Eriogonums constitute a large, exclusively North American genus belonging 

 to the buckwheat family (Polygonaceae). On a conservative basis at least 175 

 species of Erfoffonum, occur in the western United States, the group ranking 

 among the three largest genera of range plants. The buckwheat family also 

 includes the well-known knotweeds (Polyyonum spp.), docks (Rumcx spp.), 

 and such commonly cultivated plants as rhubarb (Rheum rhaponticum) and 

 buckwheat (Fagopyrwn csculentum). Although sometimes known as wiklbuck- 

 wheats, the eriogonums do not strikingly resemble their buckwheat cousin, ex- 

 cept for their three-angled achenes. 



Growth habit within the genus is variable. The species may be frail an- 

 nuals, herbaceous perennials, part shrubs, or genuine shrubs. Practically all 

 species have well-developed taproots; some of the part shrubs have spreading 

 or prostrate stems, which tend to root at the joints or near the ends. The 

 herbaceous eriogonums frequently have but one main stem, which may be 

 either simple or branched, and with or without leaves. Those species inclined 

 to be shrubby usually have several stems, but often the flower-bearing portions 

 are herbaceous, erect, and leafless (scapelike). The leaves are simple and 

 entire, and in many herbaceous species are basal, but they may also occur 

 alternately or in whorls on the stems; they are short-white-woolly in many 

 species, but are dark green and hairless in some, at least on the upper surface. 

 The individual flowers, mostly borne on tiny stalklets, are perfect, typically 

 small, and usually occur in groups of several flowers, more or less protruding 

 from a four- to eight-toothed flower-cluster cup (involucre). Although true 

 petals are lacking, the more or less united outer flower parts (calyx, or peri- 

 anth) are colored, petallike, six-parted or cleft and are persistent around the 

 single, usually three-angled "seed" (achene) ; there are nine stamens. The 

 flower clusters may be borne in heads, in stalked, umbrella-shaped groups 

 (umbels), or scattered along the flowering branches, or at the ends of scapelike 

 stems. 



The eriogonums appear at practically all elevations, from sea level to above 

 timber line. However, throughout their range they are plants of essentially 

 dry situations, preferring rocky, sandy, and well-drained soils in regions of 

 moderate or low rainfall, and can even withstand long and dry summers. They 

 almost invariably grow in exposed, sunny, and warm sites, even when asso- 

 ciated with brush, coniferous, or other woodland types. The genus is perhaps 

 most abundantly represented in the foothill areas, especially those bordering the 

 deserts of the Intel-mountain region. 



As a group the eriogonums are inferior forage plants. Their use is limited 

 largely to spring and fall or winter. In the spring the new growth, especially 

 in the herbaceous species, is somewhat succulent, so that livestock tend to crop 

 it, or to nip off the flower heads as they develop. Because of the absence of 

 more palatable forage during the fall or winter, the somewhat shrubby species 

 are at least slightly grazed. Taken as a whole, the eriogonums, so far as their 

 herbage is concerned, probably average from worthless to poor for cattle, 

 and from poor to fair for sheep. Livestock, however, particularly sheep, are 

 fond of the flowering tops and frequently pick these off and ignore the rest. 



The eriogonums seldom form extensive patches or become the dominant vege- 

 tation, but are characteristically scattered with greater or less frequency among 

 associated plants ; exceptions to this rule include the local concentration of 

 some annual species on depleted areas. 



A number of species, by reason of wide distribution, local frequency, or some 

 other factor, rate special mention. Nodding eriogonum (E. cer'nuwn), for 

 example, is often common in waste places and overgrazed areas on the plains, 

 foothills, and in canyons upward to the spruce belt. It ranges from Alberta 

 and Saskatchewan, to Nebraska, Kansas, New Mexico, California, and Oregon. 

 This annual usually grows from 6 to 12 inches high, and is much branched, 

 especially above. The small white or pinkish flowers are borne in numerous, 

 characteristically nodding, stalked clusters scattered along the branches of the 

 inflorescence. This species is negligible as a forage plant. 



Desert-trumpet (E. infla' turn) , sometimes called Indianpipe weed, is another 

 interesting annual, which ranges from Colorado and New Mexico to California, 

 and is common along washes and on mesas and desert areas. As the specific 

 name inflatum suggests, the tubular stems, naked except for the basal leaves, 

 are inflated and trumpetlike near their ends, and somewhat resemble a cigarette 

 holder. After the terminal, diffusely branched inflorescences fall off (often as 



