Monday, July 9, 2012

Cotton Fruit Staying Put: Could There be a Bumper Crop?




Fireworks weren’t the only things popping last week. With warm summer temperatures, cotton flowers came out in full bloom across the San Joaquin Valley.

Everywhere you look, the lush green cotton fields were ablaze with colorful flowers. The color is even more spectacular this year because of the abundance of bolls still on the plants.  During my travels, I’m seeing cotton plants with a minimum of 80 percent fruit retention. Some even are at an eye-popping 100 percent retention.

I’m starting to think growers could be in store for a very good yield, or bumper crop, this fall. This time of year you usually see plants retaining 60 to 69 percent of their fruit.

National Weather Service June temps for the Fresno-area.
Mother Nature has been very good for cotton growers, providing ideal growing conditions for their plants. We haven’t had a lot of severe, hot weather days over a sustained period of time. In the past month, the average high temperature was 92.8 degrees in the area, according to the National Weather Service. The normal high for June is 92.1.

Green lacewing is a beneficial bug.
Indeed, we recorded only four consecutive days of triple-digit temperatures – although the record-breaking 109 degrees on June 7 was a bit much for late spring. In fact, there were just five days of 100-degree weather last month. Of course, there are still 2½ months of summer left with hot July days on tap (the average high for the month is 98.4 degrees).  Very high heat can be a problem for setting bolls (seed and lint quality) because of pollen sterility. Also, night temperatures of 75 degrees or higher that can affect rest for the plant and hamper energy into developing fruit. But so far, so good.
While lygus numbers are going up, they generally haven’t reached the threshold for treatment. I’ve heard of only two fields being treated locally. Now is the time to keep track of the pest counts and continue to monitor your fields regularly.

A ladybug feeds on aphids.
Right now, cotton is getting its second irrigation. With the plants nice and green, the fields are becoming attractive homes for aphids, especially as nearby tomato, cantaloupe and watermelon fields dry out for the harvest.  The highest count I’ve seen in one field is a 10 percent infestation. It’s no time to be alarmed since the bolls aren’t open and there’s no threat of getting sticky cotton at this time. Beneficial insects such as lady bugs and green lacewings can take care of the numbers at the moment. In a few weeks, I will be releasing beneficial insects to control aphids in fields enrolled in our San Joaquin Sustainable Farming Project. My advice is to keep a close eye on the aphid situation.

Meanwhile, the alfalfa crop is between the third and fourth cutting. I’m spotting some aphids and worms in the fields. My hats off to growers who leaving uncut strips of alfalfa to keep pests from migrating to nearby cotton fields. They earn my “Good Neighbor Award.” Keep up the good work.

Field Days  Ahead: Don’t miss our two upcoming field days in Fresno and Los Banos. Our Almond Field Day is Thursday, July 19 from 10 a.m. to noon at the Rushing Ranch, 11599 W. Shaw Ave., Fresno. Walt Bentley of UC IPM will discuss late-season consideration for insect and mite management in almonds. UCCE Merced’s David Doll will focus on post-harvest practices to reduce disease and pest issues. He also will offer tips about increasing tree productivity and managing water at harvest.

Our Cotton and Alfalfa Field Day is Tuesday, July 24 from 10 a.m. to noon at Bowles Farming, the intersection of Hereford and Bisignani roads, in Los Banos. The speakers are: UC IPM Advisor Dr. Pete Goodell on insects and pests in alfalfa and cotton-managing the crop through mid-season; UCCE Fresno farm advisor Dan Munk on cotton crop development and its impact on pest management; and UCCE and UC Davis alfalfa specialist Dan Putnam on current issues affecting IPM in alfalfa. Directions are available in the events section of the Sustainable Cotton Project’s website – www.sustainablecotton.org.  Two hours of continuing education credits have been applied for at each of the meetings. Both events will be very information. Spread the word.




2 comments: