6 Wyoming Experiment Station. 



are mere scales which are opposite (in four ranks), thickened 

 and closely appressed, thus forming a coating over the short 

 slender twigs. The berries are usually very numerous and of 

 a light green color when young, but of a bluish color at the end 

 of the second season when mature. This juniper is common in 

 the foothills more or less throughout the state, being very com- 

 mon on rocky hillsides and in canons. 



Desert Juniper (Juniperus Knighti Aven Nelson). 



Very similar to the preceding, but more bushy in form and 

 usually branched from the base. Its twigs are somewhat thick- 

 er than those of the Rocky Mountain juniper, and its scale- 

 like leaves are disposed in only three ranks. The berries are of 

 a blue-green color and with slightly projecting points on the 

 surface. It occurs in the desert region of southwestern Wyo- 

 ming, where its scraggy clumps may be seen in places on the 

 hills and bluffs otherwise devoid of trees or tree-like growths. 



WILLOW FAMILY. 

 (Salicaceae). 



The cottonwoods, the poplars and the aspen, as well as the 

 willows, are all included in this family. The American aspen 

 and four cottonwoods are native in the state, and a score or 

 more of willows occur within our borders. 



WILLOW. 



(Salix). 

 Willows are very prevalent and abundant in the state. They 

 are moisture-loving plants, familiar to everyone, occurring on 

 all our streams and very common in the mountains. Their 

 male and female flower clusters or catkins, which are usually 

 erect, are borne on different bushes. The male plants of some 

 of the species are quite handsome when covered with the yellow 

 catkins in early spring. The minute greenish capsules of the 



