Postfire establishment patterns:
Success of postfire germination and
establishment of pointleaf manzanita varies greatly across sites and is believed
to be the result of fire severity (see "Fire severity and postfire
establishment" below) and postfire site conditions.
For example, in central Arizona Lindenmuth and Glendening [62] found pointleaf manzanita produced "many"
seedlings during the 1st spring after a wildfire. However, seedling mortality rates
were high, with only 10% of seedlings surviving after the 1st dry season.
Mortality was attributed to drought and rooting and trampling by collared peccaries.
In a Madrean oak woodland near
Tucson, Arizona, postfire establishment was monitored after wildfire in July.
Pointleaf manzanita establishment rates were "very low" 1 to 2 years following
burning. In some areas it showed no postfire establishment, while
other areas showed "minimal" recruitment after burning. From these observations
the authors categorized pointleaf manzanita as intolerant to fire [16].
In contrast, studies have shown successful postfire establishment of
pointleaf manzanita. In La MichilÃa Biosphere
Reserve, Durango, Mexico, pointleaf manzanita showed "strong" seedling
emergence following an "intense" wildfire. Pointleaf manzanita stem densities were
491 stems per hectare on unburned plots compared to 4625 stems per
hectare on adjacent burned plots 11 months after burning [34]. In a central Arizona
shrub live oak-skunkbush sumac community, Pase and Pond [86] found that pointleaf manzanita
density was 486 seedlings/acre 1 year after a wildfire. At postfire year 4, pointleaf manzanita had
declined to 335 seedlings/acre but showed signs of "vigorous growth."
Also in central Arizona, Pase and Lindenmuth [85] found "abundant"
regeneration and "vigorous growth" of pointleaf manzanita seedlings 1 to 5 years
following prescribed fire in a shrub live oak-mountain-mahogany
community. However, mortality of pointleaf manzanita seedlings was high
following emergence during the summer dry seasons
(see Fire Case Studies).
Fire severity and postfire establishment:
During the mid-20th century, stand conversion of pointleaf manzanita and other
chaparral species to grasslands was rationalized by grazing needs, potential
wildlife habitat improvement, and aesthetics. A common tactic during chaparral
conversions involved the use of low-severity prescribed fire. Lathrop and Martin
[59] found that prescribed fire conducted in southern California Jeffrey pine-California black oak
woodlands during the winter killed pointleaf manzanita plants but was not severe
enough to break dormancy of belowground banked pointleaf manzanita seeds.
Burning resulted in a significant reduction (93%, p<0.01) in density and basal area of pointleaf
manzanita in burned areas compared to adjacent unburned stands 2 years following fire.
Fire frequency and postfire establishment:
Research conducted during the mid-20th century focused on the timing and frequency of burning as means of
reducing stands of pointleaf manzanita (see Fire severity and postfire
establishment above). Pointleaf manzanita can be eliminated in areas where fires are frequent
enough to kill young plants that have not matured enough to produce
a seed crop [13,17]. One experimental burn in montane chaparral in California, conducted 3 years after a fire on a
young stand of pointleaf manzanita, resulted in 100% mortality of all plants. No new seedlings established [13].
The Research Project Summary
Response of vegetation to prescribed burning in a Jeffrey pine-California
black oak woodland and a deergrass meadow at Cuyamaca State Park, California,
provides information on prescribed fire and postfire responses of many plant community species including
pointleaf manzanita.
Pointleaf manzanita provides food and cover for wildlife and livestock
[10,26,51,64,66,68,80,107]. Many frugivorous animals eat the berries, including
blue grouse, Montezuma quail, wild turkeys, Gambel's quail, white-tailed deer, mule deer,
American black bears, coyotes, hooded skunks, and collared peccaries
[10,26,51,66,68,80,107]. Domestic goats prefer pointleaf manzanita browse.
One of only several populations of pointleaf manzanita in Texas is reported to
be decreasing due to browsing pressure by domestic goats [37,51].
Palatability/nutritional value:
Palatability of pointleaf manzanita is considered "low" for deer species [81].
