How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PESTS

The potato flea beetle is a small (0.065 inch), shiny, black beetle. The threespotted flea beetle is two to three times larger and has an orange colored thorax on which are three prominent dark spots. The palestriped flea beetle is about twice as large as the potato flea beetle. It is dark brown and has a longitudinal creamy white stripe on each wing cover. The desert corn flea beetle is 0.125 inch long and brownish with two pale yellowish stripes along the wings.All of the flea beetles have enlarged hind legs and jump vigorously when disturbed, thus the name flea beetle.

DAMAGE

Damage is caused by adults. Feeding by the potato, palestriped, and threespotted flea beetles consists of numerous small rounded or irregular holes eaten in leaves so that leaves appear to have been peppered with small shot. Feeding by the desert corn flea beetle causes yellowish white feeding scars about 0.125 to 0.5 inches long along the leaf veins.In young plants particularly, the feeding damage can be very serious and can result in death. In addition to adult damage, larvae of the palestriped flea beetle feeds on roots of young plants as well as on germinating seeds.

MANAGEMENT

No economic thresholds are available but treatments, especially on young plants, should be considered if damage reaches a moderate level. Keep fieldsweed-free, particularly of field bindweed and mustard, which are preferred hosts of flea beetles. Heavily damaged fields should be replanted.

Common name		Amount/Acre**	R.E.I.+	P.H.I.+
(trade name)			(hours)	(days)
The following materials are listed in order of usefulness in an IPM program, taking into account efficacy, information related to natural enemies and honey bees and environmental impact. Not all registered pesticides are listed. Always read label of product being used.
A.	CARBARYL*
	(Sevin) XLR Plus, 4F	1–1.5 qt	12	Sweet corn: 2
				Forage: 14
				Grain or fodder: 48
	MODE OF ACTION GROUP NUMBER1: 1A
**	Mix with sufficient water to obtain full coverage.
+	Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (P.H.I.) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.
*	Permit required from county agricultural commissioner for purchase or use.
1	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 to help prevent the development of resistance. 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 Group numbers are 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 Insect and Mites:
M. J. Jimenez, UC Cooperative Extension, Tulare County

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