seedlings grow readily under and on the periphery of bigtooth maple and Gambel oak canopies. Gambel oak seedlings are rarely observed under dense bigtooth maple canopies [36]. Bigtooth maple successfully invaded Gambel oak brush in the Wasatch Mountains of Utah, while Gambel oak had difficulty invading bigtooth maple stands [159].
In central Utah, Gambel oak/bigtooth maple brush communities at 6,500 to 7,800 feet (1,981-2,377 m) may succeed to conifer-pinyon-juniper at the low elevations and to white fir at upper elevations [134].
The scientific name of Gambel oak is Quercus gambelii Nutt. (Fagaceae) [127,210]. Varieties include [203]:
Quercus gambelii Nutt. var. bonina S.L. Welsh, Goodhope oak
Quercus gambelii Nutt. var. gambelii, Gambel oak
Hybridization between oak species is common. Gambel oak
hybridizes readily with other oak species and has influenced the
evolution of several oaks [92]. Hybridization occurs with Arizona white oak (Q. arizonica) [201], bur oak (Q. macrocarpa) [30,201], chinkapin oak (Q. muehlenbergii), gray oak (Q. grisea) [2,84,201], Mohr's oak (Q. mohriana) [201], and shrub live oak (Q. turbinella)
[43,201].
Gambel oak has not been used extensively for environmental rehabilitation of disturbed sites. The majority of research has been centered toward control or eradication. However, Gambel oak has a moderate value for long-term revegetation. The extensive root system helps provide soil stability and reduce erosion [33].
Propagation of Gambel oak using stem cuttings has shown little success [92,179]. Sopp [184] recommends stratification of Gambel oak seeds for 2 weeks at 35.6 degrees Fahrenheit (2 o C) to obtain maximum germination results. Sopp also recommends disinfecting acorns to prevent contamination by pathogens.
Gambel oak is a good source of fuel wood. Within the Intermountain Region, productivity is high enough to exceed economic thresholds, and profuse vegetative regeneration is ideal for a fuel wood management cycle [107].
Gambel oak is a good source of firewood that produces little smoke and soot. An average weight per standard cord, based upon 80 cubic feet of solid wood in pounds, is summarized below [14]:
Oven Dry Air-dry (12% moisture) Green (65% moisture) 3168 3548 5227It takes 9 months to 1 year to air dry green Gambel oak [14]. Gambel oak provides more energy than other common southwestern trees [92,214]:
52 % more than quaking aspen (Populus tremuloides)
42 % more than ponderosa pine
36 % more than lodgepole pine (Pinus contorta)
24 % more than Rocky Mountain juniper (Juniperus scopulorum)
Gambel oak was compared with Colorado pinyon (Pinus edulis), alligator juniper (Juniperus deppeana), ponderosa pine and eastern redcedar (Juniperus virginiana) for specific wood product values. An average comparative index based upon a weighted combination of specific strength values is summarized below [14]. Final index values were obtained at 20% moisture content.
Property Gambel oak Colorado pinyon alligator juniper ponderosa pine eastern redcedar Bending strength 70 60 63 65 67 Comprehensive strength 67 75 76 69 87 Stiffness 78 108 60 112 80 Hardness 137 73 107 41 81 Shock resistance 78 65 79 58 114 Volumetric shrinkage 121 99 73 97 78Small-diameter stems of Gambel oak that are reasonably straight make ideal fenceposts that are decay-resistant and more durable than other oaks [14]. Untreated posts outlast both Emory oak (Quercus emoryi) and Arizona white oak [133].
Quercus gambelii (lat. Quercus gambelii) - fıstıqkimilər fəsiləsinin palıd cinsinə aid bitki növü.
