Influence of Four Ground Cover Vegetation Types Used in North Carolina Fraser Fir Christmas Tree Plantations on Abundance and Species Composition of Phytoseiid Mites (Acari: Phytoseiidae)

A study was conducted to determine the utility of ground cover vegetation in managing the natural enemies of spruce spider mite (Oligonychus ununguis Jacobi) in Fraser fir production areas in 2 locations in North Carolina (Laurel Springs, Waynesville). Predatory phytoseiid mites were sampled by collecting vegetation from 4 ground cover species in experimental Fraser fir plots: white Dutch clover (Trifolium repens L.), mammoth red clover (Trifolium pretense L.), birdfoot trefoil (Lotus corniculatus L.), and fescue (Festuca spp.). The most abundant phytoseiid mite species were Typhlodromips sessor(DeLeon), Arrenoseius morgani(Chant), Proprioseiopsis solens (DeLeon), and Typhlodromalus peregrinus (Muma). There were no statistical differences in the effects of ground cover vegetation on phytoseiid mite abundance or diversity.