Nettleleaf horsemint, a tall, coarse, fragrant herb, up to 5 feet high, 

 perennial from rootstocks, is the most important western forage 

 species in the mint family. It grows in the mountains from western 

 Montana to eastern Washington, California, and New Mexico. Nettle- 

 leaf horsemint occurs chiefly in the ponderosa pine, aspen, and spruce- 

 fir belts in moist to somewhat dry, gravelly clay, clay loarn ? sandy 

 loam, and gravelly loam soils in meadows, brushlands, open hillsides, 

 glades, parks, and open stands of timber. Very commonly asso- 

 ciated species are bromes, bluebells, lupines, geraniums, snowberry, 

 and chokecherry. Usually it grows in scattered stands, rarely in 

 dense stands, although sometimes it is fairly abundant in moist, rich 

 soil in the aspen zone. 



Livestock graze the plant until the flower parts begin to drop. 

 Later in the summer only the foliage is eaten; but as the younger 

 leaves remain green for some time after seed maturity, nettleleaf horse- 

 mint is preferred in the fall to a number of other valuable forage 

 species. While all classes of livestock graze this species more or less, 

 it is eaten chiefly by sheep. Cattle graze it moderately, horses slightly. 

 For sheep its palatability varies from fair to very good, largely 

 depending on associated species (principally the presence or absence 

 of choice forage species), location, and season of use. In general, 

 its palatability is greater in the drier portions of its range, in southern 

 Idaho, Utah, Nevada, and the lava beds of northeastern California, 

 than, for example, in northern Idaho and the Sierra Nevada in Cali- 

 fornia. It is usually of greater value in browse, larkspur, and many 

 weed types than in the better grass associations. 



The flowers of nettleleaf horsemint bloom but a few days. The seed 

 matures late in August. The seed supply produced is relatively 

 small per plant and germination tests have shown that only about 

 one-fourth of the seed is fertile (viable). Under proper range man- 

 agement sufficient plants tend to mature seed, satisfactory reproduc- 

 tion is fostered, and vegetative increase is attained in the individual 

 clumps. 



A number of segregates of this species have been proposed, includ- 

 ing AgastacTie greenei, A. montana, A. neomexiccma, and A. pattidi- 

 flora, based largely upon slight differences in color, shape, and length 

 of the calyx teeth. For practical purposes, however, these are re- 

 garded in this treatment as synonyms of A, urtiti folia; in fact, some 

 of the more conservative botanists prefer to regard these as forms 

 of one variable species, A. ivrticifolia. 



The root system of nettleleaf horsemint is deep and extensive. 

 The slightly furrowed stems are purplish at the base and, like all 

 mints, are square in cross section. The numerous leaves are more 

 or less tapering at the apex, green on both sides, and hairless (glab- 

 rous). They vary in size from quite small to 2~y 2 inches wide and 

 31^ inches long. 



The name Agasfache is from the Greek agan (much) and stachys 

 (a head of grain, or a spike) and refers to the large and often 

 numerous spikes of flowers which the plants bear. The species name 

 urticifolia refers to the resemblance of the leaves to those of nettle 

 (Urtica). 



