We learn how to identify a pecan aphid. There a few different types, some more harmful than others. Looking at the leaves closely we see shiny sticky spots on the leaves. This is called honeydew' which is actually the aphids waste. It is not harmful to the tree. The Black pecan aphids however cause brown discolorations on the leaves. They are necessary to control although mother nature offers a way since there are certain insects who actually eat their eggs. It is wise to first consider this method before resorting to insecticide which although can be helpful could be expensive and time consuming.