We Need Your Help Scouting for Asian Long Horned Beetle

Indiana residents are being urged to spend a few minutes checking trees in their yards and neighborhoods for signs of the Asian longhorned beetle (ALB), an invasive and potentially highly destructive pest.

Purdue University entomologist Clifford Sadof said early detection is the best way to contain the pest and minimize the risk to healthy trees.  "For ALB, the only tool we have is to eradicate the hosts," Sadof said. "No one wants to see apparently healthy trees cut down but the reality is that once the ALB is there, those trees are already dead."

Trees at risk of Asian longhorned beetle infestation include maple, birch, elm, willow, ash and poplar.  Identifying ALB early means fewer trees would have to be removed, he said.

"The sooner we find it, the smaller the area that could be affected," Sadof said. "The best way to protect our trees is by looking at them and reporting any suspicious signs. It takes just a few minutes to look around and it could save a lot of trees."

The Asian longhorned beetle originated in Asia and has no natural enemies in the Midwest. Infestations have been reported in Chicago and Cincinnati, putting Indiana squarely in the at-risk zone, Sadof said. He cautioned that the potential damage caused by Asian longhorned beetles is even greater than the risk posed by the emerald ash borer.

"That's because the Asian longhorned beetle can affect a greater variety and greater number of trees," Sadof said.

The Asian longhorned beetle is easy to recognize, Sadof said. Distinctive markings include:
* A shiny black body about 1-1 1/2 inches long with white spots.
* Long antennae with black and white bands.
* Six legs with bluish feet.

Signs of Asian longhorned beetle infestation are:
* Round exit holes, the size of a dime or smaller, in tree trunks and branches.
* Round or oval scars in the bark.
* Sawdust-like material on the ground near the tree or in branches.
* Dead branches or limbs falling from an otherwise healthy looking tree.

Residents who detect any of these signs should contact the Indiana Department of Natural Resources toll-free hotline, 1-866-663-9684 (1-886-NO EXOTIC). They can also download the Purdue Tree Doctor app for their mobile devices.

"The app provides photos that homeowners and professionals can use to identify both the Asian longhorned beetle and emerald ash borer," Sadof said.

Writer: Darrin Pack
Source: Clifford Sadof

Agricultural Communications: Keith Robinson 

Shade Trees and Scale Insects in Hamilton County Landscapes

High populations of scale insects are drawing attention in Hamilton County yards this spring. The insects, commonly called lecanium scales, feed on the sap of a variety of trees including maple, oak and many others. This week alone we have had two samples come into our Educational Center for problem diagnosis. One sample was found on oak while the other was a mature maple.

The first signs of scale infestation are often noticed before one sees the insect itself. Most noticeable is the sticky, wet substance on under-story plants, yard furniture, or automobiles. This material, known as honeydew, is excess fluid that is excreted as the insects feed. Under-story leaves and other surfaces may be lightly speckled or heavily coated with the shiny drops of honeydew. Eventually a sooty mold fungus grows on this substrate, blackening the foliage, twigs, and bark, and other objects beneath scale-infested trees. Dieback of twigs and branches and premature leaf drop may result as heavily-infested trees compete with scale insects for necessary moisture.

Lecanium scales can vary in size and color but are generally oval in shape. Females molt several times before reaching adulthood. With each molt, the female’s body grows bigger, while her legs and antennae become proportionately smaller. By the time of the second molt, the female scale, with her hardened, brownish, hemispherical body, is incapable of moving from the spot on which she has become fixed. Male scales are delicate, flat and nearly transparent.

Normally, scale populations are kept in check by environmental factors and natural enemies such as ladybird beetles. Heavily-infested trees may show some dieback of twigs and branches and there may be some early leaf drop. Landowners can reduce other stress on trees to help them recover. For landscape trees be sure to water in times of drought and avoid disturbances such pruning and root damage. When populations are heavy on specimen trees, horticultural oils and other insecticides can be applied.  For more information, click here for a great publication from Michigan State University Extension.

Excerpts were taken from Vermont Dept. of Forestry Lecanium scale fact-sheet.

How to Make Cicadas Shut Up

Check out this entertaining article about those noisy cicadas in Indiana.  I would be surprised if you have not heard them making the shrill mating and congregation calls of the adults the past few months. Two groups of cicadas, (periodical and annual) occur in Indiana and they are primarily nuisance pests, but some real cicada damage occurs as a result of these insects killing small tree branches and twigs when they lay their eggs.

Click here to read the full article by Timothy J. Gibb, Extension Entomology, Purdue University.