|
|
FEIS Home Page |
 |
|
| Muttongrass. Image used with permission of James M. Andre. |
Howard, Janet L. 1997. Poa fendleriana. 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.usda.gov
/database/feis/plants/graminoid/poafen/all.html [].
The scientific name of muttongrass is Poa
fendleriana (Steud.) Vasey (Poaceae) [23,25,30,31,33,47,60]. Recognized
subspecies are:
Poa fendleriana subsp. albescens (A.S. Hitchc.) Soreng, muttongrass
Poa fendleriana subsp. fenderliana, skyline bluegrass [33,47]
Poa fendleriana subsp. longiligula (Scribn. & Will.) Soreng, longtongue muttongrass [30,47]
The genus Poa is extremely uniform, and species determination is
difficult. Muttongrass intergrades and hybridizes with many other Poa
species [48,49,60]. Intergradation with coastline bluegrass (P.
confinis), Wheeler bluegrass (P. nervosa), and Cusick's bluegrass (P.
cusickii) is particularly strong [48]. Welsh and others [60] consider
Cusick's bluegrass synonymous with muttongrass. Based upon chloroplast
DNA analysis and differences in morphologies and mating systems,
however, Soreng [47,48,49] has classified the two taxa as distinct
species. A separate report on Cusick's bluegrass is available in FEIS.
Poa × nematophylla Rydb. is a stable, apomictic taxon probably resulting
from hybridization between muttongrass and a subspecies of Cusick's
bluegrass (P. cusickii ssp. pallida) [49].
Muttongrass occurs from British Columbia east to Manitoba and south to
the Dakotas, western Texas, California, and northern Mexico [30,60].
Subspecies distribution: Poa fendleriana ssp. albescens occurs primarily
in the Sierra Occidental of Sonora and Chihuahua, Mexico, but its
distribution reaches north to southeastern Arizona and southwestern New
Mexico [47,50].
Poa f. subsp. fendleriana occurs from Sonora north to Utah, Colorado, and
western portions of the Dakotas [47,50].
Poa f. subsp. longiligula is the most widely distributed subspecies. It
occurs from Baja California north to British Columbia; east to Manitoba;
and south to Arizona and New Mexico [47,50].
Populations with intermediate morphology occur in transition zones
between subspecies [47].
FRES20 Douglas-fir
FRES21 Ponderosa pine
FRES23 Fir-spruce
FRES28 Western hardwoods
FRES29 Sagebrush
FRES30 Desert shrub
FRES34 Chaparral-mountain shrub
FRES35 Pinyon-juniper
FRES36 Mountain grasslands
FRES37 Mountain meadows
FRES38 Plains grasslands
FRES40 Desert grasslands
FRES44 Alpine
2 Cascade Mountains
3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
6 Upper Basin and Range
7 Lower Basin and Range
8 Northern Rocky Mountains
9 Middle Rocky Mountains
10 Wyoming Basin
11 Southern Rocky Mountains
12 Colorado Plateau
13 Rocky Mountain Piedmont
15 Black Hills Uplift
16 Upper Missouri Basin and Broken Lands
K015 Western spruce-fir forest
K020 Spruce-fir-Douglas-fir forest
K021 Southwestern spruce-fir forest
K023 Juniper-pinyon woodland
K024 Juniper steppe woodland
K031 Oak-juniper woodlands
K032 Transition between K031 and K037
K037 Mountain-mahogany-oak scrub
K038 Great Basin sagebrush
K051 Wheatgrass-bluegrass
K052 Alpine meadows and barren
K055 Sagebrush steppe
K056 Wheatgrass-needlegrass shrubsteppe
K063 Foothills prairie
K065 Grama-buffalograss
K066 Wheatgrass-needlegrass
K067 Wheatgrass-bluestem-needlegrass
K068 Wheatgrass-grama-buffalograss
K069 Bluestem-grama prairie
206 Engelmann spruce-subalpine fir
210 Interior Douglas-fir
217 Aspen
220 Rocky Mountain juniper
237 Interior ponderosa pine
238 Western juniper
239 Pinyon-juniper
240 Arizona cypress
247 Jeffrey pine
256 California mixed subalpine
101 Bluebunch wheatgrass
104 Antelope bitterbrush-bluebunch wheatgrass
107 Western juniper/big sagebrush/bluebunch wheatgrass
210 Bitterbrush
216 Montane meadows
301 Bluebunch wheatgrass-blue grama
314 Big sagebrush-bluebunch wheatgrass
317 Bitterbrush-bluebunch wheatgrass
322 Curlleaf mountain-mahogany-bluebunch wheatgrass
401 Basin big sagebrush
402 Mountain big sagebrush
403 Wyoming big sagebrush
409 Tall forb
410 Alpine rangeland
411 Aspen woodland
412 Juniper-pinyon woodland
413 Gambel oak
415 Curlleaf mountain-mahogany
416 True mountain-mahogany
417 Littleleaf mountain-mahogany
421 Chokecherry-serviceberry-rose
422 Riparian
503 Arizona chaparral
504 Juniper-pinyon pine woodland
509 Transition between oak-juniper woodland and mahogany-oak association
607 Wheatgrass-needlegrass
612 Sagebrush-grass
715 Grama-buffalograss
733 Juniper-oak
Muttongrass is common in sagebrush (Artemisia spp.), scrub oak (Quercus
spp.), pinyon-juniper (Pinus-Juniperus spp.), mountain brush, ponderosa
pine (P. ponderosa), and fir-spruce (Abies-Picea spp.) communities. It
occurs on edges of quaking aspen (Populus tremuloides) communities,
riparian zones, and exposed alpine ridges. It is occasional in desert
shrub and mountain meadow communities and on talus [60]. In Arizona, it
extends from the spruce-fir zone down to desert grassland and Arizona
cypress (Cupressus arizonica) woodland [50].
