Pygmy Sagebrush

Artemisia pygmaea is a distinctive, faintly aromatic shrublet, often mistaken for something other than a sagebrush. In early spring its stiff, bright green, deeply pinnatifid leaves are reminiscent of some prickly member of Polemoniaceae. After flowering, its heads and narrow panicles easily identify it as a member of Artemisia; it is unlike other members of the subgenus (which typically have 3-lobed leaves in fascicled lateral shoots). The molecular analysis by L. E. Watson et al. (2002) supported its phylogenetic alignment within subg. Tridentatae.

Shrubs, 5–10 cm, slightly aromatic; not root-sprouting (caudices coarsely woody, branched). Stems pale to light brown (stiffly erect, densely clothed with appressed foliage), sparsely tomentose. Leaves persistent (sessile, rigid), bright green; blades oblong to ovate, 0.3–0.5 × 0.2–0.3 cm, pinnately lobed (nearly to midribs, ¹/3+ widths of blades, lobes 3–7, divergent), faces glabrous or sparsely tomentose, resinous. Heads (sessile, erect) in paniculiform to racemiform arrays (1–)2–3 × 0.5–1 cm. Involucres narrowly turbinate, 2–3 × 3–4 mm. Phyllaries (green) narrowly lanceolate (midribs prominent), glabrous or sparsely tomentose. Florets 2–6; corollas 2.5–3 mm, glandular (style branches flat, erose, exsert). Cypselae (prismatic) 0.4–0.5 mm, glabrous, resinous. 2n = 18.

Seriphidium pygmaeum (A. Gray) W. A. Weber

Pygmy sagebrush's distribution is limited to interior deserts and plateaus
of the southwestern United States. Its distribution is limited to
approximately 20 miles² (54k m²)
in western Nevada, Utah, northern
Arizona, and northwestern Colorado [3,6,53]. Pygmy sagebrush is rare in Colorado and Arizona [17],
and it is uncommon but locally abundant in the Great Basin of east-central and eastern Nevada [8,12,17,21,26,45,53,55] and the Uinta Basin of
western, central, and northeastern Utah [8,12,15,18,21,25,26,45,47,53,55]. It
occurs irregularly in extreme western
Rio Blanco County, Colorado [54], northwestern Coconino County, Arizona [8,18,19,56], and
in New Mexico [17,50]. A state distributional map of pygmy sagebrush can be accessed through Plants database.

More info for the terms: fire frequency, fire regime, frequency, seed

Fire adaptations:
Pygmy sagebrush does not sprout after a disturbance such as fire [52]. As of
this writing (2005), little is known of the fire ecology of pygmy sagebrush.
Pygmy sagebrush may be similar to other woody sagebrush taxa, establishing
primarily from on-site seed sources after fire. Much research is needed to
understand the life history, successional status, and fire ecology of this
species.

FIRE REGIMES:
Habitats of dwarf sagebrush species such as pygmy sagebrush seldom support enough
vegetation to carry a fire [6]; however, invasive annuals
such as cheatgrass (Bromus tectorum) can increase fire frequency in sagebrush
communities [25].

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

Community or Ecosystem Dominant Species Fire Return Interval Range (years)
silver sagebrush steppe Artemisia cana 5-45 [13,41,58]
sagebrush steppe A. tridentata/Pseudoroegneria spicata 20-70 [37]
basin big sagebrush A. tridentata var. tridentata 12-43 [43]
Wyoming big sagebrush A. tridentata var. wyomingensis 10-70 (40**) [51,59]
saltbush-greasewood Atriplex confertifolia-Sarcobatus vermiculatus <35 to <100
desert grasslands Bouteloua eriopoda and/or Pleuraphis mutica <35 to <100
blackbrush Coleogyne ramosissima <35 to <100
pinyon-juniper Pinus-Juniperus spp. <35 [37]
interior ponderosa pine* Pinus ponderosa var. scopulorum 2-30 [1,2,23]


*fire return interval varies widely; trends in variation are noted in the species review

Additional information on the response of pygmy
sagebrush to fire is necessary before management considerations are proposed.

More info on this topic.

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

More info for the term: cover

SAF COVER TYPES [10]:





237 Interior ponderosa pine

239 Pinyon-juniper

More info on this topic.

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

More info for the term: shrub

ECOSYSTEMS [28]:





FRES21 Ponderosa pine

FRES29 Sagebrush

FRES30 Desert shrub

FRES35 Pinyon-juniper

More info on this topic.

