TY - JOUR AU - Altierr, Miguel A. AU - Schmidt, Linda L. TI - Cover crops affect insect and spider populations in apple orchards JF - California Agriculture JO - Calif Agr Y1 - 1986/01/01 VL - 40 IS - 1 SP - 15 EP - 17 PB - University of California Agriculture and Nature Resources SN - 0008-0845 UR - http://www.ucanr.edu/sites/calagjournal/archive/?article=ca.v040n01p15 AB - Manipulation of cover crops may improve biological control of some pests