effective. Spray with 1% DDT has proven most effective. As a dust, a 3% Ryanex 
dust has shown up slightly better than a 3% DDT dust. However, the spray seems 
considerably better than dust. 
CUT WORMS hide under clods or in the soil during the day and emerge at night to 
cut off young plants, usually at soil level. If these pests are not too numerous they 
may be controlled by carefully searching the top inch or two of soil within a few 
inches of the plant and destroying the grub which is often two inches long and 
fleshy. Heavy infestations may be controlled by scattering poison bran mash 
lightly over the garden area. 
GRASSHOPPERS need no description. Infestations may be greatly lessened by spraying 
grass and weeds surrounding the garden with a 3°% DDT spray. The wider the 
area covered with spray the more effective the control will be. 
JAPANESE BEETLES which are very destructive of blooms, and their presence readily 
detected, can be controlled by 1% DDT sprays. 
LEAF EATING INSECTS AND CATERPILLARS, whose presence is evident by their 
eating of foliage, readily controlled by spraying or dusting with stomach poisons 
such as arsenicals. DDT also seems to control, either as a spray or dust. 
LEAF HOPPERS are small greenish-yellow, flying insects which are very active in warm 
weather. Disturbing the plant will cause them to fly rapidly away and they can 
best be detected in this way. They are usually found on the under sides of the 
leaves sucking the plant juices, causing the edges of the leaves to turn yellow, 
eventually browning and destroying entire leaves at the bottom of the plants. 
Previous controls have not been very effective unless applied every two or three 
days. DDT spray at .5% (one half per cent) concentration will control them almost 
100%. DDT dusts are nearly as effective when a two or three per cent dust is 
used. Sabadilla Dust has also shown itself more effective than former controls. 
RED SPIDER MITE, or simply red spider, are very small black and white to brownish, 
minute insects, nearly always found on under sides of the leaves. A magnifying 
glass is necessary to see these tiny insects but their damage is apparent by 
browning of the lower, and to a lesser degree, the upper surfaces of foliage. 
Under sides of the leaves usually appear to have ‘'rusty'’ areas and a sort of 
silky appearance. In the past they have not been serious pests of the dahlia except 
in isolated cases. However, if DDT is used as a control for other insects, it is likely 
that red spider mite will be very prevelant and cause much damage if not 
promptly controlled. DDT has no effect on them, and, to make matters worse, 
it kills the predators or parasites which normally feed on the mites. "Dowspray-17"' 
applied according to manufacturer's directions has proven highly effective as 
a control, especially when combined with DDT. Dowspray-17, as the name ap- 
plies, is a spray material manufactured by the Dow Chemical Co., Midland, Mich. 
It seems far superior to all other standard red spider sprays. 'DN-269" another 
DN compound has proven of some value as a dust and much more effective than 
any previous dust for this purpose. Applications of spray or dust must be 
thorough and applied to the under sides of the foliage as well as the upper surfaces. 
TARNISH PLANT BEETLES are small plant bugs about a quarter of an inch long, 
brown mottled with shades of red and yellow. They are seldom seen on the plants 
as they fly away at the slighest disturbance. The bugs puncture the stalk, stems 
and buds, causing small black spots. Growth of stung part is severely checked, 
causing a shortening between nodes of the plant, shortening of stems, and causing 
buds to open one-sided or to fail to open at all. Badly infested plants are short, 
very bushy and never produce presentable blooms. A 1% DDT spray has proven 
highly effective in the control of this troublesome pest which has been very 
difficult to control before. DDT dust has also given good control as has Sabadilla 
dust, applied according to manufacturer's directions. 
40 
