Predatory mites can provide consistent biological control of pest mites such as the European red mite (Panonychus ulmi), (ERM), and two-spotted spider mite (Tetranuchus urticae), (TSSM). Pure or mixed populations of several predatory mites occur in New York tree and small fruit plantings. The most important of these predators are the phytoseiids Typhlodromus pyri and Amblyseius fallacis. Metaseiulus occidentalis, another phytoseiid, is capable of controlling pest mites, but it occurs only sporadically in New York orchards. Its behavior as a predator is similar to A. fallacis. Zetzellia mali, a Stigmaeid or yellow mite, can be found in almost any orchard in the state, but provides biological control by itself only when ERM numbers are relatively low.