Remembering to Do Spring Chores before the Summer Solstice Arrives in the Valley

Memorial Day signals a time for us to remember our fallen heroes. It also represents the unofficial start of the summer vacation season.

Of course, we still have a few weeks of spring left before the arrival of the summer solstice. For growers, that means wrapping up spring chores before the hot days of summer. 

Field scout Jenna Mayfield points out that pest monitoring will make the spring-to-summer transition too. For example, the bug du jour moves from peach twig borer to navel orangeworm and mites. Jenna says the cool weather, including a little rain last Friday, kept springtime pests in check over the past week. “They don’t move well in the rain.”

Scale on a branch. (UC IPM photo)

Jenna points out the rain drops shouldn’t cause alarm for almond growers – although those who also farm field crops such as tomatoes are worried about mold. Still Jenna says growers need to keep an eye out for diseases such as scale, which form grayish black spots on leaves, fruit and twigs. Wind or rain will spread the spores of the fungus. Bad cases of scab infection can cause defoliation.

To get through the spring, UC Integrated Pest Management recommends almond growers:

•   Continue monitoring for San Jose scale, navel orangeworm eggs, ant mounds and spider mites.
• Watch for diseases, including alternaria leaf spot, bacterial spot, hull rot, rust and shot hole.
• Assess for weeds.

Use a hand lends to inspect first true leaves in cotton.

Cotton

While almonds had a head start for the growing season, cotton plants are young and developing as the crop moves into its third month of the season. UC IPM says growers should start sampling for aphids, spider mites and thrips as soon as the plants emerge from the ground.

Here’s what to do:

• Sample once or twice a week.
• Walk down rows in four quadrants of the field.
• Use a hand lens to examine the first true leaves or cotyledons of random plants looking for damage and insects and mites.

In general, treating for thrips is only done if plants are showing poor growth. Mites need to be taken care of before defoliation and when the numbers are high. You treat for aphids if high populations continue for a week or more.

Alfalfa

Growers are preparing for the second harvest, or cutting, of the year. Growers monitor for weevils, cutworms and aphids and their natural enemies. UC IPM says thrips aren’t threat to alfalfa and don’t need to be treated with chemical applications.