CONIFERS OF THE ROCKY MOUNTAIN REGION. 9 



high mountain form of the western larch. A very few people know 

 it as " woolly larch/' a name suggested on account of the woolly 

 young twigs. The book name "Lyall's larch," coined directly from 

 the technical name of the tree, seems not to have gained current 

 use. The common name alpine larch is very appropriate because 

 it refers to the tree's characteristic alpine habitat near timber line, 

 and may serve roughly to distinguish it from the closely related 

 western larch. 



Alpine larch was discovered on the Cascade Mountains 16 in 1860 

 by Dr. David Lyall, surgeon and naturalist to the International 

 Boundary Commission which surveyed and determined the boun- 

 dary between British Columbia and the United States from the Gulf 

 of Georgia to the crest of the Rockies. In 1863 it was technically 

 described and named Larix lyallii Parlatore, a name which has been 

 maintained for it practically throughout the 50 years this tree has 

 been known to science, but one other technical name, Pinus lyallii 

 Pari., now a synonym, having been applied to it during this time. 17 



DISTINGUISHING CHARACTERISTICS. 



Alpine larch usually is stunted in appearance, attaining a height of 

 from 30 to 50 feet and a diameter of from 10 to 24 inches. Exception- 

 ally large trees, sometimes found, are from 60 to 80 feet in height 

 and 3 feet or more in diameter. The long, broadly pyramidal, open, 

 pointed crown is often unsymmetrically developed, some of the 

 branches being very long and big. As a rule, the ends of the branches 

 turn upward, but frequently they droop consipcuously. In contrast 

 to the brittle branches of western larch, they are tough and withy. 

 A notable characteristic of the new shoots (PI. Ill, b) is their dense 

 coating of white, fine wool, which is retained, more or less, for two 

 seasons, and from which the tree gained the name of "woolly larch. " 



The trunks are clear of branches for only about one-third or one- 

 half the tree's height, and, as a result of exposure to strong winds, 

 are often crooked or bent. The bark of mature trees is rarely more 

 than seven-eighths of an inch thick. It is indistinctly furrowed, the 

 irregular, flat ridges of loose scales being of a deep purplish or reddish 

 brown color, while the smooth bark of the branches is an ashy gray, 

 as is that of young trees, on which the bark is usually unbroken until 

 they are 5 or 6 inches in diameter. 



16 Lyall, Journal of Linnsean Soc, VII, 143, 1864. Dr. Lyall does not say whether he found this larch 

 in the Oregon or Washington Cascades. 



1 7 Larix lyallii appears not to have been introduced into cultivation as yet either in Europe or in this 

 country. However, the very great difficulty of obtaining seeds, because the tree grows only in rough 

 mountainous sections not easily accessible, may partly account for this. The seeds are shed soon after 

 they are ripe, and to secure them the collector must be on hand just prior to this event. Whether or not 

 Larix lyallii can be grown successfully outside of the severe climatic conditions of its natural range is to 

 be determined only by actual trial. It has little of special beauty in form or appearance to commend it 

 for ornament over other native and exotic species now in cultivation, the chief interest in attempting to 

 grow it being its unique botanical characteristics. 



49432°— 18— Bull. 680 2 



