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TDB' As the base of the hills is approached the vegetation turns mixed and _, afeedy, figures TDo' and ;D~1. This condition persists up to the base of the calcined clay and into the va3es beto-!e~n the ridges. The vegetation in these areas is'deminated by t;vo shrubs, t`,ao grasses and one forb, Table TD3. The grasses are the better forage. The "iithic entosoi" layer where the calcined clay outcrops supports an impoverished vegetation dominated by ponderosa pine, four shrubs and one forb, Table TD3, Figures TD72 and TD13. The shrub cover is quite good on north slopes, Figure TD13, but it is thin on Crest exposures. The mountain mahogany is an excellent browse plant. A total of 68 species of plants were identified at Da~rlson. 'these included t.•rc trees, 11 shrubs, 17 grasses and sedges and 38 fortis, Table TG4. The .list includes one tentatl4el~' identified as I echla, 4'lh;Ch ;S rare i ~O1:;i"ado (r'ootnote to Table TD4). Here, as elsewhere, the extended search required to assure that unique, rare or endangered plants e•~ere not present, could not be made. It should be pointed out, however, that calcined clay layers are not common. Furthermore, there is evidence elsewhere that underground fires nay encourane genetic changes in plants. The iithic entosol on the calcined clay must therefore be regarded as a potential habitat for rare or unique plants, even though none was found. Productivity of the range at Da~•rson ~;ras rated poor by Dr. ldai}ace Johnson. He estimated average yeild of -'orage plants at not more than 400 pounds per acre -'or the grasslands, excluding the shrub type on the iithic entascl. Each area Cf grassland taken Out o-" production therefore represents a present loss of about II cotid-days cf grazinc annually. The shrub (ands are important for trinter range., As these lands are being grayed in the summer, they likely are not beina used r"or ;rimer gra~;ng of livestock.