Your Extension Experts
September 5, 1997
July 25, 1997
June 23, 1997
May 12, 1997
March 17, 1997
Volume 3: no. 5
The summer has flown by and fall is already in the air. I'm thankful to see it come for perhaps some of my `farm' activity will now slow to a less hectic pace. This has truly been the year of the insect. We have had more than usual `pest outbreaks' in many of our crops and have really struggled to manage them. Now is the most ideal time of the year to collect insects, for there are more moving about now and they are in greater numbers than at any other time of the year. I have seen more butterflies and moths than ever in my remembrance. So if you have an insect collection to make for school or one to augment before the fall fair show season, now is the time to get busy. In this issue of the `Gloworm' is a review of some of pinning, preservation and preparation for display activities with which collectors should all be familiar.
We completed our second Entomology Camp in June, successfully, with more than 40 campers.
I've enclosed some pictorial highlights of the camp in this Gloworm, it was great fun! We are already planning next year's edition for the first week in June, 1996. Put that date on your calendar and join us for a week of `bug chasing'. We plan to go south in 1996 to another of our great Mississippi State Parks.
Most collectors concentrate their efforts on adult insects and most adult insects have a hard exoskeleton which is resistant to decay if kept protected from the elements and scavengers. It is very important that collected material be `worked-up' as soon as possible after collection. This insures that the insects are still pliable and easily managed. All insect specimens will become brittle after they dry and then will be almost impossible to pin or have their appendages positioned. The pinning process should leave the insect looking as natural as possible while displaying its attributes to the best advantage. Lepidoptera should always have the wings spread when they are pinned. Beetles and other insects should have the legs and antennae positioned so that they can be observed and so that they look natural. Pinning blocks and other materials are essential to developing a quality collection. Insect pins should always be used to pin insects. (These are readily available from most Mississippi 4-H Agents. the MSU Entomology Dept. and can be ordered directly from the Young Entomologists' Society.) Once insects are pinned and dried they should be placed in air tight boxes or at least in boxes where scavengers and moisture are excluded. Moth balls or crystals should always be kept in boxes where insects are held or displayed. Display boxes may be constructed (as per specifications) or purchased through the county 4-H office.
Some species of insects are soft bodied, even as adults. Aphids, lice, springtails, silverfish, termites, and other groups are in this category. Almost all immature insects are also soft bodied. If these specimens are pinned or pointed they will shrivel and decompose, therefore they must be preserved in another way. The most common way to preserve soft bodied insects is by placing them in 70% ethyl alcohol. There is a drawback to this method, in that the specimens often lose their natural color. There are 2 ways to overcome this shortcoming. They are - 1) kill the insects in boiling water and 2) kill the insects in KAA. (KAA is a mixture of 1 part kerosene, 2 parts acetic acid, and 10 parts 70% ethyl alcohol. Acetic acid and ethyl alcohol are generally available at drug or photographic stores.) After killing the insects in boiling water they can be transferred to 70% alcohol. Insects killed in KAA should be kept there for 2-5 days then transferred to 70% alcohol vials. Smaller insects require shorter times in the KAA fixative. Soft bodied insects may also be preserved by freeze-drying. This is a difficult process which requires the use of a hazardous chemical and is not generally very satisfying. Insects may also be embedded in plastic. This process is also slow and takes practice. Plastic and catalyst may be obtained from any good craft or hobby shop. The main problem with this procedure is that air bubbles form around the embedded specimens leaving them silvery in appearance.
Specimens are most often mounted using insect pins directly through the body. When pinning insects it is important to keep pin alignment and placement in mind. The illustrations below demonstrate the `correct' and the `wrong' way to align and place the insect pins. Note: with all pin mounts the pin head is about 1/4" from the back of the insect. Some insects are so small that they must be card pointed. Pass the pin through the base of a card point and mount the insect on the tip of the card with a small amount of glue. (Make the points as small as feasible so as not to detract from the insect.) Insects as small as leafhoppers, fleas, boll weevils and others may look better on points. Insects preserved in alcohol may be displayed in vials secured in the collection box by pins. Slide mounts are not usually displayed in a collection.
Correct labeling of insect specimens is as important as catching them. Each insect should have its own personal history related on the small cards in the collection. Each collection should have Order names, common name of insect, and date, locality and collector information. The order label should be placed in the front of the first insect of that particular Order with the remainder of the insects in that Order aligned behind. The date, locality and collector label should be placed on each insect pin beneath the specimen. The common name label should then be placed on the pin beneath the date, locality, collector label.
Dr. Michael R. Williams
Entomology & Plant Pathology
Mississippi State, MS 39762-9775
phone - 601-325-2085
home - 601-323-5699
FAX - 601-325-8837