15 
mixture, eau celeste, and ammoniacal copper carbonate on oats and 
corn. The experiments seemed to show that all but bordeaux mixture 
reduced the germination. 
Hitchcock and Carleton! report the effect of copper sulphate on corn. 
Solutions of 5 and 10 per cent strength were used, the seed being 
soaked for twenty-four, forty-eight, and seventy-two hours. It was 
found that seed soaked in the 5 per cent solution for forty-eight hours 
or in the 10 per cent solution for seventy-two hours gave less than 50 
per cent germination, while that soaked in the 10 per cent solution for 
twenty-four and forty-eight hours gave between 50 and 80 per cent 
germination. The effect was practically the same for wheat, lettuce, 
mustard, alfalfa, tomato, and castor bean seed. 
Brefeld,? in recent experiments, showed that corn smut can not be 
prevented by treatment of the seed, as the fungus can gain access to 
any meristematic tissue of the host and set up a local infection. 
In India? sorghum seed is commonly treated with 0.5 ounce of copper 
sulphate dissolved in water enough to cover the seed required for 1 
acre. Where such treatment is followed no smut is found. 
At the Mississippi Station‘ five tomato seeds each were planted in 
thirty boxes containing soil with 0.5 per cent of dry copper sulphate. 
The germination ranged from 0 to 52 per cent. The plants produced 
were weak and of a bluish color. The same boxes were seeded again, 
the seed in this case germinating well; however, the plants produced 
were weak and all soon died. 
G. McCarthy?’ claims that 1 gram of copper sulphate per liter of water 
will retard the germination of most seeds, especially those of leguminous 
plants, and that in most cases the germinative ability of one-third or 
more will be destroyed. 
Haselhoff® investigated the effect of copper on plants, and found that 
soluble salts are injurious to them when applied in solutions contain- 
ing 10 mg. of copper oxide per liter. In smaller quantity very little 
if any injury was done. He claims that copper salts are more inju- 
rious to oats and barley seed than to grass seed, and more so to corn 
than to beans. Wherever there was an abundance of lime in the soil 
the injurious action was to a considerable degree prevented. 
Vedrodi’ found that garden soils in his region contained an average 
of 9.06 to 0.08 per cent of copper oxide, and no effect could be noticed 
either on germination or on the subsequent growth of anything that 
was planted there, although on analysis the proportion of copper found 
1 Kans. Sta. Bull. No. 41. 
? Untersuchungen aus dem Gesammtgebiet der Mykologie, 1895, No. 11. 
3 Khandesh Expt’l Farm Rept. 1892, Mar. 31. 
4Miss. Sta. Rept., 1893, p. 56. 
5N.C. Sta. Bull. No. 108, p. 370. 
6Landw. Jahrb., 21, 1892, No.1 and 2, p. 263. 
7Chem, Centralbl., 1, 1894, p. 482. 
