54 
WISCONSIN HORTICULTURE 
December, 1916 
TUESDAY, WEDNESDAY, 
the staff of the State Ento- 
mologist’s office has been work- 
ing for a couple of years. There 
every infested tree discovered 
was thoroughly sprayed this last 
spring and it is probable that a 
large percentage of the scale was 
entirely killed in that vicinity. 
The scale has also been found in 
Milwaukee and other cities but 
if as much is done in the com- 
ing years as has been accom- 
plished during the past year, it 
is probable that we shall greatly 
reduce the infestation of this 
very serious pest. 
The host plants include all our 
fruit trees except the cherry, 
and in addition roses, Japanese 
Quince, dogwood, sumac and 
certain other shrubs. Barberry 
and spiraea are not attacked. 
Wherever this insect is suspected 
a sample should be sent to the 
State Entomologist’s office and 
the situation will be given im- 
mediate attention. 
* * 
GREENHOUSE INSECTS 
The most common insects 
affecting greenhouse plants are 
aphids or plant lice, and white 
Hies. The latter are not true 
flies but are closely related to 
plant lice; they fly, however, 
much more freely and instead of 
being green in color are covered 
with a white mealy powder as 
the name indicates. Greenhouse 
men are all familiar with them. 
Greenhouses, as was said a few 
moments ago, however, are fumi- 
gated, especially throughout the 
summer season, at intervals of a 
week to ten days. Consequently 
florists have little trouble with 
these two groups of insects. 
They are kept under control by 
fumigation at this interval. In 
unfumigated gieenhouses white 
flies often cause, on the other 
hand, considerable injury. 
The insects which are not con- 
trolled by fumigation are cater- 
pillars and scale insects, on 
palms, rubber plants and ferns. 
For these it is desirable to use 
whale oil soap in the proportion 
of one pound to a gallon, except 
with ferns which are too tender 
to endure soap in this strength. 
Almost all palms have a few 
scale insects but they should not 
be allowed to pile up in several 
layers on these plants and on 
Ficus. We have received leaves 
of the latter plant completely 
covered by two or three layers 
of the scale insects. 
The common chewing insects 
in greenhouses are the rose leaf 
rollers and various other leaf 
rollers and leaf tiers. With one 
exception these may be easily 
controlled by lead arsenate 
sprays by using one pound of the 
powder to 50 gallons of water. 
This will not injure the rose foli- 
age as Paris green may do. One 
caterpillar against which florists 
should be on their guard is what 
is known as the Florida fern 
caterpillar. It is the only insect 
which eats the leaves of ferns and 
an epidemic in the greenhouse 
is a difficult one to handle. So 
far as I know, it has entered the 
state but once, and I believe is 
not now present in that green- 
house but should it come in, as 
it is likely to come in on ferns at 
any time, the greatest care 
should be used to prevent its 
multiplication and breeding in 
those surroundings. The nature 
of the fern is such that lead ar- 
senate colors the foliage to an 
undesirable extent and also the 
deposit of the poison on the 
foliage of a plant handled as 
much as a fern sometimes is, is 
somewhat dangerous. Hand- 
picking of the caterpillars is the 
most successful control measure 
now known. 
One cause of great trouble in 
the greenhouse is the red spider 
which will iniure almost every 
plant. Lime-sulfur spray is a 
help in combatting it. Pow- 
dered sulfur has also been found 
very satisfactory. Water under 
pressure is often used with suc- 
cess. 
This covers the principal in- 
sects injuring shrubbery and 
greenhouse plants in this state. 
There are many others of lesser 
importance but none which seem 
to require special measures for 
control. 
Orchard and Garden 
Some varieties of dahlias may 
be forced in the greenhouse with 
success. 
An inch or so of sand over the 
root crops stored in the cellar will 
keep them from drying out. 
Gladioli and dahlias may be 
stored in an ordinary potato 
cellar. Cannas require a warmer 
place. They should not be dry 
enough in any case to shrivel the 
roots. 
Rose bushes may be laid down, 
if the ground is frozen hard, and 
covered with straw and boards. 
Cover so that no moisture can 
reach the foliage. 
It is worth while to save a few 
bundles of grain to put in the 
yard for the brids during the 
winter. Birds also like suet. 
It will be well to order flower 
and vegetable seed this year as 
soon as the catalogs appear, 
since it will be hard to get the 
varieties commonly grown in 
Europe. 
