What are These Bugs in My Sod?

What are These Bugs in My Sod?

On a daily basis, it is not unusual for our Extension Office to get calls, emails, and walk-ins with questions about insect identification.  Sometimes we even get questions about imaginary insects!  The overwhelming opinion by our clientele is that the insects in question are harmful to their landscapes and gardens.  This is not always the case since there are more than 100,000 species of insects found in the United States, but less than 1% are harmful.

Recently I received a call about an abundance of bugs in a client’s newly installed sod.  He was concerned that the insects were taking over his yard.  Luckily, he was able to submit some good quality photos so the University of Florida/IFAS Extension Service could help him identify the insects.

Ground Beetle

An adult ground beetle (Mochtherus tetraspilotus). Photo Credit: Michael C. Thomas, Florida Department of Agriculture & Consumer Services

The photos were sent to a University of Florida Entomologist for identification verification.  It turns out the insects were ground beetles (family Carabidae).  Adult ground beetles are slender and range between 1/4″ and 3/8″ in length.  Their head and thorax are much narrower than their abdomens.  Ground beetles are beneficial insects that feed on moth eggs and larvae.  They are known predators of soybean loopers, cabbage loopers, and velvetbean caterpillars.  It is suspected that the beetles found by the client came from the sod farm and were living in the thatch layer of the sod.  They were possibly feeding on sod webworms or other moth larvae.

Accurate identification is the first step of integrated pest management (IPM).  In this case, the insect found wasn’t a pest at all.  If you need help identifying an insect, feel free to contact your local Extension Agent.  For more information on beneficial insects, visit these publications found at edis.ifas.ufl.edu.

He’s Bored, But He Didn’t Kill Your Tree

He’s Bored, But He Didn’t Kill Your Tree

Sometimes you don’t realize a tree is dying until it is dead.  A few weeks ago, we got a call from a client who said he had insects killing his trees.  Before having someone drive out to the property, our Master Gardener volunteer recommended that the client bring in some of the insects for us to take a look.  It turned out the insects invading his pine tree were a type of longhorned beetle, but more specimens were required for identification.  A site visit soon ensued.

There were a number of pine trees on the property, however only one was infested with the insects in question.  Upon closer investigation, we noticed a number of different sized holes in the tree.  The larger holes are nearly the size of a dime.

Arrowhead borer damage on a pine tree.

Arrowhead borer damage on a pine tree. Photo Credit: University of Florida/IFAS Extension.

It turns out the insects making the larger holes are a type of longhorned beetle known as an arrowhead borer (Xylotrechus sagittatus).  The borers are brown to black in color with a reddish hue.  They are moderately hairy and some specimens contain arrowhead markings pointing toward their heads.  Adults feed on the bark of damaged or fire-killed pines.  The adults are attracted to lights and may be mistaken for crickets because they run very fast.  Eggs are laid in bark and larvae feed on sapwood, then tunnel deeper, often tunneling within a single annual ring.  The borers pupate inside the tree and the newly emerged adults chew their way out.

A picture of an arrowhead borer.

Arrowhead Borer. Photo Credit: Tom Murray bugguide.net.

Given the fact that arrowhead borers are attracted to dead or dying trees, the killer of this particular tree is still in question.  The smaller holes in the bark picture above were created by a much smaller beetle, but we were unable to get a specimen.  We did see a couple of these beetles running around when we dug deeper into the bark.  The small beetles that we saw closely resembled a type of Ips engraver beetle.  Beetles in this genus have been known to kill trees, but most likely they weren’t the culprits either.  Based on the overall appearance of the tree and the fact that other trees in the area were not infested with beetles, it is believed the tree was killed by other means.  The tree was likely struck by lightening or suffered from poor genetics because it did not have a good form for a pine tree.

If you have a questionable looking tree on your property or if you have insects you would like identified, please feel free to stop by your local Extension Office and ask a Master Gardener!

Beetles to the Rescue

Air-potato-with-bulbil-inset_largeAir potato (Dioscores bulbifera) is a perennial, herbaceous self-twining vine that can grow over 60 feet in length, enabling it to climb over and smother many native plants. The Florida Exotic Plant Pest Council (FLEPPC) lists air potato as a Category 1 invasive plant, which means that it has disrupted natural communities and ecological functions by displacing native plant species.

In 2012, a leaf feeding beetle (Lilioceris cheni) was introduced into South Florida from China for biological control of air potato. Although it is too early to determine any potential long-term impacts, the initial results have been promising. The larvae and adults of the air potato leaf beetle feed on the leaf tissue and occasionally the bulbils. The damage to the growing tips of the plant have dramatically reduced its ability to cover native vegetation. Extensive damage to air potato was evident within three months after the first release. Additionally, testing by scientists at the USDA/ARS Invasive Plant Research Laboratory in Fort Lauderdale concluded that the beetle will not complete development on any other plant found in Florida.air_potato_leaf_beetle09

airpotatobeetleThe female air potato leaf beetle lays an average of 1,200 eggs, which develop into larvae in about four days. The young beetles skeletonize the air potato leaves for the next eight days and then pupate into foam-like cocoons. Clumps of cocoons fall to the ground and the adult beetles emerge 13 to 16 days later. There can be a new generation of air potato leaf beetle every month while the weather is warm. For the winter, the adults hide in leaf litter and wait for spring.

 

The question now is: “How well will they survive through a longer, colder Northwest Florida winter?”. USDA scientists, UF Extension agents and citizen scientists in Bay and Okaloosa County hope to find out. Earlier this month, June 2015, air potato leaf beetles from the Hayslip Biological Control and Research and Containment Laboratory in Ft. Pierce were released into areas containing air potato. They will be monitored over the next year. Look for an update next summer.