Palıd cinsinə aid növlər Q. grisea• Q. oblongifolia• Q. acerifolia• Q. acuta• Q. acutissima• Q. afares• Q. agrifolia• Q. alba• Q. albocinta• Q. aliena• Q. alnifolia• Q. arizonica• Q. arkansana• Q. aucheri• Q. austrina• Q. basaseachicensis• Q. benthamii• Q. berberidifolia• Q. bicolor• Q. boyntonii• Q. brandegeei• Q. brenesii• Q. breviloba• Q. buckleyi• Q. bumelioides• Q. calliprinos• Q. canariensis• Q. castaneifolia• Q. cedrosensis• Q. cerrioides• Q. cerris• Q. chapmanii• Q. chrysolepis• Q. coahuilensis• Q. coccifera• Q. coccinea• Q. convallata• Q. conzattii• Q. copeyensis• Q. cornelius-mulleri• Q. corrugata• Q. costaricensis• Q. cubana• Q. deliquescens• Q. dentata• Q. depressa• Q. depressipes• Q. devia• Q. diversifolia• Q. douglasii• Q. dumosa• Q. durata• Q. ellipsoidalis• Q. emoryi• Q. engelmannii• Q. excelsa• Q. faginea• Q. falcata• Q. flagellifera• Q. frainetto• Q. fulva• Q. fusiformis• Q. galeanensis• Q. gambelii• Q. garryana• Q. georgiana• Q. germana• Q. glauca• Q. glaucoides• Q. graciliformis• Q. gravesii• Q. gulielmitreleasei• Q. havardii• Q. hemisphaerica• Q. hintonii• Q. hintoniorum• Q. humboldtii• Q. hypoxantha• Q. iberica• Q. ilex• Q. ilicifolia• Q. imbricaria• Q. invaginata• Q. john-tuckeri• Q. kelloggii• Q. laceyi• Q. laevis• Q. lamellosa• Q. laurifolia• Q. libani• Q. liebmannii• Q. lobata• Q. lusitanica• Q. lyrata• Q. macdonaldii• Q. macdougallii• Q. macranthera• Q. macrocarpa• Q. macrolepis• Q. marilandica• Q. martinezii• Q. michauxii• Q. miquihuanensis• Q. mohriana• Q. mongolica• Q. muehlenbergii• Q. myrsinifolia• Q. nigra• Q. oglethorpensis• Q. oleoides• Q. pacifica• Q. pagoda• Q. palmeri• Q. palustris• Q. peninsularis• Q. perpallida• Q. petraea• Q. phellos• Q. planipocula• Q. polymorpha• Q. pontica• Q. praeco• Q. praineana• Q. prinoides• Q. prinus• Q. pubescens• Q. pungens• Q. purulhana• Q. rapurahuensis• Q. robur• Q. robusta• Q. rubra• Q. rugosa• Q. rysophylla• Q. sadleriana• Q. sebifera• Q. shumardii• Q. skinneri• Q. skutchii• Q. stellata• Q. suber• Q. subspathulata• Q. tardifolia• Q. texana• Q. tomentella• Q. tonduzii• Q. toumeyi• Q. trojana• Q. turbinella• Q. undata• Q. uxoris• Q. vacciniifolia• Q. variabilis• Q. velutina• Q. vincentensis• Q. wislizeni• Q. xalapensis• Q. zempoaltepecana• Q. × alvordiana 
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Quercus gambelii (lat. Quercus gambelii) - fıstıqkimilər fəsiləsinin palıd cinsinə aid bitki növü.
Quercus gambelii, o el roure de Gambel, és un arbre petit caducifoli o arbust gran generalitzada als turons i baixes elevacions muntanyoses del centre sud-oest dels Estats Units i del nord-oest de Mèxic: la seva àrea de distribució se centra en l'altiplà de Colorado - Four Corners ("Quatre Cantonades") dels estats de Utah, Colorado, Arizona, Nou Mèxic, sinó que la seva àrea de distribució va a Nevada, Wyoming, Dakota del Sud, Kansas, Oklahoma i l'oest de Texas.[1][2] A Mèxic sobretot al nord de Sonora-Chihuahua. En general creix a una altitud de 1.000-3.000 metres sobre el nivell del mar, on les mitjanes de precipitació estan entre 30-60 centilitres per any.