Kuchler [36] described muttongrass as a dominant understory species in
yellow pine (Pinus ponderosa ssp. scopulorum and P. p. ssp. arizonica)
forests of southern Arizona. Other publications describing plant
communities in which muttongrass is a dominant component of the
vegetation follow.
A preliminary classification of the natural vegetation of Colorado [3]
Sagebrush-steppe habitat types in northern Colorado: a first
approximation [18]
A habitat type classification system for ponderosa pine forests of
northern Arizona [26]
Habitat types on selected parts of the Gunnison and Uncompahgre
National Forests [34]
A classification of spruce-fir and mixed conifer habitat types of
Arizona and New Mexico [38]
A preliminary classification of high-elevation sagebrush-grass
vegetation in northern and central Nevada [39]
Shrub-steppe habitat types of Middle Park, Colorado [54]
Plant associations (habitat types) of Region 2., 3rd ed. [55]
Muttongrass provides good to excellent forage for livestock. It is
considered one of the best forage grasses in Arizona, particularly as
summer feed for domestic sheep. In Colorado, livestock graze muttongrass from early spring to mid-summer [29].
Muttongrass also provides good forage for wildlife. Mountain goat
graze muttongrass [45]. Deer and elk make heavy use of it, especially
in early spring when other green forage is scarce [9,10,53,59].
Depending upon availability of other nutritious forage, deer may use
muttongrass in all seasons [59]. Muttongrass cures well and is an
important fall and winter deer food in some areas [32]. In northern
Colorado, mule deer consumed muttongrass from December until March.
After March, their diet was primarily forbs and green twigs of woody
plants [59].
Palatability of muttongrass is excellent for cattle and horses and good
for elk, deer, pronghorn, and domestic sheep [11,29,32,53]. Muttongrass cures well; palatability of fall foliage is rated as fair in
Arizona [32].
The palatability of muttongrass for small animals has been rated as
follows [11]:
UT WY Small mammals good good Small nongame birds fair good Upland game birds fair good Waterfowl poor poor
Average percent composition and energy content of fresh muttongrass, collected from various locations in the western United States, was as follows [40]:
Protein (N x 6.25,%) 7.0 Digestible energy (kcal/kg) Digestible protein cattle 2.58 cattle 3.8 domestic sheep 2.69 domestic sheep 3.5 horses 3.5 domestic rabbit 4.1 domestic goat 3.1 ash 11.1% Crude fiber 33.5% Ether extract 2.4% N-free extract 46.0%Nutritional content of muttongrass on the Medicine Bow National Forest of Wyoming varied seasonally as follows [5]:
Date Ether Crude Crude Collected Moisture Ash extract fiber protein Carotene ______________________________________________________________ (1947) (%) (%) (%) (%) (%) (?g/g) ______________________________________________________________ 6/10 5.34 7.12 2.72 32.42 8.56 100 7/9 5.85 10.40 2.47 32.87 7.51 59 8/7 6.10 10.39 2.19 32.50 6.12 54 9/4 5.65 11.87 2.29 30.51 5.40 23 10/3 5.99 12.62 1.71 29.54 5.34 7
The degree to which muttongrass provides cover for small animals has been rated as follows [11]:
UT WY Small mammals fair good Small nongame birds fair fair Upland game birds fair fair Waterfowl poor poor
Muttongrass has a deep, fibrous root system that provides good soil erosion control [53]. Use of muttongrass in restoration projects is limited, however, because muttongrass seed is not commercially available [10].
Muttongrass has a deep, fibrous root system that provides good soil erosion control [53]. Use of muttongrass in restoration projects is limited, however, because muttongrass seed is not commercially available [10].
Muttongrass is able to withstand moderately heavy grazing [22,37].
Because of its high forage value and vigor, range managers generally
seek to improve or maintain muttongrass stands. On Arizona rangelands,
it is recommended that at least one-fourth of the previous year's seed
production remains by the time new muttongrass seedheads are ripe in
summer. Degraded ranges should be left to rest in July and August of
alternate years so that muttongrass can increase vigor and set good
seed crops [32].
In Utah juniper (Juniperus osteosperma) rangeland of Arizona, muttongrass and other cool-season grasses were eliminated from the understories
of allotments where continuous cattle grazing had been practiced for
decades. The understories of continuously grazed allotments were
near-monocultures of blue grama (Bouteloua gracilis) with 65 percent
average bare ground. Muttongrass and other cool-season grasses were
present and increasing in abundance on one allotment, however. The
allotment had once been continuously grazed, but a deferred
rest-rotation system had been practiced for the past 20 years. Average
percent composition of muttongrass on ungrazed, continuously grazed,
and rest-rotation grazed sites follows. Soils were similar on all sites
except that soil structure was lacking on continuously grazed sites [4].
