THE NATIONAL NURSERYIMAN 
93 
hole cut ill the center to conform approximately to the size 
of the tree trunk, and a slit from the hole to the outer 
edge. Several sizes are put out for dilferent sized trees, 
and each of them has slits in the edge of the center hole, 
so that slight variations in trunk girth may be allowed 
for. In principle the protector is designed to prevent the 
newly hatched larvae from crawling beneath the surface 
of the ground to enter the tree. 
We have found that the protectors are somewhat difli- 
cult to apply and that they are rather hard to keep in 
place. The growth of the tree and the shaking by the 
wind tend to cause the paste to break loose from the tree, 
thus leaving an opening between the trunk and the pro¬ 
tector, consequently the etficiency of the protector is de¬ 
stroyed until it is re-sealed to the tree. The principle 
seems to be good, however, and our test is being con¬ 
tinued. 
Treatment Recommended by the Pennsylvania Sta¬ 
tion. The first steps in the control of peach borers 
should begin with the setting of the young orchard. Ex¬ 
amine each tree carefully and discard any that shows the 
slightest indications of the presence of borers. In the 
growing orchard the trees should be gone over twice each 
year, once as late as practicable in the fall and again in 
May. When examining the trees in the fall, the earth 
should be removed from about the crowns to a depth of 
several inches ,and where masses of gum are present a 
careful search should be made for the borers with the aid 
of a sharp strong knife and a piece of pliable wire. Care 
should be taken not to cut across the grain of the wood 
more than is necessaiy. It is well, when removing the 
masses of the gum from about the crowns, to scrape off 
the accumulations carefully and throw them away from 
the tree a distance of several feet. By so doing some of 
the very young larvae which have not yet penetrated the 
bark may be destroyed, as they are unable to travel more 
than a few inches and they soon die. It must not be 
I bought that all of the small white worms often found in 
the gum are young borers, however, as certain scavenger 
flies of the species, Mycetophila persicae, are known to 
deposit their eggs in this gum, and the resulting maggots 
somewhat resemble young peach borer larvae. 
The bases of the trunks should not be left exposed 
longer than is necessary at this time. The soil should be 
slightly mounded about the trunks to serve as winter pro¬ 
tection and to aid in healing up the freshly cut surfaces. 
Nothing will be gained by the application of any wash at 
this time. 
When the search for borers is made in May, the above 
operation should be repeated. At this lime the bases of 
the trunks should be left exposed for a week or so to 
toughen the bark, after which lime-sulphur solution 
should be applied with a spray pump at high pressure 
from the exposed crown up to a distance of two feet or 
more on the trunk. In this locality, to be most effective, 
the application should be made about the second week in 
June. When the wash has thoroughly dried, the soil 
should be mounded up to a height of 6 or 8 inches. 
In a series of experiments carried on by the Pennsyl¬ 
vania Station during the three year period from 1909 to 
1912 and again started in 1915, it was found that lime- 
sulphur solution in pure undiluted fonn can be used with 
entire safety on the trunks of peach trees. Commercial 
concentrated material ti'sting as high as 133 sp. gr. was 
used, and a better coating maintained than was possible 
by the use of the diluti'd solution. Some dilution may be 
jireferable, howevei', in commercial practice, though it 
should not reduce the density lower than about l.Ofi. 
Doctor Smith strongly recommends the addition of one 
pound of lead arsenate jiaste to each 5 gallons of the lime- 
sulphur solution with the idea in mind of poisoning the 
young larvae when they attempt to cut into the tree. On 
the contrary, extensive experiments carried on at the 
Cornell Station by Professor Slingerland showed prac¬ 
tically no favorable results from llu' usi; of arsenicals in 
combating this borer. 
In addition to this, ri'cent invi'stigations by tin' Penn¬ 
sylvania Station, of sei'ious injury to peach trees in sev¬ 
eral jiarts of the state, have indicati'd that jiositive injury 
may sometimes result from the use of arsenate of huid in 
combination with lime-sul|)hur on the trunks of peach 
trees. Chemical analyses of the diseased bark have 
shown that arsenic is present in injurious amounts in the 
affected tissues, and this jiarticular type of injury has 
always been confined to the treated areas. 
It is possible that the (juality of the arsenate' has some¬ 
thing to do with the occurrence of the injury, but in view 
of the present indications, it is evidently doulitful whethi'r 
important amounts of any of the comme'rcial arsenates 
can be used with entire safety in this way. 
It is also possible that a great deal of the injury as¬ 
cribed to lime-sulphur and arsenate of lead combinations 
is due to winter injury. This type of injury is esjiecially 
likely to occur when the soil is not properly filled in about 
the trees after the search for borers has been made. Fur¬ 
ther experiments on lime-sulphur arsenical injury have 
already been started. 
The purpose of the mounding is to cause the females to 
oviposit well up on the trunk, so that if they lay their eggs 
on the tree in spite of the repellent coating, the resulting 
borers can be much more easily reached and destroyeil. 
Furthermore, since the adult moths are very shy in their 
habits, many of them will seek other hosts upon which to 
deposit their eggs rather than those in the exposed situa¬ 
tions at the tops of the mounds. 
The coating of lime-sulphur should be maintained on 
the trunks until the end of the egg-layiiig season. Cen- 
erally about two additional applications of the same 
strength material, ajiplied in the same way, except¬ 
ing that the mounds should not be removed, 
will serve to maintain the coating very salisfacloi’ily. 
Under ordinary weather conditions the si'cond apj)lica- 
tion might well be made about July 1, and the Ihiril about 
August 15. These tinu's may of course be varied in ac¬ 
cordance with the condition of the coating pi-eviously ap¬ 
plied. 
The above recommended course of procedure, embody¬ 
ing a combination of the juotective wash, mounding, and 
old digging-out methods has proved to be one of the most 
practicable and satisfactory at this Station, and the same 
treatment with slight modifications has bi'cn recom¬ 
mended above all others at the New Jersey Station. 
Many practical fruit growers throughout the state have 
come to use this system of control, or to use others vi'iy 
similar to it in its essential points, and so far the results 
obtained have been very satisfactory. After a year or 
