Look Out for Almond Pests; Cotton Planting 90% Done

Almond expert Walt Bentley makes a point at our  field day.

For years, long-time entomologist Walt Bentley of the UC Statewide Integrated Pest Management Program has enlightened almond growers across the Valley with his pest management tips.

Walt, who joined Merced County UC Cooperative Extension farm advisor and pomologist David Doll (aka the Almond Doctor), at our almond field day 1½ weeks ago, offers these early season observations  and tips for growers:

Walt gives growers an inside look at a developing almond.

“With the weather we have had recently, almond farmers are going to be more focused on disease management than on arthropod pests.

Certainly the conditions are not there for spider mites to develop into a problem.  As we discussed at our last meeting, there was substantial movement from the ground during bloom.

Pests causing nut gumming problem  in a cluster of almonds.

But the wet weather has resulted in reducing or eliminating these mites.  So, be patient and let’s wait till we find populations in the orchard.  Our last survey in early April resulted in no mite finds in the orchards in the San Joaquin Sustainable Farming program this year.

Both peach twig borer and navel orangeworm are being monitored but the pests are not active. Once it warms, we will be seeing either moths (PTB) or eggs (NOW) in traps.  Currently, it looks like populations will be climbing in early May.

The pests to search for are leaffooted and stink bugs.  These both became active during the last warm spell in early April. However, we didn’t find them or their damage on our survey.  

Leaffooted bugs are becoming active.
- UC IPM photo by Jack Kelly Clark

Leaffooted pests can cause damage early in the season and after shell hardening in June. Nuts damaged during or just after bloom blacken and drop. After hardening, leaffooted bug damage to the meat isn’t obvious. The tip-off is the outside hull will have little ballpoint pen-like marks on it. The damage results in the meat darkening and developing a sunken area and affecting the flavor.

I suggest going to the IPM guidelines at http://www.ipm.ucdavis.edu/PMG and read through the description of the plant bugs.  It gives an excellent guide on insecticides and monitoring.”

It's time to look out for stink bugs.
- UC IPM photo by David Haviland

Thanks Walt your valuable with almond growers. We will share more tips for almond growers in the coming weeks.

From the orchards to the fields: About 90 percent of the local cotton growers have completed planting. Those that already planted a few weeks ago raced to take off the top layer of soil covering the germinating seeds because of the mid-week rain. We had about a quarter inch of rain locally last week.

Cotton seedlings are popping up.

Growers put a “top” over the seeds to aid the germination process. Worried that the rain could make it too muddy for equipment to work in the fields and lead to seed rot, a number of growers moved quickly with their “de-topping” work to allow the seedlings to emerge.  From what I have seen, the seedlings are developing nicely.

In the alfalfa fields, growers continue to irrigate their crop to spur plant growth for the next cutting. During my scouting, I’ve noticed an increase of worms. Growers need to keep an eye out for them in May and June. Beet armyworms develop four generations in the valley and as the eggs hatch tiny caterpillars start feeding on the plant. Cutworms feed on new growth or the alfalfa foliage. You can check the UC IPM website for biological controls for alfalfa pests.