Nov., 1918] Recovery of Vegetation at Kodiak 



37 



the plants are still living, but after four years are only three 

 inches tall. (See page 36). The contrast offered by such 

 plants with grasses which have come up from the old roots (see 

 page 7) is too striking to need further discussion. The 

 importance of surviving plants in the revegetation cannot be 

 overestimated. Where for any reason none of the old plants 

 persisted, the ground remained as bare as when the ash first 

 fell, for no seedlings were able to start in such places. The 

 reason did not lie in the sterility of the ash, for as will be seen, 

 this can be overcome where the surface is stable enough to give 

 the young plants a chance. The trouble is that the ash, having 

 the consistency of fine sand, is kept moving so rapidly by the 

 wind that seedlings have no chance except in sheltered places. 



Photograph by R. F. Griggs 



ASH DRIFT LODGED BEHIND FIREWEEDS. 

 The drifts bear every appearance of snow banks. The fireweed endured such 

 burial for three years but then succumbed. 



ASH DUNES LIKE SNOW DRIFTS. 



One of the most striking examples of the effect of wind 

 action was in the plowed field above referred to. Here every 

 passing gust of wind picked up a cloud of dust, while the heavier 

 sand particles were swept along the ground. Volcanic ash is 

 composed of angular fragments of glass far sharper than 

 ordinary sand. The sand blast was thus very hard on all 

 plants exposed to it. The few weeds which escaped the plow 

 and came up through the ash in the open part of the field were 