El roure de Gambel varia significativament en grandària d'un lloc a un altre. L'alçada mitjana en estat adult és de 3 a 9 metres, però de vegades aconsegueix altures de 18 metres en alguns indrets. Són freqüents en les zones marginals la forma nana, quan es troba per sota d'un metre d'alçada on les pastures són pobres. L'arbre es reprodueix a partir de glans, però es propaga més ràpid a través de brots d'arrel que creixen d'estructures subterrànies vastes anomenats lingotúbers. Aquestes característiques reproductives sovint ocasionen boscos densos o matollars que sovint cobreixen totes les vessants muntanyenques.
Malgrat que la fusta d'aquest tipus de roure és dura i densa, les seves branques són irregulars i tortes, per la qual cosa són prou flexibles per doblegar sense trencar-les quan estan cobertes de neu. L'escorça és aspra i de color marró gris. Les fulles són generalment 7-12 cm de llarg i d'ample 4-6 cm, profundament lobulades en cada costat de la vena central, la superfície de la part superior és de color verd fosc brillant, la superfície de la part inferior és més pàl·lida i vellutada. Sovint es tornen de color taronja i groc a la tardor, creant muntanyes de colors vius. Les flors són aments discrets unisexuals que es produeixen a la primavera. Les glans fan d'1-2 centímetres de llarg, i al voltant d'un terç a la meitat tancada per una tapa o una cassoleta (cúpula), i maduren al setembre, convertint-se de verd en marró daurat.
El roure de Gambel floreix a ple sol en les vessants amb sòl bàsic, rocós, alcalí; on la competència d'unes altres espècies vegetals és limitada. També li va bé en sòls més rics, però en aquelles zones es veuen obligats a competir per a espai de creixement. S'adapta bé als llocs on els brolladors humits i estius càlids i secs creen les condicions propícies per als incendis forestals. Després d'un incendi, el roure de Gambel ràpidament es restableix a partir de brocs d'arrel. Aquest tipus de roure és força tolerant a la sequera.
A causa de la seva abundància, el roure de Gambel és una important font alimentària per a animals de pas com el cérvol i el bestiar. Els esquirols recullen de forma regular les glans i les emmagatzemen al seu cau i tenir així una provisió de menjar a l'hivern. Alguns insectes depenen de roure de Gambel; per exemple, la papallona de Colorado l'utilitza com a font alimentària per a erugues. Històricament, les glans del roure de Gambel proporcionaven una font solvent de menjar per als Nadius americans.
Les espècies vegetals associades inclouen cirerer de Virgínia, Balsamorhiza sagittata, Acer grandidentatum, cercocarpus, pi Ponderosa i amelanchier. Els ocells associats i els mamífers inclouen Aphelocoma californica, Garsa de bec negre, tetraònid, cérvol, esquirol llistat i esquirols.
El roure de Gambel té aquest nom per al naturalista nord-americà William Gambel (1823–;1849).
Quercus gambelii, o el roure de Gambel, és un arbre petit caducifoli o arbust gran generalitzada als turons i baixes elevacions muntanyoses del centre sud-oest dels Estats Units i del nord-oest de Mèxic: la seva àrea de distribució se centra en l'altiplà de Colorado - Four Corners ("Quatre Cantonades") dels estats de Utah, Colorado, Arizona, Nou Mèxic, sinó que la seva àrea de distribució va a Nevada, Wyoming, Dakota del Sud, Kansas, Oklahoma i l'oest de Texas. A Mèxic sobretot al nord de Sonora-Chihuahua. En general creix a una altitud de 1.000-3.000 metres sobre el nivell del mar, on les mitjanes de precipitació estan entre 30-60 centilitres per any.
