M6 IOWA ACADEMY OF SCIENCE Vol. XXVI, 1919 



Myrica californica. — Very abundant, making up a large part of 

 the tall undergrowth. Reaches a height of five meters. 



Picea sitchensis. — Plentiful, though less so than the next species. 

 The trees are well formed but small ; however, they increase in size 

 as well as in abundance as we go eastward. 



Piniis contorta.- — This is the most abundant tree. In many places 

 it forms by far the dominant species, and there are considerable 

 tracts where it occurs in almost pure stands. Places were noted 

 where the plant association just previously described passed quite 

 abruptly into one of these pine areas, and here appeared in strong 

 contrast the two extreme forms of development of this tree. Along 

 the exposed forest edge the trees were low and distorted with 

 relatively stout trunks and long, horizontal or depressed branches. 

 This is typical of P. contorta. A little farther back, where the 

 growth was dense and the effect of the wind scarcely noticeable, the 

 trees attained the tall slender P. murryana (Lodgepole Pine) form, 

 practically indistinguishable from that of the Canadian zone tree of 

 the Cascade mountains, except in the mode of weathering or splitting 

 and cleaving of the bark, the difference here being doubtless due to 

 differences in moisture, temperature, etc. The largest specimens 

 noted were perhaps thirty centimeters in diameter and fifteen to 

 seventeen meters in height. 



Rhododendron californicmn. — An abundant and conspicuous 

 shrub, here reaching the dimensions of a small tree. Specimens 

 seven meters in height were seen. 



Rubus spcctabilis. — A highly characteristic species of this section. 

 The straggling bushes, partly supported by surrounding vegetation, 

 attain a height of three to four meters. 



Spircea douglasii. — Plentiful in the more open places. Some- 

 times over three meters in height. 



Tsuga hctcrophyUa. — Moderately plentiful. The trees are small. 

 but increase in size and numbers eastward. 



Vaccin'mm micro phyllum. — Rather infrequent among the tall 

 undergrowth, but attaining nearly the maximum size of the species. 



Vaccinimn ovatum. — Abundant, forming a considerable part of 

 the tall undergrowth. The bushes are erect, strict and sparingly 

 branched, often five meters in height. The contrast between this 

 species as it appears here and on the wind-swept areas above 

 the beach is most remarkable. 



Where the forest is most dense low herbaceous vegetation i? 

 nearly wanting. The most abundant and generally distributed 

 species is perhaps Pteridiuin aqiiilinum var. pnhcsccns, which is 