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

More info for the term: woodland

KUCHLER [22] PLANT ASSOCIATIONS:




K023 Juniper-pinyon woodland

K038 Great Basin sagebrush

K039
Blackbrush

K040 Saltbush-greasewood

K055 Sagebrush steppe

More info on this topic.

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

More info for the terms: cover, shrub

SRM (RANGELAND) COVER TYPES [46]:




212 Blackbrush

401 Basin big sagebrush

403 Wyoming big sagebrush

405 Black sagebrush

406 Low sagebrush

408 Other sagebrush types

414 Salt desert shrub

501 Saltbush-greasewood

504 Juniper-pinyon pine

Fire kills pygmy sagebrush. The aboveground woody parts are often completely consumed by fire [6].

More info for the terms: cover, selection

Pygmy sagebrush provides little value to livestock and
large mammals due to its scarcity and small size [7,14,16,27,31,32]. It is
important to small animals on some sites
(see Cover value).

Palatability/nutritional value:
The overall browse value of pygmy sagebrush is low [14]. The
palatability of pygmy sagebrush in Utah is rated as follows [9]:

Cattle Poor
Domestic Sheep Fair
Horses Poor
Pronghorn Fair
Elk Poor
Mule Deer Poor
Small mammals Fair
Small nongame birds Poor
Upland game birds Fair
Waterfowl Poor

The composition and concentration of volatile oils in plants may influence
the selection of food plants by ruminants such as pronghorn and mule deer. The
following table represents the average utilization of pygmy sagebrush by mule
deer and relative percent concentration of 3 major volatile compounds in pygmy
sagebrush in Utah [44]:

Utilization Methacrolein Alpha-pinene Arthole
54% 0.35% 28.42% 1.62%

Cover value:
Pygmy sagebrush provides important
ground cover for small animals in dry, alkaline areas where it is
difficult for other plants to grow [16,27,31,32,33].

More info for the terms: chamaephyte, dioecious, grassland, litter, seed, shrub, succession, xeric

Pygmy sagebrush grows in specific, limited habitats [26] and is a component of communities with rare
plant species [56]. It  occurs primarily in desert grassland, salt
desert shrub, pinyon-juniper (Pinus-Juniperus spp.), and interior ponderosa pine (Pinus ponderosa
var. scopulorum) communities of the Great Basin and Uinta Basin [56].

In Utah, pygmy sagebrush occurs in black
sagebrush  (Artemisia nova) [6,16,31,32,33,56], rabbitbrush (Chrysothamnus spp.), shadscale
(Atriplex confertifolia), greasebush (Glossopetalon spp.),
juniper, pinyon-juniper, and ponderosa pine communities [56].

In Nevada, it occurs with halophytic threadleaf rubber
rabbitbrush (C. nauseosus ssp. consimilis) [6,12,16,31,32,33] and is also associated with
saltbush (Atriplex spp.) [18].


BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Artemisia pygmaea

• GENERAL BOTANICAL CHARACTERISTICS
• RAUNKIAER LIFE FORM
• REGENERATION PROCESSES
• SITE CHARACTERISTICS
• SUCCESSIONAL STATUS
• SEASONAL DEVELOPMENT

GENERAL BOTANICAL CHARACTERISTICS:


This description provides characteristics that may be relevant to fire ecology,
and is not meant for identification. Keys for identification are available [3,6,7,8,12,15,18,19,53,54,55,56].

Pygmy sagebrush is a dwarf, cushionlike,
evergreen, perennial native shrub. This desert species exhibits numerous
morphological adaptations that enable it to live in very xeric sites. It grows
no taller than 8 inches (20 cm). Leaves on the vegetative stems are
nearly glabrous, between 0.08 to 0.16 inch (2-4 mm) wide, 0.08 to 0.32 inch (2-8 mm) long, and are pinnatifid
with 3 to 11 lobes, or sometimes may be only toothed [8,18,56]. Leaves on the flowering branches are usually
reduced and may be entire [6,27,31,32,33]. The flower head contains 3 to 5 disc flowers arranged into spikelike
inflorescences. Ray flowers are lacking. Fruits are glabrous or
resinous-glandular achenes
[8,56]. Seeds are large for Artemisia species [6,27];
however, quantitative seed measurements are not available. Pygmy
sagebrush has a taproot [56].

RAUNKIAER [42] LIFE FORM:


Chamaephyte


REGENERATION PROCESSES:


Breeding system:
Pygmy sagebrush is dioecious [3].

Pollination:
Artemisia species are wind- and self pollinated [3].

