THE INJECTION OF CHEMICALS INTO CHESTNUT TREES 3 
ference being that it is an unusual (extraradicate) instead of the usual 
(radicate) current. The duration of this created second sap movement 
does not exceed five days. The most intensive absorption takes place at 
the beginning, gradually diminishes, and ceases entirely in from three to 
five days. He believed this diminution and cessation due to the obstruc- 
tion of the vessels. Shevyrev found that the weather greatly influenced 
the rate of intake; he made a record of the hourly intake of an injected 
grape vine and of the weather for a period of three days, which showed that 
the consumption at night was less in quantity than that in the day, regard- 
less of the weather. 
Shevyrev's experiments were made primarily for the purpose of destroy- 
ing such insects as injure plants by burrowing beneath the bark. He be- 
lieved, however, that fungous diseases could be cured by the same method. 
Shevyrev did not continue his experiments. The last paper (11) he 
published on the subject describes and criticizes the injection experiments 
of some Russian workers who had been treating diseased trees. He speaks 
of the experiments of K. K. Reshkv or K. Reschko in the Crimea, to which 
no other reference could be found by the present writer. Reschko treated 
in 1901, according to Shevyrev, a thousand trees suffering from chlorosis 
by introducing iron sulphate into canals cut in the bases of the diseased 
trees. The distribution of the substance was found to be irregular, so 
that individual branches were found to be uninjected. 
Pachassky (12), in a governmental report of 1903, Reported favorably 
on the injection of iron sulphate either in powder or in solution in the treat- 
ment of diseased fruit trees. 
C. A. Mokrjetsky (S. A. Mokrzecki or Mokrzhetski) (13), in governmental 
reports of 1902 and 1903, tells of injecting more than 500 trees, the method 
of injection being analogous to Shevyrev's. Diseased apple trees were 
cured with iron sulphate, gummosis of apple, pear, and other trees with 
I percent salicylic acid. He injected ''nutrient solutions" into frost bitten 
trees, which recovered rapidly after treatment and grew three times as 
much as the untreated trees. Another article (14) ''Uber die innere Ther- 
apie der Pflanzen" explains his work in more detail. The two methods of 
injection used are explained. One of them consists of inserting the dry 
salt in holes bored in the tree trunk. These holes are then closed with 
grafting wax. In the other method solutions are injected. The hole 
made in the trunk for the purpose of injecting is bored with a brace and 
bit which passes through a metal tube embedded in the tree. A side out- 
let in this tube is connected by a rubber tube with a jar containing the solu- 
tion to be injected. As the hole is bored by the brace and bit the solution 
passes into it, thus shutting out the air from the wound. Diseased trees 
were ilijected with copper sulphate, calcium cyanide, and arsenic in i/ioo 
percent concentration, with inconclusive results. Iron sulphate in 0.05- 
0.25 percent solutions (amount injected not stated), or the dry salt, 12 
