294 
Journal of Agricultural Research 
Vol. VIII, No. 8 
and became paler and narrower until they disappeared. Where the 
stain was used with the arsenite, it was the same in character as where 
used alone, but was always much narrower than the dead streak sur¬ 
rounding it and usually shorter. Also, several side limbs were more 
or less injured by the arsenical, but contained no visible trace of the 
blue. In no case did the blue extend into living wood or bark. 
These results would suggest that the solutions absorbed by the 
wounds are not carried very far beyond the dead portions. 
INJURY AS AFFECTED BY CHARACTER OF WOUNDS 
Some questions arise as to the relative importance of wounds of differ¬ 
ent character. Are small abrasions sufficient to make injury possible? 
Does a wound just through the periderm admit the arsenic as freely as 
one extending to the cambium or into the sapwood ? When do wounds 
like those made by pruning become sufficiently closed to keep out the 
solution ? 
From a study of Table II it is evident that even a very slight rupture 
of the periderm is sufficient to make possible severe injury to the limb 
if the arsenical is applied continuously in a moist state (io, p. 86). 
So far as these few tests go, we may infer,, however, that the chemical 
is absorbed less rapidly if the wound is superficial than if it extends 
to the cambium. If, however, the slower injury, like that through the 
superficial wound in No. 3, results in a girdling of the limb, it is just as 
surely fatal to the portion above as though absorption were more rapid. 
In comparing the injury through wounds made by cutting off twigs and 
branches with that through wounds made by cutting out a small piece 
of bark to the cambium, we find that sometimes the injury is worse 
through the former and sometimes through the latter. On an average, 
there is not a great deal of difference. 
Table II .—Results of wounding and treating branches of Early Strawberry apple on 
August 21 , ign, with 5 gm. of Baker's copper aceto arsenite, to show the relative’injury 
through wounds of different size and character • 
No. 
Diameter 
of treated 
branch. 
Wound under bandage. 
Extent and'character of injury. 
Inch . 
1 
K 
Branch X inch cut off. 
Streak half around branch runs down from wound 
1 foot and up 3 feet to the tip. 
2 
X 
One-fourth inch square of bark re¬ 
moved to cambium. 
Streak half around branch runs down 7 inches from 
wound and up 4 feet nearly to the tip. 
3 
X 
One-fourth inch square of outer cork 
removed. 
Streak half around branch runs down from wound 
2 inches and up 3 inches; 
4 
X 
Transverse cut through bark to cam¬ 
bium on one side. 
Girdled under bandage, except for a small strip on 
side opposite wound. 
Streak from wound runs down 7 inches and up 20 
• inches. 
5 
X 
Radial cut i inch long through bark 
to cambium. 
6 
X 
Five fine needle pricks through bark. 
Entirely girdled tinder bandage. Streak runs 
down s inches to main limb and up nearly to tip, 
2H feet. 
7 
X 
Old pruning wound... 
Injury extends r inch up and 1 inch down from 
wound with little at the sides. A few lenticel 
spots. 
8 
x. 
Unwounded. 
Numerous lenticel spots % inch or less in diameter. 
9 
X 
Numerous lenticel spots inch or less in diameter. 
Two small spots around latent buds. 
