320 The Ohio Journal of Science [Vol. XIX, No. 6, 



The effort has been to locate them in such a way that anyone 

 can find them and carry on the study, if for any reason the 

 writer should be prevented from continuing it.* Beside these 

 formally established stations, there are many other localities, 

 not susceptible of such precise location, which the writer expects 

 to study repeatedly as opportunity presents. In the short 

 time that has elapsed since the beginning of the work, changes 

 at these stations for the most part have been small, so that the 

 progress in revegetation here reported has been worked out 

 from observation of the general conditions in the valley. But 

 as time goes on, repeated records of conditions at the fixed 

 stations and other localities photographed will furnish a more 

 and more valuable record of progress, which finally will give us 

 an understanding of the factors controlling the revegetation 

 of volcanic deposits under the climatic conditions obtaining, 

 and of the succession of plants in the process. Meanwhile, 

 laboratory studies of plant growth in the ash have been made 

 with samples brought back to the United States for the purpose. 

 These, besides supplementing and aiding in the interpretation 

 of the field observations, are of some interest in themselves. 



CONDITION OF SURVIVALS. 



The agents of revegetation consist of : (a) Surviving woody 

 plants which protrude through the ash. (b) Herbage which 

 has come up in places cleared of ash. (c) Seedlings starting in 

 the deposits. The effects of the first two categories on the 

 mainland may be dismissed with very brief discussion. The 

 poplars, birches and alders have not recovered sufficiently 

 to become of any consequence in revegetation, except as 

 helping in places to maintain a windbreak under which new 

 plants can start. None of them were found in fruit, although 

 a few seedlings of poplar were observed in one place. But the 

 larger willows, {Salix alaxensis, Salix harclayi, Salix niittallii), 

 have in places almost completely recovered and have begun to 

 produce seed abundantly, which bids fair to become an impor- 

 tant factor in revegetation. 



The resurrected herbage, though of great interest as showing 

 the possibilities possessed by plant life of surviving a violent 

 eruption, is of minor importance in the revegetation of Katmai 



*For a detailed discussion of the problems encountered in establishing the 

 vegetation stations see the first paper of this series, pp. 24-31, on p. 174. 