Ungrazed* Continuous Rest-Rotation grazing grazing ______________________________________ 45% 0% 25%*The ungrazed site was on a mesa, inaccessible to cattle, where relict vegetation was present.
Muttongrass is a cool-season perennial bunchgrass with occasional short
rhizomes. It is a short to mid-grass with 1- to 2-foot-long (0.3-0.6 m)
culms [29,32,53]. Basal diameter ranges from less than an inch (2.5
cm) to about 1 foot (0.3 m) [32]. Muttongrass is dioecious. Plants
are mostly pistillate, with occasional staminate or perfect flowers
[29,30,50]. Most leaves are basal [29]. The dry, papery sheath bases
of previous years do not readily disintegrate into fibers and are a
conspicuous feature of the species [60].
Muttongrass is drought resistant [7,53,60].
Muttongrass reproduces from seed, by tillering, and rarely, from short rhizomes [53]. Both sexual and apomictic populations reproduce from seed [50]. Lack of pollination is not likely to cause reproductive failure in muttongrass. Asexual regeneration, by tillering and apomixis, is more common in muttongrass than is sexual regeneration [48,49,57,58,61]. Most muttongrass populations have a high preponderance of female plants that produce viable seed without pollination. Averaged over their range, Soreng [47] estimated that Poa fendleriana ssp. fendleriana populations are about 85 percent female. Populations of P. f. ssp. longiligula are mostly or entirely female. Only one male specimen of P. f. ssp. longiligula has ever been collected in New Mexico [47].
Muttongrass occurs mainly on dry sites such as mesas, hillsides, and
dry woods [27,29,47]. It sometimes occurs on wetter sites, however. It
has been noted in riparian zones in Zion National Park, Utah [27].
In a study of 21 burn sites in the Great Basin of California and Nevada,
Koniak [35] found that muttongrass was associated with east slopes.
Muttongrass tolerates a wide range of soil textures [16,18,26,53] and
pH. Muttongrass occurs on limestone soils in the Grand Canyon [26].
On the San Bernardino National Forest of California, muttongrass
occurred on noncarbonate substrates and also on sites that were
surfaced-mined for limestone [21].
Distributions of sexual and apomictic races of muttongrass are linked
to climate. Sexually reproducing populations occur in mild climates
that receive significant summer precipitation. Apomictic populations
tolerate colder and sometimes wetter climates but are restricted by the
Polar Front gradient in the north. They appear to be only slightly more
tolerant to hot desert climates than sexual populations. Apomictic
populations also occur at higher and lower elevations than do their
sexually reproducing counterparts. The total geographic range of Poa
fendleriana ssp. longiligula, for example, is about 20 times broader
than that of sexual P. f. ssp. longiligula [50].
Elevational ranges of muttongrass are as follows:
Arizona - 5,000 to 11,000 feet (1500-3330 m) [32]
California - 10,800 to 13,100 feet (3300-4000 m) [30]
Colorado - 5,000 to 11,500 feet (1500-3450 m) [29]
New Mexico - 4,000 to 11,000 feet (1220-3350 m) [47]
Utah - 3,000 to 12,000 feet (910-3660 m) [60]
Muttongrass occurs in open sun [2,60] to partial shade [2,43]. It
tolerates open, dry conditions better than most herbaceous species. In
the Hualapai Mountains of Arizona, it is the only grass that commonly
occurs on open slopes [7]. It may be more common in partial shade on
very dry sites, however. In Colorado pinyon-alligator juniper (Pinus
edulis-Juniperus deppeana) woodland of central Arizona, muttongrass was
more common under alligator juniper than in openings [8]. In northern
Arizona, muttongrass coverage was significantly greater in communities
with 1 to 10 percent pinyon-juniper (Pinus-Juniperus spp.) canopy
coverage than in communities with lesser or greater percentages of tree
cover [2].
In pinyon-juniper communities, muttongrass is common in initial and/or
early seral stages and persists in mature pinyon-juniper woodland
[8,12,13,14].
Sampson [44] classified muttongrass as seral on wheatgrass (Triticeae)
rangelands of the Intermountain West. He described muttongrass as a
component of the mixed-grass-weed stage. This stage is preceded by the
early and late weed stages and followed by the wheatgrass stage.
Muttongrass is frequently described as a component of or dominant in
climax vegetation in sagebrush (Artemisia spp.) and forest habitat
typings [19,26]. In northern Colorado, Francis [18] reported a mountain
big sagebrush/muttongrass habitat type on shallow skeletal soils that
is probably a topoedaphic climax. Forests with muttongrass tend to
have open structure. Romme and others [43] list muttongrass as a
component of dry-site old-growth ponderosa pine forest on the San Juan
National Forest of Colorado.
Growth generally begins in early spring [29,53], although plants in the Southwest may begin growth in winter [32]. Muttongrass flowers from February to July in New Mexico [47] and from May to August in California and the Great Plains [23,30]. Seed ripened in late May and June on a north-central Arizona site [57]. Seed ripens in June or July in Nebraska [53].
