184 



NATURALIST'S GUIDE TO THE AMERICAS 



Sub-Alpine forest 

 Alpine meadow 



The largest single area is known 

 locally as the "high desert." This area 

 is characterized by the sagebrush and 

 the rabbit brush {Chrysothamnus spp.) 

 on the slopes and well drained bottom 

 lands. Extensive alkaline lake beds, 

 river bottoms, and poorly drained flats 

 are characterized by the dominance of 

 the greasewood {Sarcohatus vermicula- 

 tus) and saltgrass (Distichlis spicata). 

 Sage brush may be associated with the 

 above plants in the transition zone. 

 Originally the western wheat grass 

 {Agropyron spicahim) and other bunch 

 grasses grew abundantly throughout the 

 entire desert area. The overstocking of 

 this sagebrush desert has largely de- 

 stroyed the grass as an abundant associ- 

 ate plant. The main desert area lies 

 south of the Blue Mountains and east of 

 the Cascade timbered slopes. It ex- 

 tends northward to the bunchgrass 

 prairie on the upper reaches and down 

 the river canyons to the Columbia. 

 Extensive desert lands also lie along 

 the Columbia in Gilliam and Umatilla 

 counties and in Baker county. The 

 sagebrush desert is called the Great 

 Basin Microphyll desert by Livingston 

 and Shreve although it extends beyond 

 the physiographic limits of the Great 

 Basin. Lava outcrops as "rim rock" in 

 frequent places where erosion has cut 

 through the great lava outpourings. 

 Along streams and under the rim rock 

 may be found various herbs and shrubs 

 that require more soil moisture. Con- 

 spicuous among these plants are the 

 western choke cherry (Primus demissa), 

 service berry (Amelanchier), squaw cur- 

 rant (Ribes cereum), golden currant 

 (Ribes aureum), mock orange {Phila- 

 delphus lewisii), willows and others. 

 Within the area of the desert plateau 

 and in Klamath County are large lakes 

 and marshes, which range from fresh to 

 alkaline. The lake borders and marshes 

 of the fresher waters are characterized 

 by the tule (Scirpus validus), cattail 

 (Typha lalijolia), water hemlock {Cicuta 

 occidentalis) and others. 



Between the high desert and the tim- 

 bered area on the south slope of the Blue 

 Mountains and other similar climatic 

 situations is a transition belt of western 

 juniper (Juniperus occidentalis), moun- 

 tain mahogany (Cercocarpus ledifolins), 

 and antelope bush. 



Perhaps the largest juniper forest in 

 the world is found as a transition be- 

 tween the sagebrush desert on the south 

 and the bunchgrass prairie on the north, 

 and lying between the Cascade and Blue 

 Mountains. Sagebrush and also an- 

 telope bush, are abundantly associated 

 with the juniper. Originally the west- 

 ern wheat grass and other grasses were 

 abundantly found in this area. 



The present wheat growing sections 

 of eastern Oregon were originally bunch- 

 grass prairie. It lies mainly on the high 

 rolling lands to the north of the Blue 

 Mountains. Small remnants of this one 

 time extensive prairie may be seen in 

 protected places. Western wheat grass 

 is the dominant grass. More or less 

 abundantly associated with it are the 

 prairie June grass (Koeleria cristata), 

 and other species of Agropyron, lupines, 

 prairie sunflower (Balsamorrhiza 

 sagittata), geranium, and others. 

 Stream borders are characterized by the 

 alder {Alnus tenuifolia), hawthorn 

 (Crataegus brevispina), snowberry, sym- 

 phoricarpos and clematis. 



Within the Blue Mountains proper and 

 on isolated peaks and small chains, 

 where the altitude may be responsi])le 

 for the supply of sufficient moisture, the 

 slopes are timbered. Western yellow 

 pine is the dominant tree throughout all 

 of the lower mountain slopes. The 

 same may be said for the east slope of 

 the Cascade Range and the Mountains of 

 Klamath county. Yellow pine may be 

 intermixed with sugar pine (Pinus 

 lambertiana) and a few other scattered 

 conifers to the south and with western 

 larch (Larix occidentalis), and Douglas 

 fir to the north. Western white pine, 

 lodgepole pine, Engelmann spruce, 

 white fir, alpine fir (Abies lasiocarpa), 

 and other conifers are found in increas- 

 ing abundance with the rise in altitude 



