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Whiteflie s are among the commonest insects found on ornamentals in 
the house, greenhouse, or window box. These small insects get their name 
from their appearance; their wings are snowy white, whereas their bodies 
may be yellowish or pinkish. When the plants are disturbed, the adults take 
flight and are easily recognized while flying over and around the foliage. 
The younger forms of the whitefly are wingless and pale green, and they 
attach themselves to the under surfaces of the plant. Both the adults and 
the young feed, as do the mealybugs and scales, by sucking the plant juices. 
Infested plants lack vigor, and, when severely infested, may wilt, turn yel- 
low, and die. The plants most commonly affected include geranium, fuchsia, 
ageratum, lantana, coleus, begonia, calendula, solanum, and many others. 
Aphids, or plant lice, are also common pests of a very wide variety of 
ornamental plants. These insects are soft-bodied, usually green, although 
some forms, such as the nasturtium aphid, are nearly black, and others are 
pink, red, or brown. They usually live in colonies or clusters on the most 
tender portions of the plant. Both winged and wingless plant lice may often 
be seen in the same cluster. Aphids feed by sucking the plant juices and, 
when abundant, cause severe curling and shriveling of the infested leaves and 
growing tips. One or more species of aphids attack nearly every species 
of ornamental plant. 
T hrips are of several kinds. They are slender-bodied insects, yellow- 
ish to brown or black, the immature forms of which are without wings, whereas 
the mature forms have wings and can fly readily. They are difficult to see, 
however, because of their small size. The thrips differ from aphids and 
scales in their manner of obtaining food in that they first rupture the plant 
tissue with their mouth parts and then suck the plant juice. Their feeding 
causes a v/hitish spotting or "silvering" of the foliage, and the edges of 
the leaves wither, curl up, and die. Small black specks, which represent 
excretion from feeding, are usually present on the leaves of plants on which 
these insects have fed. Fuchsia, croton, cineraria, ageratum, and many 
other ornamental plants are attacked by thrips. 
Red spiders (or mites) are not true insects, since they have 8 legs 
and insects have only 6. They obtain their name from the resemblance they 
bear to spiders, but are so small as to be scarcely visible to the naked eye. 
Red spiders vary in color, but are usually reddish or greenish. They do 
most of their feeding on the under surfaces of the leaves by extracting the 
plant juices, but in cases of heavy infestation they feed on both surfaces 
of the leaves and on the stems of the plant, often covering the area over 
which they roam with a light web. Fed-over leaves first have a whitish 
appearance, later turning brownish and oftentimes dying. Most plants are 
subject to the attack of red spiders, but some of the smooth, hard-leaved 
plants, such as certain palms, are only moderately injured. 
Fungus gnats are small, delicate, flylike insects. The adults are a 
nuisance in the house, as they fly to light and may be found, when present, 
swarming over the windows. The immature forms are small white maggots, and 
they live in the soil in pots of plants. They are particularly fond of soils 
containing large quantities of decaying vegetable matter. The maggots cause 