Fires have been variously reported as harming [1,13,12], having no
effect on [57,58,61], or increasing [17] muttongrass. Muttongrass may
be harmed by severe wildfire [13,12]. Most studies suggest that it is
relatively unaffected by prescribed fall burning [24,57,58,61]. One
study, however, reported a long-term (7-year) decrease in muttongrass
after prescribed fall fire [1].
In fire-adapted forest ecosystems, fire is important in maintaining
muttongrass in the herbaceous understory. Muttongrass occurs on open,
sunny sites and in partial shade [2,43,60]; it has not been reported in
closed-canopy forests. Muttongrass is likely to decline as canopy
closure occurs with fire exclusion.
Muttongrass recovers from fire primarily by sprouting from burned
plants. Some muttongrass seedlings establish after fire, but postfire
tillering is probably more important than postfire seedling
establishment in this species [57,58,61].
FIRE REGIMES:
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".
Muttongrass is unharmed to slightly harmed by light-severity fall fire.
Several studies have reported no significant change in muttongrass
following prescribed fall burning [24,57,58,61]. In some cases,
light-severity fall fire can benefit muttongrass by reducing
interference from other herbs [17].
Because muttongrass is a cool-season species that acquires most of its
growth in spring, prescribed spring fire may be more harmful to muttongrass than prescribed fall fire. Literature regarding muttongrass
recovery from spring fire is lacking, however. Muttongrass appears to
be harmed by and slow to recover from severe fire [12,13].
Muttongrass response to fire probably depends upon fire severity. In
Utah juniper-Colorado pinyon of Mesa Verde National Park, Colorado,
muttongrass was present on burn sites representing all stages of
postfire succession except one: an initial postfire community resulting
from a severe fire. Erdman [12,13] sampled vegetation in new (postfire
years 1 to 4), 30-, and 90-year-old burns, and in a Utah juniper-pinyon
woodland that had not burned for 400 years. Muttongrass was not
present on the new burn at postfire year 1, although it is the most
common grass species in Mesa Verde and was present on adjacent unburned
areas. Muttongrass was still absent on the new burn at postfire year
4, the last year of the study. It is likely that muttongrass was
killed by the fire. The fire had killed a 100-year-old stand of
pinyon-juniper, and even sprouting shrubs such as Gambel oak (Quercus
gambelii) showed poor recovery. At postfire year 4, the community was
dominated by forbs and a few exotic perennial grasses that had been
seeded in.
Stand-replacing fires had also occurred on the older burns, but exotic
grasses had not been seeded in after the older fires. Muttongrass was
a dominant component of the vegetation on all older burns and on the
site that had not burned for 400 years. The 30-year-old burn was
codominated by muttongrass and several shrub species. The 90-year-old
burn was dominated by shrubs and had subdominant pinyons and junipers;
muttongrass dominated the herbaceous layer. The site that had not
burned for 400 years was dominated by pinyons and junipers; muttongrass
dominated the herbaceous layer. Muttongrass cover and frequency
percentages on the burn sites were [13]:
% Cover % Frequency ------- ----------- 4-yr-old burn 0 0 30-yr-old burn 4-10 88 90-yr-old burn <4 56 400-yr-old burn 4-10 80Muttongrass recovery after a June 1956 wildfire in shrub live oak-skunkbush sumac (Quercus turbinella-Rhus trilobata) chaparral in Arizona was as follows [41]:
1956 1957 1958 1960 1961 Percent cover 1.0 2.0 2.5 4.0 3.0 Production (lbs/acre) trace trace 8 8 8
Muttongrass showed poor recovery after prescribed fall burning in one study. Over 8 years time, three prescribed November fires were conducted in ponderosa pine in Arizona, resulting in 2-, 5-, and 7-year-old burns. Muttongrass production was less on burned plots than on unburned control plots regardless of time since fire. In contrast, three other bunchgrass species recovered from the fires within 5 years: Their production on the 5- and 7-year-old burns matched or exceeded production on control plots. Production* of muttongrass was as follows [1]:
2-yr-old burn 5-yr-old burn 7-yr-old burn burned plot 0.15 (0.12) 3.49 (1.66) 1.11 (0.34) control plot 3.56 (2.95) 7.44 (1.72)** 2.60 (0.51)** *Production is predicted dry weight (kg/ha) based on basal diameter and regression equations. Data are means (standard errors). **Indicates significant difference (p=0.05) between burn and control
Production of muttongrass and other herbaceous forage was increased by prescribed fire in ponderosa pine near Flagstaff, Arizona. Management objectives were to reduce fuels, thin the forest overstory, and increase ponderosa pine seedling establishment. Prefire litter depth was 1.5 to 3 inches (7 cm). Two one-quarter acre (0.1 ha) areas were burned. Surface fires with average flame lengths of 2 feet (0.6 m) were attained; estimated fire intensities at the two areas were 48 BTUs per second per foot and 90 BTUs per second per foot. Before the fire, herbage production was primarily mullein (Verbascum thapsus), an unpalatable forb. After fire, muttongrass, bottlebrush squirreltail (Elymus elymoides), and palatable herbs were primary producers. Herbage production on one of the burned areas was 3 pounds per acre (3.4 kg/ha) before fire; 40 pounds per acre (45 kg/ha) at postfire year 1; and 40 pounds per acre (45 kg/ha) at postfire year 11. Herbage production on the other area was 5 pounds per acre (5.6 kg/ha) before fire; 5 pounds per acre (5.6 kg/ha) at postfire year 1; and 17 pounds per acre (19 kg/ha) at postfire year 11. The prescribed fire met management objectives, and increased production of palatable forage was an added bonus [17].
