This demonstration site continued, for a fourth year, to
serve as a central focal point for the Almond Pest Management Alliance project
in the Sacramento Valley. The
orchard will continue to demonstrate reduced risk practices and pest levels were
again compared across five treatments.
These treatments consisted of a grower standard, a reduced risk, an
organophosphate applied in the dormant season, an organophosphate applied during
the dormant season and again at hullsplit, and a no spray treatment which was
added for this growing season.
The demonstration site is 49.5 acres with a division
splitting the block into a 27 acre western block and a 22.5 acre eastern block.
The 27 acre block was managed using the current techniques practiced by
the grower with ½ acre set aside as an untreated check.
In the 2000-2001 season it turned out that the grower did not use any
sprays in the grower standard, so the management of the ½ acre check was the
same as the whole 27 acre block. Of
the 22.5 acres, 12.5 acres was managed using a reduced-risk strategy which
included a Bt spray at bloom. Of
the remaining 10 acres, five acres received a dormant organophosphate
application, and five acres received a dormant organophosphate as well as an
organophosphate hullsplit application.
Monitoring and sampling for evidence of insect pests continued as before. Of the numerous sampling methods used, none showed any more pest problems or damage in the reduced risk or no spray treatments as compared to the OP treatments. Some of the methods used to reach this conclusion were: 1) Dormant spur sampling: Spurs were collected from each treatment block and inspected for mites, San Jose Scale, Peach Twig Borer, and European Fruit Lecanium. 2) Mummy counts: Average number of nut mummies remaining in trees tabulated for each treatment. Mummies are an overwintering site for NOW. 3) Trap counts during the growing season: Traps for SJS, PTB, and NOW placed in each block and trap catches counted weekly. 4) Harvest sampling: 500 nuts collected from each treatment at harvest, inspected for damage, and the damaging insect identified. In addition, a satellite project was created in an area with pressure from European Fruit Lecanium. The project consisted of three treatments, an untreated check, and oil spray at two different timings. Monitoring showed that parasites were controlling the EFL and no additional sprays were needed in any of the treatments.