Presently, the citrus industry of northeast Mexico is at the risk of invasion by the brown citrus aphid, Toxoptera citricida Kirkaldy (Homoptera: Aphididae), a pest that invaded the south of Mexico during February 2000. In order to favor the abundance and diversity of indigenous natural enemies that could attack invasive populations of the pest, we evaluated food sprays in young citrus trees, and weed management practices in a mature citrus orchard. Food sprays included brewer’s yeast (Saccharomyces cerevisiae)+sugar, baker's dry yeast+sugar, powder milk+sugar. Weed management included the following treatments: a) control (no weeds), b) weeds allowed only under the canopy of the trees, and c) inter-row presence of weeds. In comparison with the control (trees sprayed with 1 l of water), trees that received the treatment based on powder milk (5 g)+ sugar(5 g) in 1 l of water/tree showed in the leaves significant high number of chrysopid eggs and larvae (mainly Chrysoperla rufilabris (Burmeister) and Ceraeochrysa sp. nr. cincta (Schneider) [Neuroptera: Chrysopidae]). Plots with weeds, either under the tree or in the inter-row area had a significant presence of spiders (Araneae: Araneidae, Salticidae, Tetragnathidae, Thomisidae) as well as beneficial insects (Chrysopidae and Coccinellidae) (P>0.01). Spiders were notably abundant in the trees (>6 times the number of beneficial insects). Citrus yield was not reduced by plant competition. In northeast Mexico, weed management in citrus orchards should consider that the abundance and diversity of beneficial arthropods associated with the presence of wild plants could contribute to the control of T. citricida.