A UC Davis paper, authored by Bentley and others, advises that nuts should be harvested when 100 percent of the nuts are at hull split at the 6-to 8-foot level in the tree canopy. If susceptible nuts are harvested before third-generation eggs are laid, sprays are not needed.

Egg traps and degree-day calculations can help track NOW development. More information on this is available online at http://www.ipm.ucdavis.edu/WEATHER/index.html

 For orchards which are properly sanitized and where early harvest is achieved, insecticide applications are not usually needed, unless there is a source of moths from infested trees outside the orchard, according to the UC Davis report.

Mummy nuts should be removed from orchards before bud swell by mechanically shaking the tree or by hand poling. The end result should be less than two mummies per tree by Feb. 1 in the Sacramento Valley and even less in the SJV.

The report says blow or sweep fallen mummy nuts to the row center for destruction by disking or flail mowing by March 15 where ground cover is not present.

According to the UC report, moist orchard floor conditions provided by winter vegetation and rain enhance the mortality of NOWs in mummy nuts which have fallen from the trees.

It is important to sample almond orchards on or before Jan. 15 for mummies to determine if further shaking is needed. Examine and count overwintering nuts on 20-trees-per-block to obtain an average.

A spring spray program can still be effective, Bentley says. Timing is critical on the applications since each spray is life-stage specific to the developing insects.