El roure de Gambel varia significativament en grandària d'un lloc a un altre. L'alçada mitjana en estat adult és de 3 a 9 metres, però de vegades aconsegueix altures de 18 metres en alguns indrets. Són freqüents en les zones marginals la forma nana, quan es troba per sota d'un metre d'alçada on les pastures són pobres. L'arbre es reprodueix a partir de glans, però es propaga més ràpid a través de brots d'arrel que creixen d'estructures subterrànies vastes anomenats lingotúbers. Aquestes característiques reproductives sovint ocasionen boscos densos o matollars que sovint cobreixen totes les vessants muntanyenques.
Malgrat que la fusta d'aquest tipus de roure és dura i densa, les seves branques són irregulars i tortes, per la qual cosa són prou flexibles per doblegar sense trencar-les quan estan cobertes de neu. L'escorça és aspra i de color marró gris. Les fulles són generalment 7-12 cm de llarg i d'ample 4-6 cm, profundament lobulades en cada costat de la vena central, la superfície de la part superior és de color verd fosc brillant, la superfície de la part inferior és més pàl·lida i vellutada. Sovint es tornen de color taronja i groc a la tardor, creant muntanyes de colors vius. Les flors són aments discrets unisexuals que es produeixen a la primavera. Les glans fan d'1-2 centímetres de llarg, i al voltant d'un terç a la meitat tancada per una tapa o una cassoleta (cúpula), i maduren al setembre, convertint-se de verd en marró daurat.
Quercus gambelii, with the common name Gambel oak, is a deciduous small tree or large shrub that is widespread in the foothills and lower mountains of western North America. It is also regionally called scrub oak, oak brush, and white oak.[3][4]
The common and scientific names, Gambel oak and Quercus gambelii, were named after the American naturalist William Gambel (1821–1849).[5]
Quercus gambelii trees differ in size from one location to another. The average mature height is from 3–9 metres (10–30 feet), but occasionally reaches heights of 18 m (59 ft) in some locations. Dwarf stands of plants under 1 m (3+1⁄4 ft) tall are common in marginal areas where heavy browsing occurs.[3] The largest trees are found in the southern range of the species along streams. These trees reach up to 100 feet tall. The champion tree is in Arizona at 35 m (114 ft) tall. [6]
Although the wood is hard and dense, its branches are irregular and crooked, making them flexible enough to bend without breaking when covered with heavy snow. The bark is rough and brownish-gray.
The leaves are generally 7–12 centimetres (3–4+1⁄2 inches) long and 4–6 cm (1+1⁄2–2+1⁄2 in) broad, deeply lobed on each side of the central vein; the upper surface is glossy dark green, the undersurface is paler and velvety. Leaves frequently turn orange and yellow during autumn, creating mountainsides of vivid colors. The flowers are inconspicuous unisexual catkins that occur in the spring.[3]
The acorns are 10–20 millimetres (3⁄8–3⁄4 in) long and about one-third to one-half enclosed by a cap or cup (cupule); they mature in September, turning from green to golden brown. The plant reproduces from acorns, but also spreads from root sprouts that grow from vast underground structures called lignotubers. These reproductive characteristics often result in dense groves or thickets of trees that can cover entire mountainsides.[3]
The natural range of Quercus gambelii is centered in the western United States and northwestern Mexico in the states of Arizona, Chihuahua, Colorado, New Mexico, Sonora, and Utah. It also extends into Nevada, Wyoming, Idaho, Nebraska, the Oklahoma Panhandle, Coahuila, and into the Trans-Pecos region of western Texas.[3][4][7][8][9]
The tree typically grows at altitudes of 1,000–3,000 m (3,300–9,800 ft) above sea level where precipitation averages between 30–60 cm (12–24 in) per year.
The species flourishes in full sun on hillsides with thin, rocky, alkaline soil where competition from other plant species is limited. It also does well in richer soils, but in those areas it is forced to compete for growing room. It is well-adapted to locations where wet springs and hot, dry summers create conditions conducive to wildfires.
