226 
PARK AND CEMETERY. 
machines, however, if attached to a ‘'solid 
stream” nozzle would give a much lower 
pressure. 
In “mist” spraying a nozzle with a fine 
hole which is usually fitted with some 
mechanical device for breaking up the so- 
lution into a mist is used, while in "solid 
stream” work the solution is delivered from 
an open bore nozzle with sufficient force to 
break it up thoroughly into a fine mist-like 
spray after attaining its greatest height. 
During the early stages of “solid stream” 
experiments nothing above 200 pounds 
pressure on a J^-inch nozzle was attempted. 
From a series of tests made recently, one 
manufacturer of high power sprayers now 
recommends that at least 225 pounds per 
square inch nozzle pressure be used, to 
which must be added the head loss due to 
hose friction to get the proper initial 
pressure. 
WINTER WORK 
The cutting of the locust tree for all 
purposes, including thinning operations and 
for private commercial use, should be done 
between the first of October and the last 
of March. To destroy the locust borers 
before they enter the wood, the removal 
of the bark from all desirable portions of 
the trunks of the trees felled is important 
and necessary. Tops and thinnings should 
be burned. 
The yellow striped, long horned, winged 
beetle that produces the devastating borer 
is found from August to October on trees 
and the flowers of the goldenrod. During 
this period eggs are deposited in the crev- 
ices of the bark of growing trees and the 
young borers, after being hatched, pass the 
winter there and in the spring bore 
through the bark to the heart of the tree. 
The injury to the trees consists of 
wounds in the bark and sapwood, which if 
sufficiently severe and repeated year after 
year, result in a worthless growth or the 
death of the timber affected. The numer- 
ous worm holes in the wood also reduce its 
commercial value. 
The presence of the insects in injurious 
numbers is indicated at this season of the 
year by the frequency of the adults on the 
goldenrod flowers and on the trees. So 
extensive has the damage of this pest been 
in some sections of the eastern states and 
the middle west that it is now considered 
unprofitable to grow the tree for either 
shade or timber. One important reason for 
holding this borer in check is to prevent 
its extension into the far west and other 
sections which are at present free from it. 
Experiments have demonstrated that the 
grubs may be killed by spraying the trees 
and branches with a strong solution of 
kerosene emulsion. This should be done 
earlier than November and not later than 
In ordinary municipal work the lines av- 
erage about 500 feet, while in wooded areas 
for practical work they are often extended 
to 1,500 feet. In solid stream forest work 
it is often found necessary to raise the 
initial pressure on such lines to above 350 
pounds per square inch, because with a 
lower pressure after it has suffered the loss 
due to hose friction the solution is not de- 
livered with sufficient velocity to break it 
into a fine mist-like spray after attaining 
its height. 
Some sprayers maintain that the elm leaf 
beetle can be held in check only by the 
“mist” method as it was generally supposed 
that the under side of the foliage had to be 
sprayed. Others contend that if a leaf is 
sprayed either top or bottom while the adult 
beetle is feeding, the results are satisfac- 
tory and the spraying cost reduced. 
TO DESTROY 
March, because this spraying when the 
trees are in leaf will destroy the foliage 
and check growth. 
This emulsion may be prepared as fol- 
lows : 
Kerosene Emulsion (Soap Formula) 
Kerosene 2 gals. 
Whale-oil soap (or 1 qt. soft soap) lb. 
Water 1 gal. 
The soap, first finely divided, is dissolved 
in the water by boiling and immediately 
added boiling hot, away from the fire, to 
the kerosene. The whole mixture is then 
agitated violently while hot by being 
pumped back upon itself with a force 
pump and direct discharge nozzle throw- 
ing a strong stream, preferably one-eighth 
inch in diameter. After from three to five 
minutes’ pumping the emulsion should be 
perfect, and the mixture will have in- 
creased from one-third to one-half in bulk 
and assumed the consistency of cream. 
Well made emulsion will keep indefinitely 
and should be diluted only as wanted for 
use. 
For the treatment of large orchards or 
in municipal work requiring large quanti- 
ties of the emulsion it will be advisable to 
manufacture it with the aid of a steam or 
gasoline engine, as has been very success- 
fully and economically done in several in- 
stances, all the work of heating, churning, 
etc., being accomplished by this means. 
The use of whale-oil soap, especially if 
the emulsion is to be kept for any length 
of time, is strongly recommended, not only 
because the soap possesses considerable in- 
secticide value itself, but because the emul- 
sion made with it is more permanent, does 
not lose its creamy consistency, and is al- 
ways' easily diluted, whereas with most of 
In purchasing a high duty sprayer, one 
with sufficient power to spray the highest 
trees should be selected. It is a great aid 
to economical spraying to use a machine 
capable of spraying all the trees from the 
ground, and reduce as far as possible the 
labor item. If a sprayer is not powerful 
enough to throw a mist from the ground to 
the tops of the highest trees, enough men 
must accompany it to handle the ladders, 
the hose and the apparatus. 
For general spraying a horse-drawn ma- 
chine is most generally used, but under cer- 
tain conditions a power truck sprayer can 
be used and will actually lessen the cost of 
the work. In extensive operations there 
often are outlying districts or scattered in- 
festations to be sprayed, or a strictly road- 
side proposition with great mileage to 
cover, and in such cases a power truck 
sprayer can be used to advantage. 
LOCUST BORER 
the other common soaps the mixture be- 
comes cheesy after a few days and needs 
reheating to mix with water. Soft soap 
answers very well, and one quart of it may 
be taken in lieu of the hard soaps. 
In limestone regions, or where the wa- 
ter is very hard, some of the soap will 
combine with the lime or magnesia in the 
water, and more or less of the oil will be 
freed, especially when the emulsion is di- 
luted. Before use, such water should be 
broken with lye, or rain water employed. 
For use on locust trees dilute one gallon 
of emulsion with two gallons of soft water. 
Pure kerosene and pure petroleum will 
effectually kill the insects, but may do 
some damage to the bark of the trees. 
Experiments with carbolic emulsion in- 
dicate that this preparation is of no value 
to kill the young grubs. 
According to Dr. Howard, Chief of the 
Bureau of Entomology, the brown and ap- 
parently dying condition of the yellow or 
black locust trees in the states of Vir- 
ginia, Maryland, Pennsylvania, West Vir- 
ginia and Ohio is caused by the insect 
known as the locust leaf-beetle. Nearly 
every summer the brownish appearance of 
these trees attracts attention and causes 
considerable inquiry and some alarm. 
However, with a few exceptions, the trees 
recover and come out fresh and green the 
following spring. 
A more complete description of the 
licust borer and methods for its control 
may be obtained from Circular No. 83 of 
the Bureau of Entomology, which is writ- 
ten by A. D. Hopkins, in charge of Forest 
Insect Investigations. The bulletin con- 
tains photographs of the borer. 
