ACORN NEWSLETTER July 2002

Table of Contents   ACORN News   Links   Featured Natural Enemy: Spined soldier beetle and stink bug   Featured Alternative Control: Neem Bioinsecticide

ACORN News   ØWe have approximately 80 gardeners conducting 6 different experiments. Thanks for being such great volunteers!   ØIn September, we will be sending you another survey to determine how you managed your pests this year.   ØI will be out for a couple weeks at the end of the summer. Don't hesitate to contact me via email at <fheraux@entm.purdue.edu> or telephone at (765) 494-1422. Kim Rebek, a graduate student who worked with this project during the summer of 2000 will be the contact person during that time. If you have any questions concerning the datasheets or entering the data on the website, please don't hesitate to contact her.     Some Useful Links   New website at Purdue University! Purdue University Extension Garden Tips http://www.ces.purdue.edu/gardentips/ Newly updated E-47W "Periodical Cicada in Indiana". Find out when they will be active in your area. http://www.entm.purdue.edu/entomology/ext/targets/e-series/EseriesPDF/E-47.pdf If you have a website that you would like to share with other gardeners, please send me an email at <farah_heraux@entm.purdue.edu>.

 

Featured Natural Enemy: Spined Soldier Beetle and Stink Bug

 

Introduction: Spined soldier beetle and two-spotted stink bug are commonly referred as the stink bugs. Many stink bugs are plant feeders but these two important are predators.

 

What to look for?
Stink bugs are easily identified by their broad, shield-shaped bodies.

The adult spined soldier beetle is brownish and about ¼ inch long with a prominent spine on each shoulder. (link to ACORN with picture) In Indiana, the adults emerge around mid-April and there are 1 to 3 generations per year.
To see a picture of a spined soldier bug adult, click on the following link <<http://entm29.entm.purdue.edu/acorn/ne.aspx?ne=Spined_soldier_beetle>>.

 

Spined soldier beetle eggs are deposited in masses of 15-70, and range in color from cream-colored to black.

 

The immature of the spined soldier beetle is red and black and can have cream markings. These immature bugs have no wings, are round shape.

 

The adult two-spotted stink bug is black with yellow or red marking and they are approximately ½ inch long. To see a picture of a two-spotted stink bug adult, click on the following link: <<http://entm29.entm.purdue.edu/acorn/ne.aspx?ne=Two-spotted_stink_bug-_Perillus_bioculatus>>.

The eggs of a two-spotted stink bug are laid in compact double rows containing 18 to 25 eggs on the upper surface of potato leaves.

Like the spined soldier beetle, the immature of the two-spotted stink bug is wingless, round in shape. Unlike the spine soldier beetle, the immatures are colored like the adult.

Who they kill:

The adult and most immature stages of these bugs are predacious. The spined soldier beetle can feed on more than 50 types of prey, primarily the larvae of beetles and moths.

The two-spotted stink bug eats caterpillars as well as Colorado potato beetle eggs and larvae. The two-spotted stink bug prefers smaller larvae than the spined soldier beetle.

How do they kill the prey?

Both spined soldier beetle and two-spotted stink bug have piercing and sucking mouthparts to pierce their prey and suck out its internal body fluids.

 

How to attract them to your garden?
Adults overwinter in the leaf litter of the woods around fields. You may protect them in the winter by providing shelter such as a ground cover, or leaving some crop stubble.

 

Release rate and cost:

Commercial suppliers sell spined soldier beetles. Nymphs are delicate and need to be released soon upon arrival. Eggs are easier to handle but can be eaten by other bugs.
A bottle of 100 immature spined soldier bugs costs about $43.00. Release is 1 to10 nymphs per plant. A card of 250 eggs of spined soldier bug costs about $30.00. No rate was given for the eggs.

 

Should you release spined soldier bugs in your garden and landscape?

The cost of spined soldier bugs is likely to be prohibitive in most gardens. You are better off learning to recognize these insects and try to keep them alive in your garden.

 

Rule of Thumb: It is hard to distinguish the stink bug predators from the stink bug plant feeders. Usually adult green stink bugs are plant eaters, whereas the brown stink bugs are predators.