Vose, James M.; White, Alan S. 1991. Biomass response mechanisms of understory species the first year after prescribed burning in an Arizona ponderosa-pine community. Forest Ecology and Management. 40: 175-187. [58].
White, Alan S.; Cook, James E.; Vose, James M. 1991. Effects of fire and stand structure on grass phenology in a ponderosa pine forest. The American Midland Naturalist. 126(2): 269-278. [61].
.The study site is located on the Fort Valley Experimental Forest near Flagstaff, Arizona [57,58,61].
The study site is in a ponderosa pine (Pinus ponderosa)/mixed grass community. Overstory structure of the community prior to the fires was a mosaic of patches, each dominated by one of three overstory strata: saplings, pole-sized trees, or sawtimber trees [57,58]. Average density, diameter, and basal area of ponderosa pine in each overstory stratum was [58]:
Density Diameter Basal area _________ ________ __________ sapling 10,070/ha 4.5 cm 15/sq m/ha pole 1,730/ha 15 cm 31/sq m/ha sawtimber 120/ha 63 cm 35/sq m/haThe grass understory was a mixture of muttongrass (Poa fendleriana), mountain muhly (Muhlenbergia montana), and bottlebrush squirreltail (Elymus elymoides). Biomass of muttongrass and mountain muhly in open sawtimber was approximately equal (57 kg/ha); biomass of bottlebrush squirreltail was less (40 kg/ha) [58]. Wheeler's thistle (Cirsium wheeleri) and Wright's deervetch (Lotus wrightii) were important understory forbs. Fendler's ceanothus (Ceanothus fendleri) and Wood's rose (Rosa woodsii var. ultramontana) were also present [57].
Muttongrass had dispersed its seed and was dormant at the time of the fires [61].
The study site had been fenced prior to the study to exclude livestock
and was relatively undisturbed [58,61]. Elevation at the study site is
approximately 6,900 feet (2100 m). Soils are a Brolliar stony clay
loam. Annual precipitation ranges from 109 to 163 inches (430-640 mm)
and averages 127 inches (500 mm). Precipitation patterns are scattered
snowfall and rain in winter months, drought in May and June, and
frequent rains in July and August. Daily mean temperatures range from
23 to 67 degrees Fahrenheit (-5 to 17 oC). July has the highest
monthly mean temperature (61 degrees Fahrenheit (16 oC)), and January
has the lowest (25 degrees Fahrenheit (-4 oC)). Precipitation for
the year following the study was above average [57,58,61].
Fire history of the area suggests that fires burned at approximate
2-year intervals until the late 1800's. Fires have been excluded since
that time [58].
Study plots were prescribe burned on 2 consecutive days in late October 1982. Mean air temperatures were 64 and 57 degrees Fahrenheit (18 and 14 oC). Relative humidity was 21 percent on both days. Strip headfires and backfires were used. Fires were maintained in the understory. The fires consumed 25 to 95 percent of the fuel load and smoldered for several days [57,58]. Two site types were defined in the sawtimber stratum: sites between canopies (Open ST) with minimal litter, and sites below canopies (Below ST) with thick litter accumulations [57]. Based upon heat-yield data and observations, fire severity was ranked: below-canopy sawtimber > pole > sapling > open-canopy sawtimber [58]. Most understory plants in sawtimber patches were between canopies (Open ST), where heat yield averaged only 1,600 kJ/sq m. Fire behavior and fuel data are presented below [57].
Open ST Below ST Pole Sapling Fire behavior Intensity (kW/m) backfires 5 NA 14 17 headfires NA NA 346 294 Rate of spread (m/min) backfires 0.2 NA 0.2 0.3 headfires NA NA 4.5 7.6 Total heat yield (kJ/sq m) 1,600 NA 42,082 15,866 Prefire fuel load (Mg/ha) 17.1 145.9 46.2 30.5 Fuel consumption (%) 25 95 55 33
Neither seedlings nor mature muttongrass plants occurred in sufficient
density on sapling and below-canopy sawtimber plots to warrant analysis
[58]. Data are given for pole and open sawtimber sites only.
Postfire seedling establishment: To help determine if muttongrass or
other herbaceous species were present in the soil seedbank, soil samples
were collected from each forest stratum before the fires. The samples
were spread out on vermiculite in the greenhouse and watered. Muttongrass seedlings did not emerge from soil samples from any of the forest
strata [57].
Seed rain was collected in seed traps on open sawtimber sites for the
first postfire year. Nearly all muttongrass seed dispersed in June.
Total muttongrass seed rain (seeds/sq m) for 1 year on burned and
unburned control sawtimber sites was [57]:
Burn Control ----- ------- 87.31 54.32The first June after the fires, density of muttongrass seedlings was 0.1 seedling per square meter on open sawtimber and pole plots. Muttongrass seedlings were not found on below-sawtimber and sapling plots. Density of muttongrass seedlings remained unchanged on plots of all strata through at least the first October after the fires [57].
