Tuesday, June 3, 2008

Critters to keep an eye out for!

The Crane flies have been out for a while now. You know, the mosquito hawks, skeeter eaters or gollywhoppers as they are sometimes called. There are many different species here in California, especially the Giant Crane Fly which grows to 1 ½” long!

These bumbling, wobbly fliers blip and bang about the ceiling, walls and windows where they inevitably land in a cellar spider web. Their long, delicate legs easily break at the slightest touch. This last may be an adaptation which enables them to escape birds, their mortal enemies. So what do they do? Nothing really, except mate, lay eggs and die. Some few species may eat pollen or nectar but not enough to qualify as a pollinator.
It is the larva that concern us the most. The eggs are laid in moist environments such as turf and by streams. Eastern species may eat mosquito larvae as well as ROOTS. Our western species just eat ROOTS. The leatherjackets (the larvae are called this due to their beige, wrinkly skin), when in great numbers can damage a lawn by eating the roots, causing irregular brown patches to form.

It's easy enough to check/sample for them. Using a bread knife, cut the lawn at the edge of a damaged spot about 3” down and then cut out a divot 6” long. Peeling back the sod you'll be able to observe any grubs. Pay special attention to birds on the lawn . They're good indicators of crane fly larvae and a good biological control as are predacious ground beetles. If turf areas are over-stressed (too much for the birds), beneficial nematodes are recommended. Bayer Grub Control may also be considered.


Snakeflies have been unusually prevalent this year. This beneficial is the type of insect that may startle you when it lands on your arm unexpectedly. They also have a startling bite! These insects require cool temperatures to develop. It could be that we have snakeflies in cool years and some other type of PREDATOR in warm years such as antlions and lacewings.

Very little is known about them. Serious study did not begin until the early 1960’s. In fact 70% of the 206 known species were only named in the last 40 years. They are living fossils, much like the cockroach, dating back to the Early Cretaceous Period. Both the adults and larvae eat aphids and other soft bodied pests such as small caterpillars. The voracious adults make short work of leaf rollers, codling moth larvae, rose caterpillars and quite possibly LBAM. There was an attempt a few years back to establish snakeflies in New Zealand to control codling moth but it didn’t work.

The larvae did great work devouring the “overwintering” codling moth pupae but the temperatures were to warm for them to develop into adults. Look for the adults in woody shrub borders. The larvae hide under bark or leaves. The larvae are creepy-looking too with a long, slender scorpion-like abdomen and the same long thorax and elevated head the adult has. They have very prominent jaws.

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