After a fire, Gambel oak quickly re-establishes from root sprouts. The plant is drought tolerant.
Associated plant species include: chokecherry, arrowleaf balsamroot, bigtooth maple, mountain mahogany, ponderosa pine, and serviceberry. Associated birds and mammals include Woodhouse's scrub jay, black-billed magpie, grouse, deer, chipmunks and squirrels.
Where abundant, Gambel oak is an important food source for browsing animals such as deer and livestock.[5] The sweetish acorns are frequently gathered by squirrels and stored for winter food. Acorns are also eaten by wild turkeys, black bears, and domestic animals such as hogs.[5][10] Some insects depend on the Gambel oak: for example, the Colorado hairstreak butterfly uses it as a food source for caterpillars.
Historically, acorns from Gambel oak provided a reliable source of food for Native Americans.[11] If bitter, tannins can be leached[12] from the acorns.
Quercus gambelii, with the common name Gambel oak, is a deciduous small tree or large shrub that is widespread in the foothills and lower mountains of western North America. It is also regionally called scrub oak, oak brush, and white oak.
The common and scientific names, Gambel oak and Quercus gambelii, were named after the American naturalist William Gambel (1821–1849).
Quercus gambelii es una especie de roble de la familia Fagaceae que es originaria de América del Norte. 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 seis 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.[1][2]
Es un árbol pequeño caducifolio o arbusto grande que se distribuye por las colinas y bajas elevaciones montañosas del centro suroeste de los Estados Unidos y del noroeste de México: su área de distribución se centra en la meseta de Colorado - Four Corners ("Cuatro Esquinas") de los estados de Utah, Colorado, Arizona, Nuevo México; además su área de distribución va hasta Nevada, Wyoming, Dakota del Sur, Kansas, Oklahoma y el oeste de Texas.[1][3] En México en todo el norte de Sonora-Chihuahua. En general crece a una altitud de 1000-3000 metros sobre el nivel del mar, donde los promedios de precipitación están entre 30-60 centilitros por año.
El roble de Gambel varía significativamente en tamaño de un lugar a otro. La altura media en estado adulto es de 3 a 9 metros, pero a veces alcanza alturas de 18 metros en algunos lugares. Son frecuentes en las zonas marginales la forma enana, cuando se encuentra por debajo de un metro de altura donde los pastos son pobres. El árbol se reproduce a partir de bellotas, pero se propaga más rápido a través de brotes de raíz que crecen de estructuras subterráneas vastas llamados lignotúberes. Estas características reproductivas a menudo ocasionan bosques densos o matorrales que a menudo cubren todas las vertientes montañosas.
Aunque la madera de este tipo de roble es dura y densa, sus ramas son irregulares y torcidas, por lo que son lo suficientemente flexibles para doblarse sin romperse cuando están cubiertas de nieve. La corteza es áspera y de color marrón gris. Las hojas son generalmente de 7-12 cm de largo y de ancho 4-6 cm, profundamente lobuladas en cada lado de la vena central, la superficie de la parte superior es de color verde oscuro brillante, la superficie de la parte inferior es más pálida y aterciopelada. A menudo se vuelven de color naranja y amarillo en otoño, creando montañas de colores vivos. Las flores son amentos discretos unisexuales que se producen en primavera. Las bellotas miden de 1-2 centímetros de largo, y alrededor de un tercio a la mitad cerrada por una tapa o una cazoleta (cúpula), y maduran en septiembre, convirtiéndose de verde en marrón dorado.
El roble de Gambel florece a pleno sol en las laderas con suelo básico, rocoso, alcalino; donde la competencia de otras especies vegetales es limitada. También le va bien en suelos más ricos, pero en aquellas zonas se ven obligados a competir por espacio de crecimiento. Se adapta bien a los lugares donde los manantiales húmedos y veranos cálidos y secos crean las condiciones propicias para los incendios forestales. Después de un incendio, el roble de Gambel rápidamente se restablece a partir de boquillas de raíz. Este tipo de roble es bastante tolerante a la sequía.