Biomass Density _________________________ ______________________ burn control burn control open sawtimber 54.64 (4.81) 56.06 (7.73) 1.81 (0.03) 1.92 (0.04) pole 3.97 (0.56)* 5.08 (0.92) 0.46 (0.12) 0.75 (0.20) __________________________________________________________________ Values are adjusted means (standard errors) from analysis of covariance.*Significant (P<0.05) difference between burn and controlThe number of muttongrass plants producing seed did not change after fire. There were no significant differences in the number of muttongrass plants reaching the seed stage between burned and unburned plots in postfire years 1 and 2. Percentage of plants reaching the seed stage follows [61]. Sample size is indicated in parentheses.
Pole Sawtimber ________________ ________________ Year Burned Unburned Burned Unburned Chi-sq P-value ___________________________________________________________ 1983 29 (7) 38 (8) 74 (19) 44 (18) 6.20 0.102 1984 42 (12) 63 (8) 70 (20) 59 (22) 2.53 0.469
The prescribed fall fires had little effect on muttongrass. In open
sawtimber, mortality rates in the first postfire year were not
significantly different between burned and unburned plots (4% on burned
and 0% on controls). Biomass, density, and number of plants producing
seed after fire were similar on burned and unburned open sawtimber plots
[57,58,61]. On pole plots, density was unaffected by fire. Biomass of
residual plants was significantly greater on unburned pole plots than on
burned pole plots. When biomass of seedlings and residual plants on
pole plots was combined, however, total biomass differences were
insignificant between burned and unburned plots. Lack of fire effect
may be because plants had senesced and were dormant when burned [61].
This study indicates that muttongrass will be unharmed or only slightly
reduced by prescribed fall burning in southwestern ponderosa pine
understories. Tillering was the most important mechanism of postfire
muttongrass regeneration. Although some muttongrass seedlings
established on burned plots, they did not establish in large numbers.
Seed production was unaffected by fire.
1. Andariese, Steven W. 1982. Time-response graphs for understory production following fall prescribed burning in Arizona ponderosa pine on basalt soils. Flagstaff, AZ: Northern Arizona University. 42 p. Thesis. [20307]
2. Arnold, Joseph F.; Jameson, Donald A.; Reid, Elbert H. 1964. The pinyon-juniper type of Arizona: effects of grazing, fire and tree control. Production Research Report No. 84. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station. 28 p. [353]
3. Baker, William L. 1984. A preliminary classification of the natural vegetation of Colorado. The Great Basin Naturalist. 44(4): 647-676. [380]
4. Baxter, Clay. 1977. A comparison between grazed and ungrazed juniper woodland. In: Aldon, Earl F.; Loring, Thomas J., technical coordinators. Ecology, uses, and management of pinyon-juniper woodlands: Proceedings of the workshop; 1977 March 24-25; Albuquerque, NM. Gen. Tech. Rep. RM-39. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 25-27. [17255]
5. Beath, O. A.; Hamilton, J. W. 1952. Chemical composition of Wyoming forage plants. Bull. No. 311. Laramie, WY: University of Wyoming, Agricultural Experiment Station. [5527]
6. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434]
7. Butterwick, Mary; Parfitt, Bruce D.; Hillyard, Deborah. 1992. Vascular plants of the northern Hualapai Mountains, Arizona. Journal of the Arizona-Nevada Academy of Science. 24-25: 31-49. [18327]
8. Clary, Warren P.; Morrison, Douglas C. 1973. Large alligator junipers benefit early-spring forage. Journal of Range Management. 26(1): 70-71. [645]
9. Currie, P. O.; Reichert, D. W.; Malechek, J. C.; Wallmo, O. C. 1977. Forage selection comparisons for mule deer and cattle under managed ponderosa pine. Journal of Range Management. 30(5): 352-356. [4697]
10. Dietz, Donald R.; Nagy, Julius G. 1976. Mule deer nutrition and plant utilization. In: Workman; Low, eds. Mule deer decline in the West: A symposium; [Date of conference unknown]; [Location of conference unknown]. [Logan], UT: College of Natural Resources, Utah Agriculture Experiment Station: 71-78. [6909]
11. Dittberner, Phillip L.; Olson, Michael R. 1983. The plant information network (PIN) data base: Colorado, Montana, North Dakota, Utah, and Wyoming. FWS/OBS-83/86. Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service. 786 p. [806]
12. Erdman, James A. 1970. Pinyon-juniper succession after natural fires on residual soils of Mesa Verde, Colorado. Brigham Young University Science Bulletin. Biological Series. 11(2): 1-26. [11987]
13. Erdman, James Allen. 1969. Pinyon-juniper succession after fires on residual soils of the Mesa Verde, Colorado. Boulder, CO: University of Colorado. 81 p. Dissertation. [11437]
