High temperatures and low rainfall can help make for a great vacation destination. But when the tourist hordes turn out to be mites descending on your almond orchards, trouble is sure to follow.
Due in part to the hot and dry conditions seen in the lower half of the San Joaquin Valley this spring, we’re already seeing spider mite infestations in some almond orchards. It’s quite possible that this could be a very heavy year for mite pressure, and that’s bad news for the unprepared grower.
Spider mites extract nutrients from the leaves of almond trees, causing leaf stippling, discoloration and, ultimately, leaf drop. High populations can cover trees with webbing and lead to future reductions in crop size and vegetative tree growth.
Managing mite populations is all about being proactive. As soon as you see mite populations building, consider applying a miticide such as Zeal® from Valent U.S.A. Corporation. Zeal provides long-lasting control of two-spotted spider mite, Pacific mite and red mite through a novel mode of action (MOA) that even controls mites resistant to other chemistries.
Most almond growers from Fresno to Bakersfield, where mite populations are historically highest, make two miticide applications per season—one in early May, and another at hull split using a different MOA.
The first spray, which will ideally provide 6–8 weeks of control, should be applied early in the season, but not too early. This is because almond trees—especially younger and non-bearing trees that are being encouraged to grow quickly—may outgrow the residual protection.
For the second spray, applying a translaminar miticide such as Zeal at hull split provides protection by moving through the leaf and reaching mites where they hide, under the leaf. As temperatures continue to rise during the summer, you’ll already be protected.
In addition to miticide applications, cultural practices can help limit mite infestations.
Because mites travel on dust particles scattered in the wind, it’s important to keep roads watered and limit field traffic in order to keep dust down. One way to do this is by mowing every other row middle rather than all of them at once, since clean rows reflect more ground heat.
Also, make sure the orchard is well hydrated so trees aren’t stressed for water at times when there are mite infestations in the vicinity.
To learn more about Zeal and the rest of Valent’s portfolio of tree nut products, visit www.valent.com/zeal.