1912. 
'TJHfcO RURAb NEW-YORKER 
187 
CONTROLLING THE WOOLLY APHIS. 
I want to get hold of the simplest, easiest and quickest 
way to get at and destroy the little colonies of Woolly 
aphis that infest the crown roots and gradually extend to 
'he more remote roots of the apple. I have tried hot 
water—which was recommended—and kerosene emulsion, 
and I am inclined to think that neither one of these reme¬ 
dies is safe in the hands of an amateur orchardist, as he 
is quite likely either to get the water too hot, or not hot 
enough; and is likely to get the emulsion too strong of 
kerosene. Anyway, several of my young trees died, and I 
am more inclined to think they dieel at my hands than 
because of the aphis. An examination prior to treatment 
showed conclusively that they were affected with the aphis, 
and a post-mortem investigation revealed no aphis. There 
was the dead tree; was it myself that killed it through 
lack of knowledge as to how to use the remedies men¬ 
tioned or was it the aphis? The root systems of the great 
majority of my trees are small, owing to the fact that 
many of my trees are not more than 2Vq years old, many 
of them being not more than 1% years old. With such 
small root systems it is easy to get at them to treat them, 
and I have been wondering if some simple and safe remedy 
canuot be found to put into the hands of the amateur tree 
doctor. I am told that wood ashes are good for apple 
trees; also I have been led to believe that lime should be 
applied to the soil in sections where it is devoid of such. 
All water here is soft, and I assume there is no lime in the 
soil; if so, will it restrict the operations of the Woolly 
aphis to apply, say a pint of thoroughly air-slaked lime 
and a quart of wood ashes, or any othef quantities, in a 
little trench two or three inches away from the trunk of 
the tree, and not quite down on the roots? Would an 
application at the strength mentioned, or stronger, do the 
trees any good? What would he the effect on the trees? 
Would it damage, the aphis materially? . c. w. 
Stone Mountain, Ga. 
The Woolly aphis is one of the serious insect pests 
on apples, especially on young trees. We have seen 
all of the trees in young orchards in the South af¬ 
fected, and some of them so seriously that they were 
easily blown over by the wind. In examining these 
trees, we found the roots decayed so 
that the trees broke off clean at the 
crown, having nothing to support them. 
Even though the trees do not break over 
they will not make the growth they 
ought, for the feeding roots have been 
destroyed. There are two forms of the 
Woolly aphis, one appearing on the 
branches and one living upon the roots 
below ground. The underground form 
is much the more serious one 
On infested trees throughout the 
Summer one will find bluish-white, cot¬ 
tony masses on the trunks and branches, 
especially on the water sprouts. These 
are the colonies of Woolly aphids and 
usually, they may be taken as an indica¬ 
tion that there are other colonies on the 
roots of the trees underground. These 
root forms also live in colonies or 
groups, and secrete a similar cottony 
substance that makes them conspicuous 
when sought for. They cause abnormal 
growths or knotty excrescences to form 
on the roots. In course of time the affected rootlets 
die and decompose, and the tree succumbs; but since 
the aphids have also disappeared with the decomposi¬ 
tion of the roots the cause of death of the tree is ob¬ 
scure and often ascribed to something else. An in¬ 
fested tree appears sickly, does not grow vigorously, 
and the leaves assume a pale, yellow appearance. The 
tree becomes weakened and susceptible to the attacks 
of borers and other insects and finally dies. 
METHODS OF CONTROL.—The Woolly aphis is 
very prevalent in nurseries, and is probably often intro¬ 
duced into orchards by setting out infes.ed trees. The 
first precaution to be taken, then, is to examine care¬ 
fully the young trees as they come from the nursery. 
If infested, either reject them entirely or dip them 
in 15 per cent kerosene emulsion. The stock should 
first be carefully freed from lumps of dirt and the 
roots then dipped for 1)4 to two minutes in the emul¬ 
sion. The trees should then be spread out for a few 
minutes to dry but should not be piled in bunches, 
because the emulsion from the trees on top would 
drip on those below and this accumulation of the 
liquid might cause injury. 
Messrs. Reed and Dean, under the direction of 
Professor R. I. Smith, State Entomologist of Georgia, 
carried on during the seasons of 1906 and 1907 a 
rathgr complete series of experiments on the control 
of the root form of the Woolly aphis in Georgia. 
I ney tried tobacco dust, kainit, a combination of 
kainit and tobacco dust, common salt, tobacco de¬ 
coction, whale-oil soap, carbon bisulphide, and kero¬ 
sene emulsion. All of these substances were applied 
in varying quantities and strengths and under diverse 
conditions. As a result of these careful and extended 
trials all of the materials were discarded as unsatis¬ 
factory and ineffective against the aphis with the 
exception of kerosene emulsion. They say “without 
.going into details concerning the different tests of 
kerosene emulsion, it may be stated that all the aphis plied the earth should be replaced evenly about the 
were killed by every application, from the weakest 
to the strongest, wherever the emulsion came in con¬ 
tact with the infested roots.” 
MAKING THE EMULSION.—The following for¬ 
mula and directions for making the emulsion should 
be carefully followed: Kerosene, two gallons; 
whale-oil soap (a potash soap), one-half pound; 
water (rain or soft water), one gallon. Place the soap 
trunk of the tree. One application a year is sufficient 
and an application two years in succession, if well 
done, should free a tree of the aphis. Professor Smith 
says that the “aphis may live outside the circle treated 
with the emulsion, but as long as the odor of the 
kerosene remains in the soil the young aphis will not 
work back to the main roots of the trees.” More¬ 
over, if the aphis is kept off the roots for two or 
three feet on all sides of the trunk the tree will send 
out new roots, regain its vigorousness and overcome 
the effects of the attack. 
