80 
PARK AND CEMETERY. 
Brown Tail Moth. — Spray early as the 
leaves unfold with 8 lbs. arsenate to 100 
gallons water. The best and cheapest 
method is to cut off the winter webs when' 
the snow is on the ground and the man 
below can see them easily and pick them 
up. In low plantations badly infested by 
heavy flights of the moths in summer it 
is possible to control very cheaply by 
spraying the upper sides of the leaves on 
which the young larvae feed before form- 
ing the winter web. 
Tussock Moth. — Spray early with 6 to 8 
lbs. arsenate to 100 gallons water. Creo- 
sote the egg masses any time during the 
winter. 
Elm Leaf Beetle. — Spray in summer 6 to 
8 lbs. to 100 gallons, as soon as the eggs 
are laid on the under side of the leaves. 
This work must be thoroughly done and 
the spray made to adhere to the under 
side of the leaves. The larvae feed only 
on the under surface of the leaves. They 
are not hard to kill, but it is hard to get 
the poison to stick in the right place. In 
bad localities it may be necessary to spray 
also early in the spring, as soon as the 
leaves are full size, in order to kill the 
adult beetles which have hibernated during 
the winter and which feed a long time 
before laying eggs. The adult beetles 
eat holes in the leaves, and this spray may 
be applied to the outside of the tree on 
either the upper or lower surface of the 
leaves. 
Codlin Moth .—Spray with arsenate, 6 
lbs. to 100 gallons, just as the blossoms 
fall. This spray is timed to get the poison 
into the still open calyx. This is the point 
where the little worm eats into the young 
apple. A few days later the calyx cup 
closes and it will be practically useless to 
spray for codlin moth. 
San Jose Scale— Spray with any good 
dormant contact spray early, before the 
buds begin to swell. Lime sulphur is the 
cheapest commercial spray, but in our work 
at the Arboretum it is necessary to use 
soluble oil because the lime sulphur turns 
our painted labels black. It is possible to 
kill the young, newly hatched scales dur- 
ing the summer by weak contact sprays, 
such as soap solution. There are four 
or five broods during one season and usu- 
ally there are too many other things to 
fight at this time, so that the most com- 
mon practice is a strong dormant spray 
early in spring before the buds swell. Let 
me caution you to be careful of peaches 
and all members of the almond group 
when soluble oil is the spray. It is liable 
to injure. 
Oyster Shell Scale and Scurf hy Scale 
seem to be controlled somewhat by the 
same dormant spray used for San Jose 
scale, but the surest and most common 
method now is to spray with weak contact 
spray as soap solution, 1 lb. to 10 gallons 
water, just as the young are hatching in 
the spring. The oyster shell passes the 
winter as a mass of white eggs under the 
old scale. The scurphy scale winters in 
the same way, but the eggs are red in color. 
Aphis or Plant Lice. — This is a fruitful 
field for discussion. The last few seasons 
have been particularly troublesome for 
aphis. The standard remedy is weak soap 
solution, kerosene emulsion or some forth 
of tobacco extract. To any of the above 
mixtures add a liberal amount of everlast- 
inqly-at-itness and Johnny-on-the-spot- 
ness. The green aphis is easier to kill 
than the black aphis. Some aphis pass 
the winter as black eggs exposed on the 
twigs and about the buds and sometimes 
around the base of the plant. Whenever 
the eggs are exposed soluble oil will 
shrivel them up, at the same dormant 
strength as for San Jose scale. As a gen- 
eral practice I would advise spraying thor- 
oughly top and bottom with dormant con- 
tact spray any plants specially liable to 
attack from aphis. Such a spray has 
seemed to be helpful in the case of our 
climbing loniceras as L. dioica, L. Sulli- 
vanti. L. Heckrotti , etc., which are always 
greatly troubled by aphis. The foliage of 
these plants is very tender and the struc- 
ture of the unfolding bud is such that once 
the aphis get in the terminal bud they are 
so protected that it is next to impossible 
to rid the plant of them by means of 
sprays. Constant watchfulness is abso- 
lutely necessary. 
