Tom Turpin
Professor of
Purdue University







Butterflies And Nets - Oh my!

Insect collecting is a common summertime activity for many people. Insects can be collected in a number of ways, but the most common collecting method is to use a net. Technically known as a capture net, this device, along with the pith helmet and knee-length shorts, is commonly used by cartoonists to create an image of the entomologist on a collecting trip.

Insect nets can be purchased from many nature stores or biological supply houses. There are several types of collecting nets — with the most common known as the aerial net, or the so-called butterfly net — to be used to capture flying insects. An aerial net consists of a net bag attached to a metal ring, which is fastened to a handle.

In general, a good insect net should be fastened to a ring about 14 inches in diameter. The net itself should be made from a fine mesh cloth and taper to a point away from the ring. The net should be twice as long as it is wide. This length makes it possible to flip the tapered end of the net over the metal ring, thus capturing insects in the net. By grasping the narrow end of the net, the insects can be removed or released by the insect collector.

It is a good idea to reinforce the net where it is fastened to the metal ring by sewing a double portion of muslin around the edge. This also produces a channel through which the ring can be threaded.

Handles for insect nets are generally constructed of dowel rods or, in some instances, metal tubing. In commercial nets, the handle can be removed from the net to make it easier to carry between collecting escapades. Normally, the metal hoop is cut with the ends bent to fit along the dowel. The net is held in place by a short piece of metal tubing that slides over the rods.

In general, aerial nets should not be used in vegetation because they are easily torn. Nets to be used in vegetation should be constructed of light canvas or heavy muslin. They can be used in a process known as "sweeping" vegetation. In sweeping, the net is moved back and forth in a sweeping motion over the top of vegetation. This action gleans the insects resting in the plants. Such collecting also removes some plant leaves and stems, however the insects will crawl from the leafy green material.

Collecting insects with a capture net can be challenging and fun. Such activity is especially challenging if flying insects such as butterflies are the target. The first impulse of most people is to run after the flying butterfly with shouts of joy and the net held high and waving in the breeze. This is the stuff cartoons are made of, but it is not very effective in capturing the elusive insects. A much more effective method is to allow the insect to land on a flower or leaf, then use the net to make the capture. Sometimes it just makes sense to take your time, and this is especially true in insect collecting.


Writer: Tom Turpin
Editor: Andrea McCann