MISSOURI BOTANICAL GARDEN BULLETIN 85 
This should be applied at the rate of one-third of a pound 
to the square yard. No immediate effect will be noticed 
from the application, but, later, increased sturdiness and 
consequent richness of foliage and blossom should result. 
Insects.—Half starved and otherwise neglected roses are 
uite susceptible to insect attacks, which, however, is not 
the case if the plants are properly cared for. In St. Louis 
and vicinity the most serious insect enemy of the rose is 
probably the green fly, well known to all who have grown 
roses. It is a small, green plant-louse, or aphid, about one- 
eighth of an inch in length when full-grown and usually 
wingless. The body is oval and soft and secretes a sweet 
fluid of which ants are particularly fond. The presence of 
ants on rose bushes is good evidence that the aphids are at 
work. The latter usually work on the young shoots, suck- 
ing the juices with their long, slender beaks, and if un- 
molested quickly destroy the vigor and vitality of the rose 
plant. The most effective agent with which to combat the 
aphid is tobacco smoke, but its use out of doors is obviously 
connected with serious difficulties. In its place, however, 
a solution made from tobacco stems and whale-oil soap will 
_be found effective. To make this solution one pound of 
‘ tobacco stems should be soaked in a gallon of water over 
night, after which one ounce of whale-oil soap, which has 
first been dissolved in a small quantity of hot water, should 
\ be added (it will require three or four hours for the soap 
to thoroughly dissolve). The solution so prepared should 
be thoroughly stirred before using and may be applied either 
with a sprayer or with a whisk broom. This quantity is 
sufficient for about twenty-five plants. Where a sufficient 
water pressure is available the green fly may further be kept 
in check by vigorously spraying the plants from time to time, 
as required. 
Another troublesome pest of out-door roses is the rose 
hopper, or thrips. This insect is small, yellowish white, 
about three-twentieths of an inch long, and provided with 
a pair of transparent wings. It preys upon the leaves, work- 
ing especially on the under side, causing the foliage to as- 
sume a dekly yellowish appearance. e control of this 
insect is more difficult because of its active jumping and 
flying habits. Spraying the plants with water, so as to wet 
the under side of the leaves, and subsequently dusting them 
with powdered hellebore usually effects a sufficient control. 
Several kinds of caterpillars prey upon the rose, some- 
times causing considerable injury. All of them envelop 
themselves in the leaves or burrow in the flower buds. 
Powdered hellebore sprinkled over the plants prevents to a 
