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Often known as one of the pest of the insect world, the aphid is a very tiny insect that feeds on a variety of plant forms. This amazing insect from the Aphidae family is one of the fastest reproducing in the Homoptera order of bugs. No larger than 1/8 inch long, this minute creature has been known to produce as many as thirteen generations in a single season. Aphids, like many other insects in the Homoptera order, secrete a substance known as honeydew that is a food source for some ant species. In most instances they live in large colonies that number in the hundreds and can be found clinging to the tips of new growth on the plant source they have chosen as their habitat. The best way to observe the aphid colonies is to visit a field of weeds during the early months of summer. With over 4,000 species of this insect they can easily be observed on most budding plants throughout the world. Without a magnifying glass you may have a difficult time seeing these tiny creatures. But in most cases you will notice tiny brown spots that appear to be a form of scale on the plant. This is the skin that has been left behind by the nymph during its development. Since some aphid colonies are not larger than the tip of a sharpened pencil, with close observation you may be able to discover a tiny insect, some with wings that are clear, as it scurries about feeding and giving birth. But be aware of the very protective ants that are often found mingling with aphids, since they are quick to sting any intruder.
One of the most fascinating aspects of the aphid is the way they reproduce. During the early spring month’s wingless females hatch from eggs that have been deposited either on the food source plant or near it during the previous fall. These wingless females immediately produce live nymphs that are also wingless females. This process of reproduction, which is also known as parthenogenesis, continues throughout the spring and into the summer months. During the summer months some wingless females will produce winged females from time to time. Once the winged females have matured they will fly away to begin a new colony on another plant. The new winged females will produce wingless females to build their colonies until around the middle of the summer months. Depending on the species of aphid, from the middle of summer until around the beginning of the winter months the newly produced females begin giving birth to males as well as females. Once the males and females of the species have mated the fertile female will lay eggs that do not hatch until the following spring. This amazing form of reproduction produces millions of aphids, with the larger colonies being associated with serious damage to plants.
Since different species produce various colors in this insect the best way to recognize the presence of aphids is to be aware of the plant damage that can be found within the area of the colonies. In some cases the new leaves of the food plant will often be curled with a grayish color at the tips. New plant growth will be stunted and appear wrinkled. Aphids are known to attack many different forms of plants including some vegetables such as beans, tomatoes, cabbage and potatoes. But they can also wreck havoc on trees such as apple, pear or white pine, as well as, ornamental trees and bushes. While these are only a few of the plants effected by aphids, these tiny parasitic insects can just as easily infest houseplants as those outside the home. In agricultural areas this insect is commonly called plant lice due the tremendous amount of damage they can cause. Studies have shown that some of this damage is due to various plant viruses that have been taken plant to plant by the ever-growing colonies of aphids. Even so, aphids have a number of predators, some of which can be safely released into infested areas to reduce their numbers. Predators of this insect include the ladybug larvae, green lacewing larvae, birds, spiders, syrphid fly larvae and some species of parasitic wasp. In most instances the ants that feed from the aphids excreted honeydew will protect them from predators, even aggressively attacking in numbers.
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