GONIOZUS LEGNERI FOR
NAVEL ORANGE WORM
POST HARVEST UPDATE
ALMONDS
(August 15, 2003)

With the exception of the cold winter months the Navel Orange Worm (NOW) is growing and reproducing all year long. There is a period in almonds, from hull split until mid-November, the NOW are allowed to reproduced unfettered for several months (absent natural or introduced predators in the field).

Like all insects NOW reproduces exponentially. The astute almond grower looking to reduce NOW populations in the field will see this period of un-interrupted reproduction as a time the NOW can get ahead of him. Trial work done by California Ag Supply has shown introducing Goniozus into the field post Ashake@ of susceptible varieties will substantially reduce the number of infested mummy nuts going into winter. Since control of all insects is a exercise in population reduction. Making sure the NOW does not have a period of un-interrupted reproduction makes sense entomologically.

We recommend the application of 500 to 1,000 Goniozus per acre immediately following Ashake@.(early to mid-September at the latest) to not allow the NOW this period of uninhibited reproduction. Applying Goniozus after October 1 is too late ! There is not enough time period for them to reproduce enough new generations to justify the expense.

This application of Goniozus is in addition to (not substitution for) your normal winter clean up program. If 23% of your mummy nuts are infested going into winter clean up (the non treated area in tests) there is a greater chance of NOW surviving the clean up period than if 6% of the mummy nuts are infested (treated). It is a numbers game.

The closer a grower is to 0% NOW in the field at hull split the better the chance they have of having a clean harvest. Hull split sprays are reported to kill only 50% of the NOW.

We believe the keys to NOW control rest on:

1 - Good winter sanitation !!!

2 - Not allowing the NOW to get too far ahead of you in season.

If the winter clean up was not as good as you like, or your grade sheets showed high NOW damage, then apply Goniozus at 500 to 750 per acre in late March to early April.

3 - Timing your hull split spray properly to have the almonds covered when they dry out and are more susceptible to NOW.

4 - A timely harvest. If you let the dry nuts stay on the tree for a extended period of time they will get infested.

5 - Applying Goniozus post harvest to keep NOW numbers low going to winter clean up.

NOW control is a year round process ! Don=t let this insect get ahead of you !

For assistance or to order Goniozus legneri please contact us.