16 



YOSEMITE NATURE NOTES 



All oaks ore wind pollinated. Thus 

 these trees are rendered conspicuous 

 in the early spring when, at about the 

 time the leaves ore beginning to de- 

 velop, they are festooned with numer- 

 ous loose, pendent, tassel-like stam- 

 inate catkins which bear the abund- 

 ant pollen. 



Mature specimens of the California 

 black oak are from 75 to 80 feet tall 

 and one and one half to three feet in 

 diameter. It is a moderately long- 

 lived tree, attaining an age of about 

 300 years. Large trunks of old trees, 

 however, are rarely sound. These are 

 generally characterized by decayed 

 centers and are often broken at the 

 top. Such specimens often furnish 



nesting sites for California wood- 

 peckers and occasionally one will 

 find a dead tree whose trunk and 

 larger branches serves as a "storage 

 bin" for these birds. In such instances 

 these trunks are studded with holes 

 in which acorns hove been tightly 

 wedged. 



Another feature of interest relative 

 to the California black oak is the 

 abundance of mistletoe (Phoraden- 

 dron villosum) found in these trees. 

 This, a parasitic plant, appears as 

 loose, bushy clusters, one to three feet 

 in diameter, among the branches. It 

 is particularly noticeable during the 

 winter when the tree is barren of 

 foliage. 



CANYON LIVE OAK 

 Quercus chrysolepis Liebm. — Beech Family (Fagaceae) 



This tree is also known as the 

 golden cup oak because of the hand- 

 some acorns, one-half to one and 

 one-half inches in length, which are 

 characterized by scaly cups densely 

 covered with bright yellow wool. The 

 acorns mature at the end of the sec- 

 ond year, and while a few are pro- 

 duced annually, large crops are 

 common only at infrequent intervals. 



Several additional features render 

 it of particular interest. It is one of 

 the evergreen broadleaved trees of 

 the Park and the leaves, which ore 

 alternate on the branches and oblong 

 in outline (about three inches long) 

 persist for three or four years. They 

 have a thick, leathery texture, are 

 smooth and yellow-green above, and 

 when young are covered with yel- 

 lowish down on the underside. They 



vary considerably in size and ap- 

 pearance on trees of different age — 

 in fact occasionally on parts of the 

 same tree. Leaves of larger trees or 

 older branches are generally smooth 

 along the margin but young speci- 

 m.ens, particularly vigorous shoots, 

 bear foliage that has distinct spiny 

 edges not unlike holly in appearance. 

 This feature causes many park visi- 

 tors to mistake young canyon live 

 oaks for holly — a plant not found in 

 the Yosemite region. 



Mature specimens are generally 

 from thirty to sixty feet tall with a 

 short, heavy trunk two to three feet 

 in diameter characterized by dark, 

 flaky bark. Thick, heavy branches 

 produce a wide spreading crown. 

 However, this tree varies widely in 

 size. In exposed locations at the 



