Vol. LIX. No. 2642. 
NEW YORK, SEPTEMBER 15, 1900. 
II PER YEAR 
l STRIPPING BARK FROM APPLE TREES. 
EXPERIMENTS WITH KNIFE AND SHEEP’S TOOTTI. 
The Effect Upon the Tree. 
“HIDEBOUND” TREES—During the last few 
years, several articles have appeared in different agri¬ 
cultural journals, advising the stripping of portions 
of the bark from old failing fruit trees, to renew 
their vigor and promote fruitfulness. Quite fabulous 
accounts have been given of the beneficial effects of 
such treatment on certain trees, and some of the rea ¬ 
soning applied to the problem is quite unique. Among 
those familiar with the practice, there seems to be 
some difference of opinion as to the purpose of such 
treatment. Certain persons claim that the idea is to 
renew the bark, which having become dry, hard and 
non-elastic, does not yield readily to 
the outward pressure of the growing 
trees, and retards growth both by pre¬ 
venting new wood from being laid 
down and by interfering with sap cir¬ 
culation. Trees in this condition they 
term hidebound. Others claim that the 
sole object is to induce greater fruit¬ 
fulness; the process of stripping by 
retarding the downward flow of elabor¬ 
ated sap, promoting the formation of 
fruit buds. It is thus analogous to 
ringing, girdling, etc. This practice, 
while it seems to be quite well known 
among the older fruit-growers, is 
scarcely mentioned by our horticul¬ 
tural writers. Two years ago an ex¬ 
periment was started at this Station 
to determine the effect of such treat¬ 
ment on apple trees. Two trees were 
chosen for this purpose; a Rambo 
(Fig. 221) and a Ben Davis. They 
were both trees of good size; the Ben 
Davis about 20 years old and the 
Rambo probably a few years older. 
The Ben Davis was growing in plowed 
land, and received regular cultivation. 
This tree was part of an old orchard, 
and had been left undisturbed when 
the rest of the orchard was grubbed 
out. It had commenced to decline, 
however. Branches were dying in the 
crown of the tree, and large patches 
of dead bark were showing on some of 
the main limbs. The Rambo was 
standing in sod. The earth around it 
had been dug up two years previous, 
and 30 pounds of raw bone meal ap¬ 
plied. The first year after the appli¬ 
cation of the fertilizer the tree made 
a very rank growth, and blighted 
quite badly. It has been free from 
blight since, and the growth has been 
very good for a tree of that age. 
CUTTING OUT STRIPS.—Both of these trees were 
operated on June 19, 1898. Strips of bark two to three 
inches wide, extending up the trunk and a few feet 
on to the main limbs, were removed. An interval of 
six or eight inches of undisturbed bark was left be¬ 
tween the stripped portions. The bark at this time 
of year peels readily, leaving the soft, smooth cam¬ 
bium exposed. These stripped places were carefully 
watched to note the effect of the stripping. On the 
Rambo tree, with the exception of two short spaces 
upon the limbs, all of the exposed cambium kept 
growing, and commenced to form new bark. The 
stripping on the Ben Davis was not nearly so suc¬ 
cessful. About half the exposed cambium lived. In 
two strippings, which had been made below dead limbs 
which had not been cut off, the cambium died; while 
in one made beneath where a large limb had been 
removed two years before the cambium lived. Wher¬ 
ever the stripped portion extended to the dead wood 
already mentioned as being in the tree, the exposed 
cambium never survived quite to the old line of de- 
markation between live and dead wood. The next 
year both trees were stripped as before, each strip 
being removed alongside of the strip of the previous 
season. There were no noteworthy differences be¬ 
tween the results of this and those of the previous 
season’s work. There was about one-fourth of a 
crop of apples on each tree; about the same both 
in quality and quantity, as other trees the same year. 
THE RESULT.—The Ben Davis tree was losing 
ground steadily; there were several dead branches 
and the dead portion in the trunk was extending 
On this account and for the purpose of making a 
careful examination, this tree was grubbed up in 
November, 1899, and the root, trunk and branches 
were thoroughly inspected. The heart wood of the 
trunk and many of the main branches was discolored, 
and had a sour, fetid odor. These discolored parts 
did not extend to the two outer annual rings, and 
there was no indication that the stripping operation 
in any way caused the trouble. See Figs. 222, 223 
and 224. The root was apparently sound and 
healthy. In every instance the wood laid down at 
the point where stripped was less than on the undis¬ 
turbed portion. 
WORK OF SHEEP.—An orchard on the college 
farm also gave some good data on this subject. It was 
composed of apple trees of various ages, and had 
been pastured to sheep during the Summer of 1899. 
These sheep had stripped the bark from a number 
of the trees, the extent of the injury varying from 
a few inches to a complete girdle. On the younger 
and more vigorous trees, almost without exception, 
the exposed cambium kept on growing, new bark 
being laid down immediately. The growth in each 
case was quicker, and the healing most perfect, 
where the trees were younger and the growth most 
vigorous. Here, however, as in the case of the Ben 
Davis, the growth under the stripped portion was less 
than where it had not been stripped, Figs. 225 and 
226. All of these trees were apparently healthy 
and making a good growth. Both in point of sea¬ 
son and variety the experiment was unfortunate for 
determining the effect of this practice on the size 
and quality of crop. The two trees 
experimented upon, Rambo and Ben 
Davis, are both free bearers, the 
Rambo usually bearing too much. In 
neither case is any artificial method of 
forcing fruiting necessary or advis¬ 
able. The season of 1898 was a total 
apple failure here, and 1899 was a par¬ 
tial failure; so the test as to the ef¬ 
fect on the fruit yield has not been 
satisfactory. Its benefits in this re¬ 
spect are problematical, but it might 
be advisable to try it with persistent- 
ly-barren trees. It would seem, how¬ 
ever, as though the best method would 
be first to try to determine the cause 
of such barrenness. If it were a 
young tree making luxuriant growth, 
and had passed the age when it should 
commence to bear without fruiting, 
stripping might be beneficial. Old 
trees beginning to fail from lack of 
nutrition would not probably be bene¬ 
fited by such treatment, but would 
probably be injured. Extra cultiva¬ 
tion and fertilization are the remedies 
which suggest themselves for such 
cases. If it is suspected that the 
hard resistant bark in old trees is con¬ 
stricting the growth, this pressure 
may be relieved by slitting the bark 
up and down the trunk with a sharp 
knife. We have no proof that such a 
hidebound condition ever exists. 
Sorauer is the only horticultural au¬ 
thority I have been able to find who 
mentions bark stripping. He gives a 
good description of the practice, which 
he states is used for forcing trees into 
fruiting. He further says the practice 
is dangerous. It certainly would bet¬ 
ter be used with discretion. 
THE BEST TIME.—In the Summer 
of 1899 tests were made to determine 
the best time for removing the bark. The trees 
used for this phase of the work were two Rambo 
standing in sod. They had received no cultiva¬ 
tion for years and while bearing freely, though 
rather sporadically, were not making much twig 
growth. They were strong apparently healthy trees. 
Beginning March 20 strips of bark were removed ap¬ 
proximately every 10 days until July 20. The re¬ 
sults were rather contradictory. The bark did not 
peel readily until May 1. In all strips removed that 
date it was impossible to remove the bark exactly 
down to the cambium. If the knife penetrated be¬ 
low the cambium the exposed wood of course died, 
while if some of the bast were left on the cambium 
such cambium continued to grow. The cambium ex¬ 
posed May 1 and 10 lived, while that operated on 
RAMBO APPLE TREE STRIPPED TWO SUCCESSIVE SEASONS. Fig. 221. 