14. Everett, Richard L.; Sharrow, Steven H. 1983. Response of understory species to tree harvesting and fire in pinyon-juniper woodlands. In: Monsen, Stephen B.; Shaw, Nancy, compilers. Managing Intermountain rangelands--improvement of range and wildlife habitats: Proceedings of symposia; 1981 September 15-17; Twin Falls, ID; 1982 June 22-24, Elko, NV. General Technical Report INT-157. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station: 62-66. [897]
15. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
16. Fergus, Ernest N.; Buckner, Robert C. 1973. The bluegrasses and redtop. In: Forage scienes--grassland agriculture. [Place of publication unknown]: [Publisher unknown]: 243-253. On file with: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station, Fire Sciences Laboratory, Missoula, MT. [25523]
17. Ffolliott, Peter F.; Clary, Warren P.; Larson, Frederic R. 1977. Effects of a prescribed fire in an Arizona ponderosa pine forest. Res. Note RM-336. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 4 p. [4750]
18. Francis, Richard E. 1983. Sagebrush-steppe habitat types in northern Colorado: a first approximation. In: Moir, W. H.; Hendzel, Leonard, tech. coords. Proceedings of the workshop on Southwestern habitat types; 1983 April 6-8; Albuquerque, NM. Abluquerque, NM: U.S. Department of Agriculture, Forest Service, Southwestern Region: 67-71. [955]
19. Francis, Richard E.; Aldon, Earl F. 1983. Preliminary habitat types of a semiarid grassland. In: Moir, W. H.; Hendzel, Leonard, tech. coords. Proceedings of the workshop on Southwestern habitat types; 1983 April 6-8; Albuquerque, NM. Albuquerque, NM: U.S. Department of Agriculture, Forest Service, Southwestern Region: 62-66. [956]
20. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998]
21. Gonella, Michael P.; Neel, Maile C. 1995. Characterizing rare plant habitat for restoration in the San Bernardino National Forest. In: Roundy, Bruce A.; McArthur, E. Durant; Halley, Jennifer S.; Mann, David K., compilers. Proceedings: wildland shrub and arid land restoration symposium; 1993 October 19-21; Las Vegas, NV. Gen. Tech. Rep. INT-GTR-315. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 81-93. [24830]
22. Gould, Frank W.; Shaw, Robert B. 1983. Grass systematics. 2d ed. College Station, TX: Texas A&M University Press. 397 p. [5667]
23. Great Plains Flora Association. 1986. Flora of the Great Plains. Lawrence, KS: University Press of Kansas. 1392 p. [1603]
24. Haisley, James R. 1984. The effects of presecribed burning on four aspen-bunchgrass communities in northern Arizona. Flagstaff, AZ: Northern Arizona University. 47 p. Thesis. [27667]
25. Hallsten, Gregory P.; Skinner, Quentin D.; Beetle, Alan A. 1987. Grasses of Wyoming. 3rd ed. Research Journal 202. Laramie, WY: University of Wyoming, Agricultural Experiment Station. 432 p. [2906]
26. Hanks, Jess P.; Fitzhugh, E. Lee; Hanks, Sharon R. 1983. A habitat type classification system for ponderosa pine forests of northern Arizona. Gen. Tech Rep. RM-97. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 22 p. [1072]
27. Harper, K. T.; Sanderson, S. C.; McArthur, E. D. 1992. Riparian ecology in Zion National Park, Utah. In: Clary, Warren P.; McArthur, E. Durant; Bedunah, Don; Wambolt, Carl L., compilers. Proceedings--symposium on ecology and management of riparian shrub communities; 1991 May 29-31; Sun Valley, ID. Gen. Tech. Rep. INT-289. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 32-42. [19092]
28. Harrington, H. D. 1964. Manual of the plants of Colorado. 2d ed. Chicago: The Swallow Press Inc. 666 p. [6851]
29. Herzman, Carl W.; Everson, A. C.; Mickey, Myron H.; [and others]. 1959. Handbook of Colorado native grasses. Bull. 450-A. Fort Collins, CO: Colorado State University, Extension Service. 31 p. [10994]
30. Hickman, James C., ed. 1993. The Jepson manual: Higher plants of California. Berkeley, CA: University of California Press. 1400 p. [21992]
31. Hitchcock, C. Leo; Cronquist, Arthur. 1973. Flora of the Pacific Northwest. Seattle, WA: University of Washington Press. 730 p. [1168]
32. Humphrey, Robert R. 1960. Arizona range grasses: Description--forage value--management. Tucson, AZ: University of Arizona, Agricultural Experiment Station. 104 p. [5004]
33. Kartesz, John T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. Volume II--thesaurus. 2nd ed. Portland, OR: Timber Press. 816 p. [23878]
34. Komarkova, Vera. 1986. Habitat types on selected parts of the Gunnison and Uncompahgre National Forests. Final Report Contract No. 28-K2-234. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 270 p. [1369]
35. Koniak, Susan. 1985. Succession in pinyon-juniper woodlands following wildfire in the Great Basin. The Great Basin Naturalist. 45(3): 556-566. [1371]
36. Kuchler, A. W. 1964. United States [Potential natural vegetation of the conterminous United States]. Special Publication No. 36. New York: American Geographical Society. 1:3,168,000; colored. [3455]