Cover value: The Chauilla
people considered stands of pointleaf manzanita excellent cover for white-tailed and mule
deer and desert bighorn sheep [10]. Hooded skunk, white-tailed deer, mule deer, blue grouse,
Montezuma quail, Gambel's quail, desert kangaroo rats, American black bears, coyote, and numerous bird
species are found in stands of pointleaf manzanita
[10,51,66].
Pointleaf manzanita occurs as a primary understory species in Madrean pine-oak
(Pinus-Quercus spp.) woodlands
in southern Arizona and New Mexico, western Texas, and Mexico.
Associated tree species include shrub live oak (Q. turbinella), Mexican blue oak (Q. oblongifolia),
Emory oak (Q. emoryi), Palmer oak (Q. dunnii), Arizona white oak (Q. arizonica), silverleaf oak
(Q. hypoleucoides), Mexican pinyon (P. cembroides),
Chihuahua pine (P. leiophylla var. chihuahuana),
Arizona cypress (Cupressus arizonica), Arizona rosewood (Vauquelinia californica),
alligator juniper (Juniperus deppeana), oneseed juniper (J. monosperma),
and birchleaf mountain-mahogany (Cercocarpus betuloides).
Important shrubs include Wright silktassel (Garrya wrightii), ashy silktassel (G. flavescens),
Palmer's century plant (Agave palmeri), Schott's century plant (A. schottii),
Pringle manzanita (Arctostaphylos pringlei), desert ceanothus (Ceanothus
greggii), skunkbush sumac (Rhus
trilobata), sugar sumac (R. ovata), Stansbury cliffrose (Purshia mexicana var.
stansburiana), Wilcox's barberry (Berberis wilcoxii), Wheeler
sotol (Dasylirion wheeleri), sacahuista (Nolina microcarpa),
Schott's yucca (Yucca schottii), banana yucca (Y. baccata),
and wait-a-minute (Mimosa aculeaticarpa var. biuncifera). Grasses include sideoats grama (Bouteloua
curtipendula), bull grass (Muhlenbergia emersleyi), and mutton grass (Poa
fendleriana) [3,16,17,23,28,30,57,67,78,83].
Pointleaf manzanita is found in the understory of pinyon-juniper (Juniperus
spp.) woodlands in southwestern New
Mexico. This cover type is typical of low to mid-slopes on eastern
exposures at elevations from 6,365 to 7,875 feet (1,940-2,400 m) elevation. Dominant trees
in this type include Colorado pinyon (P. edulis), Mexican pinyon, singleleaf pinyon (P.
monophylla), alligator juniper, Utah juniper (J. osteosperma), birchleaf mountain-mahogany,
gray oak (Q. grisea), and shrub live oak.
Graminoid associates include blue grama (Bouteloua gracilis), pine muhly
(M. dubia), and common wolfstail (Lycurus phleoides)
[47,74,104].
Pointleaf manzanita is a common shrub in Arizona and New Mexico's interior chaparral.
This vegetation type, found along the Mogollon Rim, is dominated by shrubs and
small trees. Shrub associates include Pringle manzanita, sugar sumac, skunkbush
sumac, smooth sumac (R. glabra), deer brush (C. integerrimus),
Mojave ceanothus (Ceanothus greggii var. vestitus), Mohave buckbrush (C. g.
var. perplexans), redberry buckthorn (Rhamnus crocea), Wright
silktassel, wait-a-minute, narrowleaf yerba santa (Eriodictyon
angustifolium), and sacahuista. Shrubby tree associates may include shrub
live oak, Nuttall's scrub oak (Q. dumosa), curlleaf mountain-mahogany (Cercocarpus ledifolius),
and hairy mountain-mahogany (C. montanus var.
paucidentatus). Larger trees such as Chihuahua pine, interior ponderosa pine (P.
ponderosa var. scopulorum), border pinyon (P.
discolor), alligator juniper, Emory oak, silverleaf oak, and Arizona white
oak may have scattered occurrences. Important grasses include lemon grass (Cymbopogon
citratus), Orcutt's threeawn (Aristida
schiedeana var. orcuttiana), and bull muhly (M. emersleyi) [18,24,44,51,63,67,69,84].
The most diverse community where pointleaf manzanita occurs is
the montane chaparral of the higher-elevation Coastal Ranges of northern, central,
and southern California, the Transverse and Peninsular ranges of southern California, and the
Sierra San Pedro Mártir of northern Baja California.
