The question of pecan pollination is important if you want your pecan trees to bear pecans. Since having pecans is probably the reason you planted them, understanding the process will help you make the decision of which ones to plant.
First of all, pecans are wind pollinated. They require no insects to have nuts, just a gentle breeze. Oddly enough, both the male and female flowers are on the same tree but they are not open at the same time. There are a few “self pollinating” pecans that have a short window of overlap of the flowers but they only make a light crop when grown alone.