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Broom
Snakeweed
Common
Name(s):
Broom snakeweed
Snakeweed
Scientific
Name:
Gutierrezia
sarothrae (Pursh) Britt. & Rusby
Scientific
Name Synonyms:
Xanthocephalum sarothrae
(Pursh) Shinners
Symbol:
GUSA2
Description:
Life Span: Perennial
Origin:
Native
Season: Warm
(Short day)
Growth Characteristics:
Broom
snakeweed is a bushy, short-lived, native, perennial shrub or subshrub
that grows from 8 to 28 inches in height. It flowers August to October,
reproduces from seeds. Maximum life span approximately 20 years.
Flowers/Inflorescence:
Numerous
heads are arranged in a flat-topped cluster, which is rounded and
loose. The flower heads are small, with yellow ray flowers. The
bracts are leathery, shiny, green-tipped.
Fruits/Seeds:
Fruit is oval and covered with chaffy scales. A brown, densely hairy,
seed.
Leaves: Alternate,
threadlike leaves which are folded. The margins are entire. Glands
on the leaves do produce resin, making the leaves slightly sticky.
Stems: Twigs
erect, thin, flexible, green to brown, and can be hairy or smooth.
Trunk is short with brown bark which is shreddy and smooth. Stems
die back in the winter giving the plant its broom-like appearance.
Ecological
Adaptations:
Broom
snakeweed occurs on rocky plains, dry foothills, ridgetops, and
mountain slopes, and in semi-desert valleys.
High water use efficiency and a high degree of drought tolerance
enable broom snakeweed to survive on arid or semi-arid sites.
Soils: Broom
snakeweed occurs on a wide range of soil types including dry, well
drained, sandy, gravelly, or clayey loams and heavy clays. Growth
is reportedly best on clay loams of broad alluvial slopes, and shallow,
rocky, or sandy soil. Growth is generally poor on saline or alkaline
soils.
Associated Species:
Big
sagebrush, western wheatgrass,
sandberg bluegrass,
cheatgrass, curlycup
gumweed.
Uses and
Management:
Snakeweed
provides little browse for domestic livestock. It is of minimal
value to cattle and horses, but does provide fair quality winter
browse for domestic sheep when green forage is scarce or lacking.
It is otherwise worthless and can be an indicator of overgrazing.
It's populations are also heavily cyclical, and heavy infestation
can be and indicator of weather conditions rather than overgrazing.
Broom snakeweed can be toxic to domestic sheep, goats, and cattle
particularly during winter or early spring when poor forage availability
forces animals to consume large quantities. Saponins present in
the foliage are responsible for the poisoning, and can cause illness,
death, or abortion in livestock. However, toxicity apparently varies
with phenological stage and substrate. Higher toxicity levels are
often associated with periods of rapid growth, such as early leaf
development, and with growth on sandy rather than calcareous soils.
Broom snakeweed is also a secondary or facultative absorber of selenium,
which may cause illness or death when consumed in quantity.
This plant is commonly confused with rabbitbrush, but it can be
distinguished by the presence of ray flowers. Rabbitbrush plants
have none, nor do the stems die back in the winter.
Southwestern Indians and Mexicans used snakeweed as a broom. Decoctions
were used for indigestion. Pieces of the plant were chewed and placed
on bee and wasp stings.
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