Characteristic species that associate with pointleaf manzanita in montane
chaparral include whiteleaf manzanita, bigberry manzanita (A.
glauca), yerba santa (E. californicum), eastern redbud (Cercis
canadensis), wedgeleaf ceanothus (Ceanothus cuneatus), California buckthorn (Frangula californica ssp.
cuspidata), common snowberry (Symphoricarpos albus), birchleaf mountain-mahogany, thickleaf yerba santa (E.
crassifolium), flannelbush (Fremontodendron californicum), California
coffeeberry (Rhamnus californica), and yellowleaf silktassel (G. flavescens) [2,27,40,59,71].
Tecate cypress (Cupressus forbesii)
may associate in southern California and northern Baja California [25]. Montane chaparral
often succeeds to Jeffrey pine (P.
jeffreyi), Coulter pine (P. coulteri), and Pacific
ponderosa pine (P. ponderosa var. ponderosa), and/or California
black oak (Q. kelloggii) [2,27,40,59,71].
Chamise (Adenostoma fasciculatum) chaparral is the most common type of chaparral in California,
occurring in the North and Central Coast Ranges, Sierra Nevada foothills,
southern California, and northern Baja California. Whiteleaf
manzanita (Arctostaphylos
viscida) may codominate with chamise on some sites. Pointleaf manzanita and
other associated species are infrequently in this type. Associated shrubs
include Nuttall's scrub oak, laurel sumac (Malosma laurina), white
sage, (Salvia mellifera), black sage (S. apiana), sugar sumac, and
eastern Mojave buckwheat (Eriogonum fasciculatum). Giant wildrye (Leymus condensatus)
is a common grass associate [43,73].
Pointleaf manzanita is found in the understory of oak woodlands of the
lower-elevation Coastal Ranges of northern, central, and southern California, the Transverse and
Peninsular ranges of southern California, and the
Sierra San Pedro Mártir of northern Baja California.
Oak woodlands vary in structure from open savanna to dense woodland with a
shrubby understory. They merge or form a mosaic with annual
grassland at low elevations and with montane chaparral at higher elevations.
Overstory associates include valley oak (Q. lobata), coast live oak (Q. agrifolia), interior live
oak (Q. wislizenii),
California shrub live oak (Q. turbinella var. californica), leather oak (Q. durata),
canyon live oak (Q. chrysolepis), blue oak (Q. douglasii),
California black oak, Coulter pine, gray pine (P. sabiniana),
and California buckeye (Aesculus californica).
Common shrub associates include wedgeleaf ceanothus,
coffeeberry, chamise, poison-oak, and toyon (Heteromeles arbutifolia). Some common ground cover
associates are annual bluegrass (Poa annua), annual fescues (Vulpia spp.),
annual ryegrass (Lolium multiflorum), medusahead (Taeniatherum caput-medusae),
ripgut brome (Bromus rubens), wild oat (Avena fatua), and bur clover (Medicago
polymorpha) [9,39].
Classifications describing plant communities in which pointleaf manzanita is
a dominant species are as follows:
Pointleaf manzanita was an important food of the Chauilla. Stands of
pointleaf manzanita
were managed by the Chauilla for production of food, firewood, and construction materials.
The fruits were smashed and used to
make a beverage, eaten raw, or made into a cake. Leaves were occasionally
mixed with tobacco for smoking or used in a tea for several types of remedies
[10]. The Navajo smoked the leaves of pointleaf manzanita for good luck
[101]. A decoction using the leaves of pointleaf manzanita was locally used in
Arizona and New Mexico as a remedy for stomach trouble [51,89].
The fruits of pointleaf manzanita are edible and are commonly used in jelly, and sold in markets
in Mexico [51,89]. The leaves and fruit of pointleaf manzanita are used in
Mexican household remedies for dropsy, bronchitis, venereal diseases, and other
infections [19].
Pointleaf manzanita is sometimes used for fuelwood in Arizona and New Mexico,
although it is considered "nondesirable" fuel [11].
Pointleaf manzanita regenerates from seed or through layering [19,102].
Breeding system:
Pointleaf manzanita is monoecious [49].
Pollination is insect mediated [49].
