Yellow and black pecan aphids are small, soft bodied insects with piercing sucking mouthparts. Honeydew is the substance that gives pecan trees a shiny glistening appearance during epidemic aphid infestations. Sooty mold often develops on pecans following a heavy aphid infestation.
Yellow aphids are characteristically yellow in appearance.
Shiny, polished, black, parasitized yellow aphids are often confused with the black pecan aphid. Damaging infestations of yellow aphids can cause whole leaves to turn yellow and possibly shed. Black aphid damage is characterized by small, chlorotic areas on the leaflets. Heavy infestations cause rapid leaf shed. Both aphids can cause premature leaf shed, reduced nut quality, and subsequent yield reductions the following season.