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Insects and Their Control 
APHIDS, OR PLANT LICE 
All aphids are true sucking insects that insert their beaks through the surface of the leaf or stem and 
extract the juices from within. 
INJURY. The feeding of aphids causes the plants to become sickly and stunted. The leaves curl 
inward, and when the flower terminal is infested the blooms will be deformed. Certain varieties 
of chrysanthemums are more susceptible to attack than others. 
CONTROL. Nicofume Fumigation is an easy method of controlling the black aphid but will do very 
little to control the green or straw colored aphids. Benzene Hexachloride or Parathion is much 
more effective on the very resistant green or straw colored aphids. Vapotone is also effective 
when used at higher concentrations. 
CHRYSANTHEMUM LEAF MINER 
The larva or maggot disfigures and weakens chrysanthemum plants by mining in the leaves. It may 
do considerable harm to the crop, but is easily held in check. 
INJURY. The young maggots burrow in the leaf tissue, leaving the upper and lower surfaces intact. 
The tunnels are irregular and winding. White blotches are thus formed, which later turn brown, 
and the leaves may die. 
CONTROL. As soon as it is noticed that any leaves are infested, they should be picked off. 
Parathion or TEPP aerosol bombs are very effective. 
CHRYSANTHEMUM MIDGE 
The chrysanthemum midge is one of the most serious pests with which the grower has to deal. Under 
optimum conditions a little over a month is required to complete the life cycle from the egg to the 
adult. The eggs are reddish-orange in color and are usually deposited on the tender tips of the growth. 
Under favorable conditions the eggs hatch in about three days. The larva wanders about over the 
surface of the leaf for a day or two before finally penetrating into the leaf. 
INJURY. The midge attacks all parts of the plant but prefers the tender growth. .If the infestation 
takes place when the plants are small, they fail to grow, although if the plants are well developed 
when the infestation starts, the buds blight or are deformed and the plant is rendered unsalable. 
CONTROL. Clean stock should be used wherever possible. Severely infested plants should be pulled 
up and burned. Nightly fumigation with Calcium cyanide or Nicofume pressure fumigators for 28 
consecutive days will give good control. Nicotine Dust is also useful in keeping the plants covered 
and is especially useful when used in combination with fumigation. Sodium selenate is effective 
when applied in liquid form '/4 gram per square foot after plants are well established. Parathion 
or DDT either as dust or spray is very effective. 
Midge Injury to Leaves and Buds 
