Great Basin: Oregon District. 569 
(Opulaster) pauciflorus, Ceanothus sanguineus, Rosa gymnocarpa. At a higher altitude, the under- 
shrub is a huckleberry Vaccinium macrophyllum. These pine forests are seldom pure except at 
low elevations. In moister situations at higher altitude the red fir Pseudotsuga Douglasii becomes 
associated with the pine, until according to PırEr, with increasing altitude the forest becomes 
similar to that on the mountains of the humid Pacific side of Washington and Oregon. 
The grasses of the upland thickets in the Blue Mountains of Oregon are 
Poa pratensis, Trisetum subspicatum, Danthonia californica, Melica subulata, 
Elymus glaucus, Carex Geyert, 
The principal facies of the Sage Formation: consists of the scattered 
clumps of Artemisia tridentata, associated with A. arduscula, A. cana (in the 
mountains). A. Zridentata is the black sage of the mesas and foot hills and 
takes the place of creosote bush ZLarrea mexicana and the Cactaceae of the 
deserts to the southward. With it is sometimes associated Artemisia spines- 
cens while Atriplex confertifolia, A. Nuttallü, Grayia spinosa, Eurotia lanata 
are also elements in the sage formation. 
The rolling hills in the tie country are covered with a luxuriant growth of Festuca 
ovina, Agropyrum spicatum (= A. divergens), r Wheeleri, Poa Sandbergii, while elsewhere occur 
Wyethia nn srchlie sagittata, B. Careyana, Bigelovia (Chrysothamnus) graveolens 
associated with Agropyrum spicatum and in places forming pure ErTeu Artemisia 
rigida = oecurs in pure associations.. — Still another association is composed of Artemisia 
rigida, uscula, Eriogonum dichotomum, E. sphaerocephalum, E. thym a Tetradymia 
canescens,  kidlbe rtia incana and Gilia pungens. The herbaceous vegetation consists of Gayo- 
phytum ramosissimum, Lygodesmia juncea, Agropyrum spicatum, Stipa 'Thurberiana, Festuca 
microstachya, Poa Sandbergii. 
Bunch grass Formation. The bunch grass prairies constitute a strip of 
varying width Iying between the sage brush formation and the yellow pine 
groves above. The soilis a black, clay loam, free from grit. These prairies are 
treeless and excepting along streams and by springs or on north hillsides, 
shrubs are rarely seen according to PIPER’). Of the herbaceous vegetation the 
bunch grass Agropyrum spicatum and June grass (Poa Sandbergüi) are abun- 
dant together with Zupinus ornatus, L. sericeus, L. Wyethü, Balsamorrhiza 
sagittata, Helianthiella Douglasti, Gaillardia PRETER Geranium incisum, Lepto- 
taenia multifida and in moister places Irıs missouriensis, Wyethia amplexi- 
caulis. 
he grasses in the Blue Mountains of Oregon are in the open places Poa nevadensis, Poa 
ee P. Sandbergii, P. Buckleyana (P. tenuifolia), Festuca ovina, Agropyrum spicatum (= 
divergens), Koeleria cristata, Bromus marginatus, Elymus (Sitanion) longifolium, Elymus conden- 
satus, ra caespitosa, Stipa viridula with Trifolium plumosum on the bare rocky slopes 
the open country 
Camass Meadow Formation. This formation is situated. in depressed areas 
more moist than the upland country. Here grow in the greatest profusion 
various grasses, interspersed with brillinatly colored flowers, such as | 
esculenta. 
ı) Flora of Washington. Contributions United States National Herbarium XI: 48. 
