Wednesday, June 30, 2010

Drywood termites

Uninvited guests are always a challenge here in the Sunshine State- whether it’s insects or your aunt that won’t leave your guest room. Here’s a little bit of information about one of these unwelcome visitors, the drywood termite.

The drywood termite (genus Cryptotermes) refers to a group of termites that live within and feed on wood, as opposed to subterranean termites which have their colonies in the ground. One drywood termite in particular, the West Indian Drywood Termite, Cryptotermes brevis (pictured above), is widespread in the tropics and common in Florida. Drywood termites can be identified by looking at the wings of the alates. Alates are the reproductive stage, also known as swarmers. They have two pair of hairless wings with three or four dark veins on the leading edge of each wing. (Subterranean termites will have only two of these darkened veins.) The bodies are medium brown in color and just under a half-inch long, including wings. The alates fly from dusk until dawn and are attracted to lights. This behavior is usually noted between April and June, but we have been getting calls and specimens here at Extension with more frequency lately.

To check for damage within your home you will want to look for the following:
-A blistered appearance on wood.
-A hollow sound when wood is tapped.
-The presence of fecal pellets, or frass (pictured below, enlarged to show detail) found in piles. This frass is actually similar in size to coffee grounds, about 1-2mm.

If you suspect a drywood termite infestation, call a licensed Pest Control Operator for inspection. You may also begin by bringing a specimen to the Pinellas County Extension for identification and control information.

Drywood Termite Fact Sheet

Is it an ant or a termite?

Drywood termite control options

Thursday, June 24, 2010

Was Christo here?

Senior Extension Specialist, Andy Wilson

If the trunks of some of the trees in your yard look as if the artist Christo had wrapped them in Christmas angel hair you can probably thank psocids or webbing barklice. Psocids (Archipsocus nomas) are small, harmless insects that feed on lichens that live on the trunks of trees. They produce a tight, silk-like webbing to protect themselves from the elements while they feed. Although the webbing can look quite eerie, psocids do no harm whatsoever to the tree they’re on and no control is needed. Eventually the webbing will weather away.

Those seeing the webbing produced by psocids for the first time may fear that that it’s being caused by caterpillars that will feed on the tree’s leaves. Just remember that the webs of psocids will be against the bark and will not normally cover any leaves while fall webworm, a common leaf-feeding caterpillar on pecan, sweetgum and several other kinds of trees produces webs that encase groups of leaves.

Click here for psocid fact sheet.

Wednesday, June 16, 2010

Snowbush Spanworms

Snowbush Spanworm (Melanchroia chephise)

If you have a snowbush (Breynia nivosa) in your yard you may want to look for these colorful creatures. The snowbush spanworm (a caterpillar), is a member of the “inchworm” family. The caterpillar (larva), also known as the snowbush spanworm, emerges from eggs laid on the leaves of the snowbush. They also love to eat the leaves of the snowbush, and can be voracious eaters. These caterpillars eventually pupate in the ground and emerge as the white-tipped black moth. This beautiful moth (adult) in turn lays eggs on the snowbush plant, thus continuing the cycle. One very interesting characteristic of this moth is that it flies during the day, while most moths fly at night.

White-tipped Black Moth (Melanchroia chephise)

Now, before you break out the pesticide, consider simply enjoying the multicolored moths and caterpillars along with your colorful snowbush foliage. That being said, if you have an unusually high number of caterpillars and no predators to control them, they may damage or even destroy the plant, so you have to decide for yourself if any action is necessary. If you need to control the population you have a few options:

-Find the salmon-pink colored eggs and smash them.
-Prune branch tips with many caterpillars and dispose of them.
-Spray small caterpillars with an insecticidal soap.
-Treat with Bacillus thuringiensis (B.t.) product such as Thuricide or Dipel. This is a biological control (a bacteria in this case) that is only toxic to a specific group of insects.

Please see the following fact sheet written by Doug Caldwell, an extension agent and entomologist in Collier County. This fact sheet contains more photos, including that of the eggs: