Growing Season Moving Along Without Any Big Hiccups

Haystacks are being collected.

Second cutting of  alfalfa is complete.

While the weather has been a little unpredictable this spring, the growing season has been rather predictable in 2012. So far, there have been no major surprises.

Spider mites are starting to increase.
- UC IPM photo 

Around the Valley, alfalfa growers have wrapped up their second cutting without a hitch. On the pest front, I’ve been seeing an increase in alfalfa loopers. These bugs show up in May and early June and feed on the leaves. However, loopers are seldom a threat because they are usually kept in check by natural enemies. In fact, there has been a good increase in beneficial insects, including lots of big-eyed bugs and minute bugs as well as green lacewings.

Aphids also seem to be under control. Growers are timing their cutting to control this pest. By timing the cutting when aphids are on the rise, you end up getting rid of an entire generation of aphids.

Alfalfa loopers usually aren't a threat.
- UC IPM photo

During my visits to cotton fields, I am noticing issues with spider mites, which can suck out the cell content from leaves. Some growers are mulling over the idea of treating for mites based on their earlier assessments in the field. However, I suggest growers do another check of their fields before going ahead and treating for the pests. You might find the beneficials such as minute pirate bugs and big-eyed bugs are providing adequate biological controls to reduce the infestation and saving the expense of treatment.

Minute pirate bug  is a good bug.

For example, the infestation might have been 25 percent during a previous field check. If you go out again just before applying materials, the infestation may be down to 6 to 7 percent thanks to beneficial insects keeping them under control. You want to avoid “revenge treatment.” Translated: You may gain a certain amount of personal satisfaction from treating the field, but the move may not give you an economic return because the pests have moved on.

So before going ahead with treatment, check with your pest control advisor and take a closer look at the plants by doing leaf counts for mites.

Field Day Alert:  Don't miss our June 12 Cotton Field Day featuring UC IPM advisor Dr. Pete Goodell and UCCE Fresno County cotton specialist Dan Munk. They will offer valuable tips for early season pest and agronomic management during the 10 a.m. to noon event at the Housley and Vandenberg Farm on Sierra Avenue in Firebaugh. Directions are available in the events section of the Sustainable Cotton Project’s website – www.sustainablecotton.org.  One and a half hours of continuing education credits have been applied for. Bring your questions and invite a fellow farmer.