IN YOUR ORCHARD
TIME TO CONSIDER
Terminal webbing by UC Davis IPM
At the time I am drafting this article, the trees are lush and green. The temperature is in the mid 80’s and water, fertilizer, and sunlight are supporting tree growth. It makes it hard to focus on the future because everything is perfect at this moment. The problem is that when the weather starts to heat up, it will only take a couple days of triple digit heat for a devastating pest to take over. Mites are pests that are often talked about, are difficult to control, and have lasting impacts on your orchard.
There are many varied species of mites that growers may battle throughout the growing season, but in this article, I am focusing on the twospotted spider mite and the Pacific spider mite. These mite species are responsible for turning your orchard into a Halloween decoration in July and August. But how do you know if you are going to have a mite problem ? The best way to know is by monitoring your orchard. Mite populations start small but can quickly explode if conditions are right. High heat, stressed trees, and lack of predators can lead to a flareup of mites in just
a couple days. Those of you who have dealt with mites in the past know that they usually start on a indicator tree or a “hot spot” in the orchard. These spots tend to be stressed individual trees or small stressed pockets found in the orchard that the mites target early on. These trees or areas will give you a starting point to monitor if the population is increasing and spreading, or if it remains localized. Mites are one of the pests you want to identify and monitor early, because trying to play catchup after an outbreak is incredibly difficult. Now that you are monitoring for mites, how do you decide if you should control them or not ? There are miticide treatments that can be made once a mite population has been discovered, but there are two questions that should be asked before an application is made: “What does my predator population look like ? ” and “Is the mite population increasing ? ” In the past, many growers made a miticide application early in May and, initially, this provided mite control for the whole season. The problem is that many miticides are harsh on predators like western predatory mite, sixspotted thrips, spider mite destroyer, and minute
Twospotted spider mite by UC Davis IPM
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ALMOND FACTS
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