Description of the Pest
Gum exuding from around the base of the trunk is evidence of a peachtree borer infestation. Larvae of the peachtree borer are white with brown heads. Adults are clear-winged moths with blue-black bodies that have yellow or orange bands across the abdomen. The adult peachtree borer may be found from June to September, with larvae present in the tree the rest of the year. There is only one generation each year. It is found mainly in coastal areas and in the northern San Joaquin Valley.
Damage
This wood-boring insect can successfully attack healthy trees. The larval stage bores into the crown and trunk of the tree and mines the cambial layer. If this occurs for several years, the tree may eventually become girdled and die.
Management
Apply insecticides when adults emerge to help control peachtree borer adults. Pheromone traps are available to monitor adult emergence.
| Common name | Amount to use** | REI‡ | PHI‡ | ||
|---|---|---|---|---|---|
| (Example trade name) | (conc.) | (dilute) | (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. | ESFENVALERATE* | ||||
| (Asana XL) | 4.8–14.5 fl oz | 2–5.8 fl oz | 12 | 14 | |
| MODE OF ACTION GROUP NUMBER1: 3 | |||||
| COMMENTS: Apply as a directed trunk and scaffold limb spray. Thorough coverage of trunk and scaffolds is required. | |||||
| B. | ENDOSULFAN* | 2.66–3.33 qt | 0.66 qt | 4 | 7 |
| (Thionex) 3EC | |||||
| MODE OF ACTION GROUP NUMBER1: 2A | |||||
| COMMENTS: Apply with a hand spray gun to tree water or trunk from juncture of main scaffold limbs to soil line. Cover trunk thoroughly using enough liquid so it runs off to form a small puddle at base of tree. Two treatments are necessary to span the long emergence period of this insect in California. Make the first in mid-May, the second in mid-July. Hoe around trees to remove weeds or sucker growth that might interfere with spray coverage. Clear away any excess soil piled against tree during discing operations. | |||||
| * | Permit required from county agricultural commissioner for purchase or use. |
| ** | For dilute applications, rate is per 100 gal water to be applied in 300-500 gal water/acre, according to label; for concentrate applications, use 80-100 gal water/acre, or lower if the label allows. |
| ‡ | 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. |
| 1 | Rotate pesticides 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; insecticides with a 1B group number should be alternated with insecticides that have a group number other than 1B. Mode-of-action group numbers for insecticides and miticides (un=unknown or uncertain mode of action) are assigned by IRAC (Insecticide Resistance Action Committee). |