16 The Ohio Journal of Science [Vol. XIX, No. 1, 



ash remains bare with only the beginnings of revegetation. 

 It should be possible by studying the transitions from one 

 condition to the other, and by examining the peat, to gain 

 considerable information concerning the sequence of events. 

 It is very much to be hoped that results of such a study may soon 

 be available. 



ASH POOR IN NUTRIENT SALTS. 



Before taking up the discussion of the details of the recovery 

 of vegetation at Kodiak, it will be advisable to consider the 

 chemical character of the ash. I find that there is a wide- 

 spread idea that this remarkable recovery is due to some 

 "fertilizing" property in volcanic ash which stimulates plant 

 growth. This idea owes its origin to the well known fertility 

 of soils derived from the weathering of volcanic rocks, especially 

 from basaltic lava flows. In the United States particularly, 

 the fertility of the soils derived from the great Columbian 

 lava flows of Oregon and Washington have been so much 

 advertised as to have influenced the thinking of many people. 

 Even so competent an authority as Russel says, concerning a 

 fall of volcanic ash in the west: "This last light shower of 

 dust * * * * added many thousands of tons of fertilizing 

 material to the region on which it was spread." 18 A little 

 reflection will convince anyone, however, that there is a vast 

 difference between a fresh deposit of raw ash and a soil derived 

 from the slow weathering of lava through perhaps a million 

 years. There was, moreover, a great difference in the initial 

 chemical composition of basic lava like the basalt of the Colum- 

 bian region and the acid ash deposited at Kodiak. Whereas 

 the one contains considerable quantities of the salts required 

 for plant growth, the other, as shown by the subjoined analysis, 

 is very low in such compounds,* having in fact practically 



18 Russel, I. C. Volcanoes of North America, p. 287. 



* Analysis made by Elton Fulmer, State Chemist of Washington for the United 

 States Department of Agriculture. Sample was collected at Kodiak and consisted 

 of all three layers mixed so as to give a fair average of the conditions encountered 

 by plant roots. 



Loss on ignition 0.65% Lime (CaO) 3.80% 



Silica (SiO 2 ) 72.16% Magnesia (MgO) 0.47% 



Ferric oxide (Fe 2 O 3 ) 2.85% Soda (Na 2 O) 3.86% 



Manganese oxide (MnO) 0.41% Potash (K 2 O) 2.43% 



Titanium oxide trace Sulphuric acid (SO 3 ) 0.20% 



Alumina (A1 2 O 3 ) 13 . 85% Phosphoric acid (P 2 O 5 ) 36% 



Remarks: The ash is highly magnetic; in all probability some, of the iron 

 present is magnetic. 