Red Spider. — This has also been very 
bad for the last few seasons. They are 
easily reached and a weak soap solution is 
the best remedy. 
Lace Bugs or Turgitids. — These are 
sometimes very troublesome on kalmia and 
rhododendron, but are very easy to kill 
if you are only careful to hit them. They 
are always on the lower surface of the 
leaves, and so a bent-arm nozzle must be 
used. On large plantations or in com- 
mercial operations it will pay to use a soft 
naphtha soap soluble in cold water. The 
usual strength is one pint to eight gallons 
water. 
Elm Bark Beetle. — There are two insects 
which are very serious pests in this part 
of the country, but neither of which can 
be reached by any known method of spray. 
These insects are the elm bark beetle and 
the leopard moth. They are both boring 
insects. In the case of the elm bark beetle 
prevention is worth a pound of cure. The 
beetles always attack weak or dying trees 
or places on healthy limbs which have been 
injured or checked in some way. The only 
recommendation is co-operation with your 
neighbors and a continuous policy of care- 
ful pruning and watchful practice to keep 
the trees in good, vigorous condition. All 
dying trees should be cut out and burned 
during the winter. They will be full of 
the beetle and if allowed to remain will 
only spread the trouble more. 
The Leopard Moth is a very serious 
borer also, but there is at least one stage 
when we can fight it to advantage. The 
young larvae always bore first in the young 
twigs of the season. When the twig wilts 
the larvae leaves it for older and larger 
wood and will continue such borings for 
two or even three seasons. The way to 
get it is with the pole shears before the 
borer leaves the young, wilting twig. Since 
the eggs are laid intermittently from the 
last of May until the first of September, 
the only sure remedy is a careful patrol 
the last of June, the last of July, the last 
of August and the last of September. 
Older larvae may be' discovered in their 
burrows and sometimes may be dug out 
with a wire or cut out with the knife, or, 
lastly, fumigated with carbon bisulphide. 
There are no other known remedies. 
I must not close this discussion without 
mentioning one more problem which is still 
unsolved. This is the control of the saw- 
fly leaf miner on crataegus. In appear- 
ance and habit this miner is very closely 
allied to the sawfly leaf miner, so destruct- 
ive to the foliage of Scotch elm and Eu- 
ropean alder. They are very abundant on 
crataegus in the Arboretum and through 
the Boston parks. 
The larvae pass all but about six weeks 
of the year in the ground just below the 
sod. Early in May they pupate and emerge 
as winged sawflies. The eggs are laid on 
the under side of the leaf and the young 
larvae immediately enter the leaf and 
feed between the upper and lower epi- 
dermis until the last of June. Herrick, of 
Cornell, has controlled the miners in 
Scotch elm by “Black Leaf 40,” 1 to 800 
parts water, and I have duplicated his ex- 
periments perfectly. Chapman, of Boston, 
lias had similar success on elm with “Nico- 
fume” at the same strength — 1 to 800. But 
on crataegus the epidermis of the leaf is 
so heavily cutinized that even eight times 
this strength will not enter and kill the 
miner. It will injure the leaf without af- 
fecting the miners at all. I have also tried 
kerosene emulsion, 1 to 10, and also soap 
solution and nicofume in several strengths, 
but to date nothing has offered any prac- 
tical solution of the difficulty. My only 
hope lies in a report of one isolated case 
where trees badly troubled one year were 
sprayed with arsenate of lead early, and 
again later when the leaves were fully 
expanded. They were practically free of 
the miner that year. This experience sug- 
gests Slingerland’s discovery regarding the 
codlin moth, which made spraying into the 
calyx cup as the blossoms fall the standard 
remedy for this orchard pest. I shall fol- 
low up this suggestion the coming season 
and it may be that this simple arsenate 
spray applied to the under side of the 
leaves before the eggs are laid will prove 
to be the cure for leaf miner on crataegus. 
