December, 1916 
WISCONSIN HORTICULTURE 
53 
MADISON DECEMBER 12-14 
Plants and Ornamental Shrubbery 
Lake Geneva, August 22, 1916. 
difficult to secure packages of it 
which have not been lying 
around the shelves of the drug- 
store for considerable periods of 
time. 
Plant lice, on the other hand, 
and scale insects are rather se- 
vere on ornamental shrubs. You 
are all familiar with the effect of 
aphids on snowball, curling the 
tips of the leaves and badly dis- 
figuring the plant. They also 
disfigure several other ornament- 
al shrubs and are common on 
almost all of them, though on 
Spiraea and most of our shrubs 
they do not injure the appear- 
ance as they do on the Vibur- 
nums. 
In the case of Spirea and in all 
cases where aphids appear on 
the stem of the plants and on 
the surface of the leaves without 
curling them, you can use the 
sprays which I have mentioned 
(kerosene or Black Leaf “40”) 
in their ordinary dilutions with- 
out any difficulty. Where the 
leaves are curled, however, it is 
necessary to either dip the tip of 
the plant or else to spray before 
the leaves begin to curl. The 
actual and practical result of 
this is the fact that the snowball 
( is not being planted as much as it 
has been in the past and such 
seems to be a desirable change. 
Those who grow ornamental 
shrubs on small city lots seldom 
wish to take the trouble of spray- 
ing in order to keep the insects 
off. 
Among the flowers, asters seem 
to be most commonly attacked 
by root lice. Where it is prac- 
ticable, the most satisfactory 
method of controlling root aphids 
on a plant which is not already 
too weakened to live is to dig 
out the soil around the plant and 
put in tobacco dust. This may 
be secured from most seed con- 
cerns and a great many drug- 
stores. Pouring nicotine in liquid 
form around the base of the 
plant will kill the lice that are 
there at the time but it will not 
remain in the soil the way to- 
bacco dust will. The latter will 
allow the rain to wash the nico- 
tine out and keep washing it 
down on the roots. 
In addition to plant lice, we 
have scale insects to combat on 
ornamental shrubbery. A“scale” 
consists not only of the insect 
but of a waxy covering which 
the insect secretes. You are 
probably familiar with oyster 
shell and scurfy scales on our 
common shrubs. Lilacs per- 
haps are especially likely to have 
oyster shell, and dogwood very 
commonly has a white scurfy 
scale. These are not particularly 
injurious but if they become too 
numerous they may be con- 
trolled by a concentrated solu- 
tion of lime-sulfur in the dor- 
mant season such as is used in 
the control of scale insects and 
of plant diseases in orchards. 
One scale which has received 
a great deal of advertising the 
past thirty years is the so-called 
San Jose scale. For those who 
are not familiar with it and mis- 
take it for more conspicuous in- 
sects, I might say that this is 
the smallest scale insect which is 
common or of economic import- 
ance. The insect, itself, is much 
smaller than the head of a pin 
and the scale is just about that 
size. In the winter stage it is 
black and these scales pile up on 
the bark until they are very 
numerous. The dead ones peel- 
ing off often give the bark an 
ashy appearance. 
San Jose scale has not yet 
been found at Lake Geneva al- 
though it may be discovered 
here at any time. The most 
serious infestation in the history 
of the state is at Kenosha where 
Not all Illinois apples are good apples. There are discards from one orchard. Photogra- 
phed somewhere in Illinois Oct. 1916. 