REPELLENT EFFECT IS LASTING.—A thing 
greatly in favor of kerosene is the lasting effect of 
its odor and repellent qualities. Mr. Reed found that 
the odor of the kerosene was plainly perceptible in 
the soil about trees on July 11 that had been treated 
3)4 months before. Their opinion of the repellent 
effect of the emulsion is summed up as follows: 
“As a repellent the kerosene emulsion acts perfectly. 
It is true that aphids may live outside the circle 
treated with the emulsion, but as long as the odor 
of the kerosene remains in the soil the young aphids 
will not work back to the main roots of the tree.” 
PRECAUTIONS TO BE OBSERVED.—It may 
be surprising to some to know that the emulsion 
should not be applied to trees while they are dor¬ 
mant. The roots of dormant trees seem to be more 
WOOLLY APHIS ON APPLE TWIG. Fig. 55. 
in the water over the fire and heat until it is dis¬ 
solved. Pour the oil into the barrel or other recep- susceptible to injury and trees have been killed by 
tacle containing the spray pump and when the water applying this emulsion while they were in a dormant 
and soap are boiling hot pour them into the barrel, condition. Probably the best time to apply the emul- 
Pump tHe mixture vigorously back into itself by re- s > on is while the tree is in full growth and the roots 
moving the cap from the nozzle and directing the are crowded with sap, say in June or the first part 
hose into the barrel. It will probably take 10 or 15 of J«ly- 
minutes of vigorous pumping to make a creamy emul- CONTROLLING THE BRANCH FORM.—The 
colonies of aphids on the branches may 
A NURSERYMAN’S BENCH—SHOWING ROOT GRAFTS. Fig. 56. 
sion. If, for any reason, the soap and oil fail to 
emulsify, the whole batch would better be thrown 
away and another attempt made. For a 15 per cent 
solution add 10)4 gallons of water. 
HOW TO APPLY THE EMULSION.—First, re¬ 
move the earth around the trunk of the infested tree 
be controlled by spraying with whale-oil 
soap. A brand of soap made with 
potash should be obtained and used at 
the rate of one pound to six gallons of 
water. The wash should be sprayed on 
with a good deal of force and in liberal 
quantities so that it will penetrate the 
cottony mass and reach all the lice. If 
the solution is applied warm it will pene¬ 
trate the mass more effectually. The 
black leaf tobacco extract at the rate 
of one gallon to 70 gallons of water with 
three pounds of whale-oil soap added 
forms a very efficient and easily made 
wash. 
NORTHERN SPY ROOT-STOCKS. 
—Varieties of apple vary in their power 
of resistance to attacks of the Woolly 
aphis, and it is an interesting fact that 
the roots of the Northern Spy apple are 
very resistant to this insect. For this 
reason it is strongly recommended that 
one should plant only those trees that 
have been grown on the root-stocks of the Northern 
Spy apple. Of course this recommendation is in¬ 
tended for those who are trying to grow apples 
where the Woolly aphis is especially troublesome. 
Cornell University. glenn w. herrick. 
... Aiv 
; tzi 
A HIRED MAN WORTH KNOWING. Fig. 57. 
to the depth of two or three inches in a circle from 
two to four feet in diameter, depending upon the 
size of the tree. Then soak the soil in this circle 
with the emulsion, using from three to five gallons per 
tree. The soil should be fairly dry in order to obtain 
the best results. When the emulsion has been ap- 
A CONCRETE BARN. 
Referring to inquiry of G. I. B., page 144, I built 
a' concrete barn on my Rockland County farm in 
1906. Walls are double, eight inches thick, each 
with six-inch air space between; height to ceiling, 
11 feet. The two walls are bound together every 
four feet with anchors, 14-inch, made out of old 
buggy tires, and the walls themselves are reinforced 
in a proper manner. Size of building is 35x70 feet, 
now used for a horse barn, but will as soon as my 
apple orchards warrant it, be turned into an apple 
storage-house. Flic loft over the stalls is equipped 
with track and hay fork and holds 50 loads of hay. 
This barn is in the Summer the coolest and in the 
Winter the cosiest place on the farm. The forms 
were made of ?4-inch tongued and grooved N. C. 
pine 14 feet long, nailing three boards together with 
cleats two feet apart. Two men were kept busy set¬ 
ting up the forms; one-third of these, or about 70 
feet, were filled each day; while the third part was 
being filled the first part was being set up again, 
making the job a continuous performance.- The 
outside braces consisted of 2)4x4 inch spruce; they 
were held in place by bale wire and this was left in 
the walls. On a later construction of a cement cop¬ 
ing for a wall in front of my house I used one-half 
inch bolts, with nuts and washers to hold the forms 
together. These bolts were smeared with heavy oil 
and were pulled out after the concrete had set with¬ 
out any trouble. They are much better than wire, 
but cost more. This wall is built out of cobble¬ 
stones pointed up with black cement, is about 200 
feet long, and is a beautiful piece of work, being 
Hanked by two massive piers on either end for gate¬ 
way posts. I could not improve much on the con¬ 
crete barn, and wish that all my farm buildings 
were of this material, as it always looks neat, does 
not decay, excludes rats and mice and is sanitary. 
Rockland. Co., N. Y< Hermann h. lucke. 
