How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PESTS

Wireworms are the soil-dwelling larvae of click beetles. They resemble mealworms and are slender, elongate, yellowish to brown with smooth, tough skin. The body is usually cylindrical, but flat on the lower side. There are six short legs close together near the head, and the tip of the abdomen bears a flattened plate with a pair of short hooks.

Wireworms may remain in the soil as larvae from 1 to 3 or more years, depending upon the species and the food supply.

DAMAGE

Wireworms feed on seeds and root portions of a wide variety of plants. In corn they can destroy germinating seeds and tiny seedlings. Often the wireworm will be found near the damaged or missing seed or plant. Wireworms will also attack young plants, resulting in weakened plants or a reduced stand. Damage is most likely to occur where corn is planted into a field formerly in pasture or weedy alfalfa.

MANAGEMENT

If wireworms have been a serious problem in the past, a preventive seed treatment or a treatment at planting may be necessary.

Common name		Amount/Acre**	P.H.I.+
(trade name)			(days)
The following materials are listed in order of usefulness in an IPM program, taking into account efficacy and impact on natural enemies. Also consider information relating to water quality when choosing a pesticide.
A.	THIAMETHOXAM
	(Cruiser) 5FS
	MODE OF ACTION: A neonicotinoid (Group 4A)1 insecticide.
	COMMENTS: Use allowed under a supplemental label. Do not apply other neonicotinoid (Group 4A) insecticides within 45 days of planting seed treated with this product. May provide only partial control under high population pressure.
B.	CHLORPYRIFOS
	(Lorsban) 15G	8–12 oz/1000 row ft	Grain or livestock feed: 35
			Grazing or silage: 14
	MODE OF ACTION: An organophosphate (Group 1B)1 insecticide.
	COMMENTS: Apply in-furrow or as a T-band application. The 8 oz rate provides suppression only unless used with a hopper box insecticidal seed treatment.
	** Mix with sufficient water to obtain full coverage.   + Preharvest interval. Do not apply within this many days of harvest.   * Permit required from county agricultural commissioner for purchase or use.   1 Modes of action are important in preventing the development of resistance to pesticides. Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season. For example, the organophosphates have a group number of 1B; chemicals with a 1B group number should be alternated with chemicals that have a group number other than 1B. Mode of action is assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at http://www.irac-online.org/.

PUBLICATION

UC IPM Pest Management Guidelines: Corn
UC ANR Publication 3443
Insects and Mites
L. D. Godfrey, Entomology, UC Davis
S. D. Wright, UC Cooperative Extension, Tulare County
C. G. Summers, Kearney Agricultural Center, Parlier
C. A. Frate, UC Cooperative Extension, Tulare County
Acknowledgement for contributions to the Insect and Mites section:
M. J. Jimenez, UC Cooperative Extension, Tulare Co.

Top of page