37. Marquiss, Robert; Lang, Robert. 1959. Vegetational composition and ground cover of two natural relict areas and their associated grazed areas in the Red Desert of Wyoming. Journal of Range Management. 12: 104-109. [1529]
38. Moir, William H.; Ludwig, John A. 1979. A classification of spruce-fir and mixed conifer habitat types of Arizona and New Mexico. Res. Pap. RM-207. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 47 p. [1677]
39. Mooney, Melissa Jane. 1985. A preliminary classification of high-elevation sagebrush-grass vegetation in northern and central Nevada. Reno, NV: University of Nevada. 123 p. Thesis. [1689]
40. National Academy of Sciences. 1971. Atlas of nutritional data on United States and Canadian feeds. Washington, DC: National Academy of Sciences. 772 p. [1731]
41. Pase, Charles P.; Pond, Floyd W. 1964. Vegetation changes following the Mingus Mountain burn. Res. Note RM-18. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 8 p. [5700]
42. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843]
43. Romme, William H.; Jamieson, David W.; Redders, Jeffery S.; [and others]. 1992. Old-growth forests of the San Juan National Forest in southwestern Colorado. In: Kaufmann, Merrill R.; Moir, W. H.; Bassett, Richard L., technical coordinators. Old-growth forests in the southwest and Rocky Mountain regions: Proceedings of a workshop; 1992 March 9-13; Portal, AZ. Gen. Tech. Rep. RM-213. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station: 154-165. [19050]
44. Sampson, Arthur W. 1919. Plant succession in telation to range management. Bulletin No. 791. Washington, DC: U.S. Department of Agriculture. 76 p. [3787]
45. Saunders, Jack K., Jr. 1955. Food habits and range use of the Rocky Mountain goat in the Crazy Mountains, Montana. Journal of Wildlife Management. 19(4): 429-437. [484]
46. Shiflet, Thomas N., ed. 1994. Rangeland cover types of the United States. Denver, CO: Society for Range Management. 152 p. [23362]
47. Soreng, Robert J. 1985. Poa L. in New Mexico, with a key to middle and southern Rocky Mountain species (Poaceae). The Great Basin Naturalist. 45(3): 395-422. [2198]
48. Soreng, Robert J. 1990. Chloroplast-DNA phylogenetics and biogeography in a reticulating group: study in Poa (Poaceae) American Journal of Botany. 77(11): 1383-1400. [27549]
49. Soreng, Robert J. 1991. Systematics of the "Epiles" group of Poa (Poaceae) Systematic Botany. 16(3): 507-528. [27716]
50. Soreng, Robert J.; Van Devender, Thomas R. 1989. Late quaternary fossils of Poa fendleriana (muttongrass): Holocene expansions of apomicts. The Southwestern Naturalist. 34(1): 35-45. [9320]
51. Stickney, Peter F. 1989. Seral origin of species originating in northern Rocky Mountain forests. Unpublished draft on file at: U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Fire Sciences Laboratory, Missoula, MT; RWU 4403 files. 10 p. [20090]
52. Stubbendieck, J.; Nichols, James T.; Roberts, Kelly K. 1985. Nebraska range and pasture grasses (including grass-like plants). E.C. 85-170. Lincoln, NE: University of Nebraska, Department of Agriculture, Cooperative Extension Service. 75 p. [2269]
53. Stubbendieck, James; Hatch, Stephan L.; Butterfield, Charles H. 1992. North American range plants. 4th ed. Lincoln, NE: University of Nebraska Press. 493 p. [25162]
54. Tiedeman, James A.; Francis, Richard E.; Terwilliger, Charles, Jr.; Carpenter, Len H. 1987. Shrub-steppe habitat types of Middle Park, Colorado. Res. Pap. RM-273. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 20 p. [2329]
55. U.S. Department of Agriculture, Forest Service, Rocky Mountain Region. 1983. Plant associations (habitat types) of Region 2.,3rd ed. Lakewood, CO. 224 p. [2385]
56. U.S. Department of Agriculture, Soil Conservation Service. 1994. Plants of the U.S.--alphabetical listing. Washington, DC: U.S. Department of Agriculture, Soil Conservation Service. 954 p. [23104]
57. Vose, James M.; White, Alan S. 1987. Processes of understory seedling recruitment 1 year after prescribed fire in an Arizona ponderosa pine community. Canadian Journal of Botany. 65: 2280-2290. [4053]
58. Vose, James M.; White, Alan S. 1991. Biomass response mechanisms of understory species the first year after prescribed burning in an Arizona ponderosa-pine community. Forest Ecology and Management. 40: 175-187. [15570]
59. Wallmo, O. C.; Gill, R. Bruce. 1973. Middle Park deer study: physical characteristics and food habits. In: Federal Aid Completion Report: Project W-38-R-27: WP-14: J4. Denver, CO: Colorado Division of Wildlife: 83-103. [2445]
60. Welsh, Stanley L.; Atwood, N. Duane; Goodrich, Sherel; Higgins, Larry C., eds. 1987. A Utah flora. The Great Basin Naturalist Memoir No. 9. Provo, UT: Brigham Young University. 894 p. [2944]
61. White, Alan S.; Cook, James E.; Vose, James M. 1991. Effects of fire and stand structure on grass phenology in a ponderosa pine forest. The American Midland Naturalist. 126(2): 269-278. [16885]