Scouting for Insect Pests, June Edition

Squash Bugs

squashbugweb

Photo: growingsmallfarms.ces.ncsu.edu

Squash bugs, which have overwintered as adults, are actively laying eggs now. Egg clusters can be found on the undersides of leaves. Remove and crush the eggs to reduce the population of squash bugs.

squash_bug_eggs
photo: Whitney Cranshaw, Colorado State University, http://www.insectimages.org

Nymphs and adult squash bugs suck sap from plants and can quickly destroy squash vines. Adults and nymphs frequently hide under damaged leaves and at the base of plants. Keeping debris and mulch away from the base of plants reduces cover for the bugs and may also reduce damage. In fact, Clemson University suggests the following method of trapping adults and nymphs: “The secretive nature of squash bugs can be used to your advantage in controlling these pests. Place a small, square piece of old shingle or heavy cardboard under each squash plant. As bugs congregate under it for protection, simply lift the trap and smash them with your hoe (or shoe).”

http://www.clemson.edu/extension/hgic/pests/plant_pests/veg_fruit/hgic2207.html
http://www.ext.colostate.edu/pubs/insect/05609.html

Mealybugs

mealybug

Photo: ucanr.edu

These pests can be a problem on ornamental plants in the landscape as well as on houseplants. Female mealybugs are oval shaped, soft-bodied, wingless, and covered with a fluffy wax. Males are gnat-like and have wings and a waxy tail. Eggs are contained in a fluffy, waxy mass. Mealybugs feed on sap from plants. They excrete waste called honeydew, which promotes the growth of sooty mold. Small infestations can be controlled by wiping away the insects with a cotton swab dipped in isopropyl (or rubbing) alcohol or nail polish remover or with insecticidal soap.

http://www.ces.ncsu.edu/depts/ent/notes/Ornamentals_and_Turf/flowers/note19/note19.html

Spotted Wing Drosophila

 

on-raspberry-1024x730

Photo: Jesse Hardin, North Carolina State University

The Spotted Wing Drosophila damages fruit crops by cutting a slit into healthy fruit and laying eggs inside. Spotted Wing Drosophila prefers softer fleshed fruits like berries, cherries, and grapes. These insects are less than 4mm in length, and their larvae can be found inside fruit, causing softness and holes.

How can I manage SWD (Spotted Wing Drosophila) in my garden?
While SWD infested fruit may be unpalatable, larvae are not harmful if consumed. Ripening and ripe fruit are susceptible to SWD attack, but flies do not appear to be attracted to unripe fruit. Good cultural management can reduce SWD damage. Good cultural control includes:
1.Excellent sanitation: fruit should be harvested frequently and completely. Any unmarketable fruit should be removed from the field and either frozen, “baked” in clear plastic bags placed in the sun, or hauled off site to kill or remove any larvae present. When you done harvesting for the season, strip any unwanted fruit from plants and destroy it.
2.Canopy and water management: Prune plants to maintain an open canopy. Do not overwater plants. Leaking drip irrigation should be repaired, and overhead irrigation should be minimized.
3.Exclusion: Fruit can be covered with fine mesh bags or paint strainers prior to ripening to exclude flies. Bags should be tightly sealed. Placing a foam plug between branches and the sealed based of bags is useful to prevent plant damage and maintain a tight seal.
4.Regular fruit sampling: Fruit should be observed regularly for infestation before and during harvest.

While cultural control may be sufficient to reduce SWD infestation below damaging levels, insecticides are currently the most effective tool to reduce or possibly prevent SWD infestation. Insecticides can only be applied to plants for which they are labeled. The label is the law! County extension agents and university
specialists can assist with selecting effective, appropriate insecticides. There are some organically acceptable insecticides available for SWD, but they are less persistent than conventional materials and may need to be applied more frequently. (per http://www.ces.ncsu.edu/wp-content/uploads/2013/04/Homeowner-Factsheet-2013.pdf)

http://swd.ces.ncsu.edu/swd-biology/

This video shows how to make a Spotted Wing Drosophila trap to assess the presence of these pests in your garden.

Finally, Japanese Beetles are active. Beetle traps are more effective at attracting Japanese Beetles than controlling them. If you do use traps, locate them far from plants you wish to protect. Per NCSU: Homeowners can take advantage of the beetles’ aggregation behavior by shaking plants to dislodge beetles each morning. Without beetles already on a plant, it is less likely that beetles will aggregate there later in the day. Picking beetles off by hand will also reduce the accumulation of beetles that results in severe damage. They can be easily knocked into a widemouth jar of soapy water.  In some settings, flowers or plants can be protected with cheesecloth or other fine mesh.

http://www.ces.ncsu.edu/depts/ent/notes/O&T/flowers/note44/note44.html