Seed production:
Pygmy sagebrush is reportedly capable of producing large quantities of seed [49],
but quantitative counts are not available.

Seed dispersal:
Artemisia seeds have very poor dispersal due to a lack of appendages for airborne
transport. Most seed falls beneath the parent plant, and populations expand 3 feet (0.9 m) or less per
generation [45].

Seed banking:
No information is available on this topic.

Germination:
Specific information on the germination of pygmy sagebrush is unavailable. Artemisia
seeds may germinate within 48 hours and produce cotyledons in 4 days [3].

Seedling establishment/growth:
Artemisia seed falls too late to germinate that fall. No evidence has
shown that fall-dispersed seed surviving through summer can germinate in its 2nd fall. Survival of seed is related to the litter layer. The less the litter, the
more likelihood of seed survival [3].

Asexual regeneration:
There have been no reports of pygmy sagebrush reproducing asexually in the wild.


SITE CHARACTERISTICS:


Pygmy sagebrush occurs in extremely xeric conditions [21,47] and can be found in
specific, limited habitats [26,49] such as
valley bottoms and shallow slopes below the mountains [45].
It is restricted to shale barrens at low elevations [47].

Elevations where pygmy sagebrush occurs range from 4,500 feet (1,400
m) to 11,000 feet (3,300 m). Elevational ranges by state are shown below.

Arizona 4,500 feet ( 1,400 m) [19]
Nevada 5,000-11,000 feet (1,500-3,300 m) [18]
Utah 5,200-7,500 feet (1,600-2,300 m) [56]

Soil: Pygmy sagebrush is
restricted to desert calcareous soils in the Great Basin and Uinta Basin
[3,6,14,15,18,20,21,25,26,33,45,53,55]. It prefers alkaline
soils [8,12,40] with a high clay content [45]. Pygmy sagebrush reportedly grows on white gypsum outcrops in northern and central Nevada
[7]. In Arizona it grows on Green River shale, clay
soils forming the matrix in igneous gravels, calcareous gravels, dolomitic outcrops,
and gravels [56].

Climate:
Mean annual precipitation within the range of pygmy sagebrush is approximately
7.9 to 11.8 inches (200-300 mm) [33].


SUCCESSIONAL STATUS:


Pygmy sagebrush's place in succession is unclear and requires further study.
Beetle [3] suggests topographic and edaphic "climax" for all species within
Artemisia.


SEASONAL DEVELOPMENT:


Pygmy sagebrush flowers in August and September [6,8,16,18,27,31,32,33], and its seed
matures in October [6,27].

Very little is known about pygmy sagebrush, and more research is
needed on this species.

The small size of pygmy sagebrush and its limited distribution preclude commercial uses [12].

Pygmy sagebrush does not sprout [6].

More info for the terms: ground residual colonizer, secondary colonizer, seed

POSTFIRE REGENERATION STRATEGY [48]:




Ground residual colonizer (on-site, initial community)

Secondary colonizer (on-site or off-site seed sources)

More info on this topic.

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

BLM PHYSIOGRAPHIC REGIONS [4]:





6 Upper Basin and Range

7 Lower Basin and Range

10 Wyoming Basin

12 Colorado Plateau

(key to state/province abbreviations)

UNITED
STATES

AZ CO NV NM UT

More info for the term: seed

Pygmy sagebrush is a good candidate for heavy soils plantings, and
may be planted on mine and roadway disturbances [16,32,33]. It establishes readily by
transplanting divided plants. As of this writing (2005), artificial seed
regeneration has not been
successful [16,27,31,32,33].

Artemisia pygmaea A. Gray, Proc. Am. Acad. 21: 413. 1886
A low undershrub, with a thick cespitose woody caudex; stems about 1 dm. high, glabrous; leaves less than 1 cm. long, glabrous, or slightly canescent, pinnately dissected into 3-7 short linear-spatulate rigid divisions, with strong midribs; heads few in a spike-like inflorescence; involucre turbinate, 4 mm. high, 3 mm. broad; bracts 12-15, in 3 or 4 series; the outer ovate or lanceolate, acute, somewhat keeled, herbaceous, slightly puberulent; inner bracts linear, oblong, obtuse, yellowish, thin; flowers 3-4; corollas elongate-fuimelform, 3 mm. long, glandular-granuliferous; style included; achenes glabrous, 1 mm. long or more.
Type locality: Fish Creek, near Eureka, Nevada. Distribution: Nevada and Utah.

Artemisia pygmaea is a North American species of sagebrush in the aster family known by the common name pygmy sagebrush.