Jan., 1919] Effects of the Eruption on Vegetation 189 



HERBAGE INJURED LESS THAN TREES. 



Beneath the trees, the ground is for the most part absolutely- 

 bare. Wherever the ashfall amounted to three feet or more 

 nothing could come through. Apparently there were no surface 

 cracks as around Kodiak. At least no evidence of them remains, 

 and the ash near the volcano was so much coarser grained than 

 that deposited at a distance that "mud cracks" would hardly 

 be expected. Consequently, conditions were much less favor- 

 able for the penetration of the ash by the buried herbage. But, 

 although the herbage was almost completely smothered by the 

 ashfall, there is good reason to believe that it suffered less from 

 the eruption itself than did the trees. While the trees remained 

 exposed to the elements throughout the period of the eruption, 

 the herbs were quickly covered with a protecting blanket of ash 

 which shielded them from further injury. Where this blanket 

 was later removed by the agents of erosion, the smaller plants 

 have come up in their former profusion and are fruiting freely. 



This is true throughout Katmai Valley. And even on the 

 slopes of the volcano itself, every area bared of ash is occupied 

 by plants which survived the catastrophe. Wherever the ash 

 coveri?ig has been removed, the old herbage has sent up new shoots. 

 On "Prospect Point" for example, a high rocky hill 500 feet 

 up the slopes of the volcano, a few living plants were found 

 in 1916 including the following: Potentilla villosa (in flower), 

 Salix arctica, Salix glauca, Rhodiola rosea (flowering), Carex sp. 

 (flowering), Oxyria dignyia (flowering), Cerastium sp., Heuchera 

 glabra, Dryopteris droypteris, three species of grasses, Poly- 

 trichiim and another small moss. The particular species are, 

 however, of little importance for the list includes most of the 

 plants which happened to occupy the denuded area before the 

 eruption. With the living were the dead remains of only three 

 others, viz., Alnus sinuata, Diapensia lapponica and Silene 

 acaulis. On the lowland a few hundred yards farther from the 

 crater were found: Calamagrostis langsdorfii, (fruiting), Carex 

 sp. (fruiting), Equisetum arvense, Rubiis spectabilis, Sanguisorba 

 sitchensis, and Artemesia tilesii (flowering). It could be plainly 

 seen that many of these plants were new shoots coming from 

 old roots present before the eruption. At another place about 

 ten miles from the crater, where an upland bog happened to be 

 so located as to be cleared of ash, the following have reappeared: 



