April, 1919] 



Beginnings of Revegetation 



329 



abeyance. But Mr. Sayre is continuing the bacterial work, 

 having made further collections of soil for bacteriological study 

 during the summer of 1918. 



WILLOWS STARTING IN SOME PLACES. 



In more sheltered situations, seedlings of a number of species 

 are starting in many places. The most important of these are 

 probably the grasses, Deschampsia caespitosa and Calamagrostis 

 langsdorfii, (see page 326). With these are other herbaceous 





'aft': '" tf* ~- ■^'^^'\:h> *JL. '*-f*^f 



w*^ •.«•> 



Photograph by Robert F. Griggs 



YEARLING WILLOW PLANTS GROWING IN WATER-LAID PUMICE. 



The appearance of these plants in August, 1915, is shown on page 328. 



This picture was taken in August, 1916. 



species, including Artemesia tUesii, Campe barbarea, (see page 

 331), Polemonium acutiflorum, Epilobium alaskcB, (see page 327), 

 Mimidus langsdorfii and also the frutescent Sambiicus pubens. 

 There are also considerable areas where the ground is covered 

 with seedlings of willow, (Salix alaxensis, Salix barclayi, Salix 

 nuttallii and Salix bebbiana). (See page 328). Many of these 

 latter survived the first winter and made vigorous growth in 

 1916. They have not, perhaps, established themselves well 

 enough to justify the prediction that the pioneer growth over 



