Coal Mine Basin Research Natural Area

Vale District , BLM

Northern Basin and Range Ecoregion

Cell(s):

• Big sagebrush-spiny hopsage-budsage mosaic on ash
• Annual forb communities on exposed ash beds

Access by road south of US 95 in Idaho, but only in spring and summer and/or when dry

The 306 ha Coal Mine Basin RNA lies in eastern Malheur County near the Oregon/Idaho border between Jordan Valley, Oregon, and Marsing, Idaho. The extensive and colorful ash beds in Coal Mine Basin have highly scenic vistas, fossils of plants and vertebrate animals, as well as diverse plant communities. The RNA was designated to protect two types of plant communities on ash (Artemisia tridentata/Grayia spinosa/Artemisia spinescens and annual forb communities) and two special status plant species: smooth mentzelia (Mentzelia mollis) and Cusick's chaenactis (Chaenactis cusickii). The area has been recognized by BLM offices in both Oregon and Idaho as representing excellent examples of typical Succor Creek ash habitat for a full complement of common and rare species occurring on ash formations, in addition to the special status species. The climate is characterized by hot dry summers and cold, most winters. Average annual precipitation is 20 to 25 cm. Elevation ranges from 1280 to 1370 m. Soils derive from ash and basalts, both of volcanic origin. Disturbances include past and current livestock grazing, roads and recreation trails. The RNA has a high potential for the occurrence of hot springs and epithermal-related gold/silver/mercury deposits and zeolite, a moderate potential for the occurrence of geothermal resources and oil and gas, and a low potential for the occurrence of all other leasable and locatable minerals.