Northern red oaks have leaves with 7-9 pointed lobes with v-shaped sinuses (the indented part between the lobes). Young leaves are often pinkish red and hairy. The bark of the Northern red oak is distinctive with long ridges. The fruits is an acorn. There are frequent hybrids between the northern red oak and other related oaks. For the purpose of this study, you can include any oak tree that reasonably fits the above description as long as the leaves have pointed lobes.
There are three different ways to identify the three species of oaks:
Leaves: Red and black oaks have leaves with pointed lobes and white oaks have leaves with rounded lobes. Red and black oaks have highly variable leaves, but red oaks usually have 7-11 lobes and are somewhat dull on the upper surface compared to the black oak which has leaves with 5-7 lobes and is more shiny on the upper surface.
Bark: The bark of red oaks is dark and forms long, thin strips with rough shiny edges. Black oaks have dark bark that forms block shapes without ridges. White oak bark is light gray and often scaly.
Buds: Red oak buds are hairless and can be pointy or blunt. Black oaks buds are gray and hairy. White oaks buds are small, reddish brown, and blunt.