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very readily on neglected pasture lands and other areas which 

 have previously borne forests. This we may see demonstrated 

 in tracts devastated by forest fires, though such cases are found 

 mostly in mountainous regions. The conditions above described 

 are found mainly in the northern part of the Willamette valley. 



The valleys of streams tributary to the Willamette which head 

 in the Coast Mountains are flanked in their upper parts by forests 

 of much the same character as those described above. Along 

 these streams it is noticeable that the vegetation is much the 

 same as that which characterizes the river bottoms already de- 

 scribed but along with Thuya and Abies we find Tsuga hctcrophylla. 

 In the undergrowth the occurrence of Rubus spcctabilis is occa- 

 sionally marked. Among the more prominent herbaceous plants 

 Micrampelis Oregana is often very conspicuous, covering shrubs 

 and small trees to a height of twenty feet or more. 



The vegetation of the Coast Mountains is a heavy forest growth, 

 mostly of Pseudotsuga with a considerable sprinkling of Tsuga and 

 Thuya ; of the deciduous trees there are species of Acer, especially 

 A. circinatum, and Alnus. In the older burned areas, Alnus springs 

 up plentifully along the water courses and every small ravine 

 with springy soil is marked by a line of alders. Comparatively 

 little of the second growth in these "burns" is evergreen; 

 willows and alders are by far the most conspicuous. Most of 

 such burned areas have very little forest growth at all to show 

 in place of the once magnificent growth which covered the moun- 

 tain tops and the bleached remains of which are still standing or 

 lying upon the ground. In such places the most conspicuous 

 growth is the ubiquitous Pteridium aquiliuum which often ex- 

 cludes everything else except shrubby plants such as Rubus Nut- 

 kanus and species of Vacciuium. 



That section of the state which lies between the summit of the 

 Coast Range and the Pacific Ocean is much more abundantly 

 supplied with moisture than the Williamette valley and parts 

 farther east. The mean annual rainfall in this belt is not far from 

 80 inches. On the eastern slope of the range it is much less, 

 about 60 inches, diminishing to about 50 inches in the middle of 

 the valley. In some places on the coast the mean precipitation 