Seed production:
Pointleaf manzanita produces "prolific" or "many" seeds
[62,84]. Quantitative measurements of seed crops are not available as of this
writing (2005).
Seed dispersal:
No information is available on this topic.
Seed banking:
Pointleaf manzanita seeds remain viable in the soil for decades [18,84,86].
Germination of pointleaf
manzanita is stimulated by scarification of seed by fire [18,23,34,85].
Seedling establishment/growth:
Pointleaf manzanita is widely considered an "obligate seeder" or
"fire-recruiter." Regeneration depends almost entirely on germination from seed
after fire [19,84,85,103]. During the spring after burning,
varying numbers of pointleaf manzanita seedlings appear. High mortality rates are common
the 1st year after seedling establishment, possibly because of summer
drought [62]. Pointleaf manzanita seedlings reach heights
of 14 to 16 inches (35-40 cm) 2 years after fire [17].
Asexual regeneration:
Pointleaf manzanita regenerates by layering when branches that lie on
the ground for extended periods (>2 years) take root [17,102].
Succession in stands where pointleaf manzanita
occurs is not easily predicted and depends on a number of variables including plant association,
community type, proximity to boundaries with other communities, geographic and topographic
location, climate, fire severity, and time since last fire [41].
Pointleaf manzanita occurs in a "fire-induced climax association." This
is defined as species that must have fires at regular intervals to maintain dominance. Stand-level
regeneration of pointleaf manzanita occurs
after fire that scarifies long-lived, soil-stored seed. Depending on geographic location,
moisture availability, and time since last fire, fire exclusion results in the
successional replacement of pointleaf manzanita [18]. This is especially
apparent at the upper elevational limits of pointleaf manzanita, where chaparral or oak woodlands
transition to higher, more mesic pine forests. In these areas, very old stands of pointleaf manzanita
are susceptible to encroachment by
conifers [16,76,79,84].
Stands where pointleaf manzanita occurs change rapidly during the first 1 to 4
postfire years. In areas
where pointleaf manzanita associates with sprouting shrub species, postfire
succession can typically be described in 3 stages: (1) During the 1st postfire
year, grasses and forbs form the dominant cover, while chaparral
shrub seedlings and sprouts emerge. (2) During the 2nd postfire year, mortality of shrub and subshrub seedlings
is high. (3) In subsequent years, the remaining
shrub seedlings and sprouts become well established while herbaceous vegetation
gradually decreases. After 8 to 10 postfire years, a relatively mature chaparral cover
with little understory exists [23,41,98].
Between fires vegetative regeneration by layering occurs on the perimeters of parent shrubs and
creates a discrete age and size "aggregate" from the center of the parent shrub to
the outside of the aggregate. This assemblage may resemble one large
individual shrub. As the parent shrub ages, it often senesces and dies while the aggregates continue growth leaving
a "fairy ring" growth pattern [17].
Arctostaphylos pungens, with the common name pointleaf manzanita, is a species of manzanita. It is native to the Southwestern United States and to northern and central Mexico, where it grows in chaparral and woodland habitats, and on desert ridges. Arctostaphylos pungens can be seen growing at Tent Rocks National Monument in New Mexico at an elevation of about 6000 feet.
Arctostaphylos pungens is an erect, spreading, evergreen shrub growing to heights between one and three meters. It has smooth red bark. Its smaller twigs and new leaves are lightly woolly. Mature leaves are leathery, shiny and green, oval to widely lance-shaped, and up to 4 centimeters long. The inflorescence is a spherical cluster of urn-shaped manzanita flowers. The fruit is a drupe 5 to 8 millimeters wide.[2]
It is a food source for many kinds of wildlife, and it is harvested by people and made into jam in many parts of Mexico.[2][3]
This shrub thrives in dry, shallow, acidic soils heavy with gravel and sand, and forms relationships with mycorrhizae to obtain extra nutrients and water.[2] The seeds require scarification by wildfire before they are able to germinate.
Arctostaphylos pungens, with the common name pointleaf manzanita, is a species of manzanita. It is native to the Southwestern United States and to northern and central Mexico, where it grows in chaparral and woodland habitats, and on desert ridges. Arctostaphylos pungens can be seen growing at Tent Rocks National Monument in New Mexico at an elevation of about 6000 feet.
