Now, it's the time to begin mite sampling in almond orchards. Knowing population level of mites and their predators is very important for making management decisions. Here I am talking about webspinning spider mites (twospotted, Pacific, Strawberry), high population of which can cause economic damage to almonds. Not all level of infestation warrants miticide application. The high predator-mite ratio is beneficial and often sufficient to keep the damage below the acceptable level. Western predatory mites, six-spotted thrips, spider mite destroyer (a black color lady beetle) are the known predators of the spider mites in almonds. Western predatory mites seems to be a good player during early part of the summer, while six-spotted thrips are abundant later in the season. Application of any broad-spectrum insecticides (e.g. pyrethroids, organophosphates) kill natural enemies of pest mites. Consequently, mite population increases exponentially. Selection of pesticides for other pests such as navel orangeworm, peach twig borer should be made in such a way that it is not detrimental to the predator population. Details about when and how to do spider mite sampling and what control options are available can be found in my recent article published in the 'Field Notes' newsletter. See my article here.
Fig. Western predatory mites (clear color) feed on spider mites (green with black spots) and eggs
Fig. Spider mite destroyer larva
Fig. Spider mite destroyer adult
Fig. Sixspotted thrips adult