Debido a su abundancia, el roble de Gambel es una importante fuente alimenticia para animales de paso como el ciervo y el ganado. Las ardillas recogen de forma regular las bellotas y las almacenan en su madriguera y tienen así una provisión de comida en invierno. Algunos insectos dependen del roble de Gambel; por ejemplo, la mariposa de Colorado lo utiliza como fuente alimenticia para las orugas. Históricamente, las bellotas del roble de Gambel proporcionaban una fuente solvente de comida para los Nativos americanos.
Las especies vegetales asociadas incluyen el cerezo de Virginia, Balsamorhiza sagittata, Acer grandidentatum, Cercocarpus, Pinus ponderosa y Amelanchier. Los pájaros asociados y los mamíferos incluyen a: Aphelocoma californica, la Garza de pico negro, tetraoninos, ciervos y ardillas.
Quercus gambelii fue descrita por Thomas Nuttall y publicado en Journal of the Academy of Natural Sciences of Philadelphia 1(2): 179. 1848.[4]
Quercus: nombre genérico del latín que designaba igualmente al roble y a la encina.
gambelii: epíteto otorgado en honor del naturalista estadounidense William Gambel (1823-1849).
Quercus gambelii es una especie de roble de la familia Fagaceae que es originaria de América del Norte. 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 seis 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.
Quercus gambelii est un petit chêne caduc présent à l’état naturel en Amérique du Nord. Aux États-Unis, l’arbre porte le nom de Gambel oak et son nom latin provient du botaniste américain William Gambel (1823-1849).
L’arbre est présent dans des régions élevées du sud-ouest des États-Unis et du nord-ouest du Mexique à des altitudes de 1000 à 3 000 m. Les régions ont des précipitations annuelles comprises entre 300 et 600 mm.
Cette espèce de chêne apprécie les zones exposées au soleil où le sol calcaire peu profond est composé de roches et où la compétition avec d’autres arbres est limitée. Il apprécie également les sols plus riches mais il doit alors faire face à d’autres concurrents. Il est adapté pour les régions qui ont des printemps humides et des étés secs et chauds. Ces régions sont parfois en proie à des incendies et le chêne se remet rapidement des dégâts en repartant de ses racines. L’arbre est une source très importante de nourriture pour plusieurs espèces d’animaux. Les glands sont cachés par les écureuils pour mieux passer l’hiver. Le papillon Hypaurotis crysalus dépend de l’arbre car ses chenilles se nourrissent uniquement de ses feuilles. Les Amérindiens de ces régions se nourrissaient également des glands de ce chêne.
La taille de l’arbre varie fortement en fonction de sa localisation. Sa hauteur varie en moyenne entre 3 et 9 mètres mais atteint occasionnellement 18 mètres. Dans des régions très difficiles, l’arbre ne dépasse par un mètre de haut et possède une forme arbustive. L’arbre se propage grâce à ses glands mais également grâce à ses racines. Son bois est très dur et ses branches ont des formes irrégulières. Celles-ci sont suffisamment flexibles pour supporter le poids de la neige durant les hivers. Les feuilles mesurent de 7 à 12 centimètres pour 4 à 6 cm de large. Elles sont profondément lobées et possède une nervure centrale. La partie supérieure est vert foncé alors que le côté inférieur est plus clair. Elles deviennent jaunes ou orange en automne tout en décorant les paysages des montagnes environnantes. Les glands mesurent 1 à 2 centimètres et sont englobés sur le tiers ou la moitié de leur longueur dans une cupule. Verts au départ, ils deviennent bruns en automne.
Quercus gambelii est un petit chêne caduc présent à l’état naturel en Amérique du Nord. Aux États-Unis, l’arbre porte le nom de Gambel oak et son nom latin provient du botaniste américain William Gambel (1823-1849).
