CuLTi^RAL Experiments 



187 



TABLE XXII 



Cultures in Tailings Soils 



No. Pot culture Condition 



3887 Corn in sandy loam Distinctly striped 



3888 Corn in sandy loam Less distinctly 



and tailings striped 



3887 Beans in sandy loam Normal appearance 



3888 Beans in sandy loam Normal appearance 



and tailings 



3887 Squash in sandy loam Yellow and stunted 



3888 Squasli in sandy loam Normal appearance 



and tailings 



Cu 



in soil, 



per cent 



.027 



.047 

 .027 

 .047 



.027 

 .047 



Cu p. p.m. in 



tops 



28.00 

 19.00 



73.00 

 45.00 



roots 

 453.00 



163.00 



1523.00 



703.00 



Fig. 12. — Showing effects pf copper modified by tilth of soil. Strong growth, 

 lumpy mixture; weak growth, thoroughly mixed. 



Bean cultures appeared little affected by copper iu either 

 No. 3887 or No. 3888; but squash was distinctly damaged in 

 No. 3887, being yellow and stunted. The leaves of both cultures 

 of corn were paler than those of the check, but in soil No. 3887, 

 containing less copper, the leaves of corn were more distinctly 

 striped than in No. 3888. This is probably due to the sandy 

 character of No. 3887 with consequently decreased adsorptive 

 'action upon copper salts. Lumpiness in the heavier soil might 

 also account for a lessened toxic action, as indicated by an 

 experiment in which 0.1 per cent of copper in the form of pre- 



