Description of the Pest
False chinch bug breeds in great numbers in grass or weedy areas, especially on London rocket, and may migrate into vineyards in search for green growth when these areas dry up or are plowed under. Adults are gray and about 0.12 inch long. Nymphs are gray with reddish brown abdomens. When they migrate, they are mainly in the wingless stage, and consequently they migrate by walking. A number of winged adults are also present, but instead of flying they march along with wingless immatures.
Damage
Large numbers of nymphs and adults migrating into the vineyard in the spring, may suck plant juices and inject a toxin that causes vines to wilt and turn brown. Because of the great number of bugs involved and their toxic injections, all the leaves on border vines can be killed in a few hours. September and October migrations are also possible.
Management
False chinch bugs are only a sporadic problem, but occasionally cause rapid and serious damage to young vines.
Cultural Control
If false chinch bugs have been a problem in past years, disc under stands of London rocket and other host weeds about 3 weeks before budbreak in grapevines. Do not delay discing until after budbreak, for it may result in a heavy movement of bugs from the weeds to the vines.
Organically Acceptable Methods
Cultural controls are organically acceptable.
Monitoring and Treatment Decisions
If discing weeds was not done, and high populations of false chinch bugs are found on weeds at budswell or after budbreak, a treatment may be necessary. If nymphs are found moving onto vines, spot treat both vines and adjacent weeds. Bugs migrate mainly in one direction and the wilted vines along the edge of the vineyard will show the line along which they are moving. The insecticides listed below, when applied to the soil in a 30-inch band, can form a barrier to prevent further migration.
| Common name | Amount per acre** | REI‡ | PHI‡ | |
|---|---|---|---|---|
| (Example trade name) | (hours) | (days) | ||
| Not all registered pesticides are listed. The following are ranked with the pesticides having the greatest IPM value listed first—the most effective and least harmful to natural enemies, honey bees, and the environment are at the top of the table. When choosing a pesticide, consider information relating to air and water quality, resistance management, and the pesticide's properties and application timing. Always read the label of the product being used. | ||||
| A. | FENPROPATHRIN* | |||
| (Danitol 2.4EC) | 10.66–21.33 fl oz | 24 | 21 | |
| MODE-OF-ACTION GROUP NUMBER1: 3A | ||||
| COMMENTS: See label for additional requirements regarding hand labor. To protect honey bees, apply only during late evening, night, or early morning when bees are not present. Disruptive to other beneficial insects. | ||||
| B. | MALATHION | |||
| (Malathion 8 Spray) | 1.88 pt | See comments | 3 | |
| MODE-OF-ACTION GROUP NUMBER1: 1B | ||||
| COMMENTS: To protect honey bees, apply only during late evening when bees are not present. R.E.I. is 72 hours for girdling and tying; 24 hours for other activities. | ||||
| ** | Apply with enough water to provide complete coverage. |
| ‡ | Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) 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). |