La quercia di Gambel (Quercus gambelii Nutt.) è una pianta della famiglia delle Fagaceae che cresce negli Stati Uniti d'America sud-occidentali e nel Messico nord-occidentale.[1]
Foglie e frutti
Corteccia
La quercia di Gambel (Quercus gambelii Nutt.) è una pianta della famiglia delle Fagaceae che cresce negli Stati Uniti d'America sud-occidentali e nel Messico nord-occidentale.
Multimedia w Wikimedia Commons Quercus gambelii Nutt. – gatunek roślin z rodziny bukowatych (Fagaceae Dumort.). Występuje naturalnie w północnym Meksyku (w stanach Chihuahua, Coahuila i Sonora) oraz środkowo-zachodnich Stanach Zjednoczonych (w Dakocie Południowej, Wyoming, Nevadzie, Utah, Kolorado, Arizonie, Nowym Meksyku, Oklahomie i Teksasie)[3][4][5].
Rośnie w lasach mieszanych. Występuje na wysokości od 1000 do 3000 m n.p.m.[5]
Niektóre plemiona Indian używały tego gatunku w medycynie tradycyjnej oraz w ceremonii szamańskich[5].
Quercus gambelii Nutt. – gatunek roślin z rodziny bukowatych (Fagaceae Dumort.). Występuje naturalnie w północnym Meksyku (w stanach Chihuahua, Coahuila i Sonora) oraz środkowo-zachodnich Stanach Zjednoczonych (w Dakocie Południowej, Wyoming, Nevadzie, Utah, Kolorado, Arizonie, Nowym Meksyku, Oklahomie i Teksasie).
Quercus gambelii là một loài thực vật có hoa trong họ Cử. Loài này được Nutt. miêu tả khoa học đầu tiên năm 1847.[1]
Quercus gambelii là một loài thực vật có hoa trong họ Cử. Loài này được Nutt. miêu tả khoa học đầu tiên năm 1847.
Quercus gambelii Nutt., 1847
Ареал
Дуб Гамбела[2][3][4], или Гэмбела[5] (лат. Quercus gambelii) — небольшое листопадное дерево или крупный кустарник, широко распространённый в предгорьях и невысоких горных возвышенностях Северной Америки.
Описан Томасом Наттоллом в 1848 году. Видовое название растению было дано в честь американского натуралиста Уильяма Гэмбела (англ. William Gambel, 1823—1849).
Ареал Quercus gambelii охватывает запад США и северо-запад Мексики, главным образом это штаты Аризона, Чиуауа, Колорадо, Нью-Мексико, Сонора и Юта. Дуб горный встречается также в Неваде, Вайоминге, Айдахо, Небраске, Коауиле и западном Техасе[6][7][8][9].
Дерево произрастает на высотах от 1000 до 3000 м над уровнем моря, в областях, где годичный уровень осадков составляет 30—60 см.
Кора дуба чешуйчатая, серая или коричневая.
Листья 7—12 см в длину и 4—6 см в ширину, глубоко рассечены по обе стороны центральной жилки. Их верхняя поверхность тёмно-зелёного цвета и глянцевая, нижняя — более бледная и бархатистая.
Появляющиеся поздней весной цветки обоеполые и представляют собой невзрачные серёжки.
Жёлуди длиной 10—20 мм, растут по одному или парами[6].
Индейцы навахо использовали разные части дуба в медицинских целях, применяя их для смягчения боли при родах, в качестве слабительного, а также церемониального[уточнить] рвотного средства[6].
Дуб Гамбела, или Гэмбела (лат. Quercus gambelii) — небольшое листопадное дерево или крупный кустарник, широко распространённый в предгорьях и невысоких горных возвышенностях Северной Америки.
Описан Томасом Наттоллом в 1848 году. Видовое название растению было дано в честь американского натуралиста Уильяма Гэмбела (англ. William Gambel, 1823—1849).
