A.P. Biology : Insect Collecting Methods

Collection Nets and Beating Sheets

There are three basic types of collection nets: aquatic, aerial and sweeping. Aquatic nets, used for collecting insects in water, are generally composed of a metal screen attached to a canvas bag. Aerial nets, used for gathering flying insects, are composed of a lightweight bag and handle while the sweeping net is a stronger and heavier net with a more durable bag that can sustain being swept through heavy vegetation.
An effective method for collecting insects that rest on trees, bushes and other plants are beating sheets. A beating sheet is a swatch of heavy cloth stretched across two diagonal pieces of wood which is placed beneath vegetation as you "beat it" with a heavy stick to catch the fallen insects. This method works especially well during cold weather or when insects are seeking shelter early in the day or near evening time, when they are hard to detect.
Traps and Aspirators
Traps may be needed for certain types of insect collection and there are many types to choose from including barrier traps, bait traps, pitfall traps, pan traps, Lindgren or Berlese funnel traps and blacklight traps.
If you are interested in designing your own aspirator there are simple, valved bulb plans using pressure or suction available, but there are others with a squeeze bulb that may be purchased if you are under a time constraint. There are also a number of collection traps that may be designed with a large-scale suction feature for heavier needs or captures.

Sifters, Separators and Extractors

Ground insects and mites are usually collected by sifters, which are used to forage through moss, fungi, ground litter, rotting wood and nests; they are excellent tools to use during the winter months to collect hibernating species. Easy to construct, sifters are made from simple containers with a wire-mesh screen bottom.
Extractors, sometimes called separators, are similar to sifters in that they are used to collect the creatures hidden among materials and debris, some of it unpleasant, in which the insects are concealed, such as dung, leaf mold or vegetable matter. Included in these devices is usually a drying aid or heating mechanism that helps impel the insect from the foreign matter.
Read more: Insect Collection Methods | eHow.com http://www.ehow.com/way_5402075_insect-collection-methods.html#ixzz1v99XQKLV

Here is an on-line dichotymous key for insect identification.