Northern Red Oak with Male flowers

Here is a photograph of  Northern Red Oak leaves in May with Catkins (male flowers). When meandering around Vernon you most certainly are going to see oak trees as they are abundant here. I found this oak tree by Newton road. But how did I know that I was taking a picture of  Northern Red Oak leaves?

Identifying oaks by their leaves is at first like a yes or no elimination test. Because oaks are sorted into two groups the white and the red or black oaks; knowing that oaks either have rounded leaf lobes without bristles or sharp lobes with bristles will eliminate an entire group of oaks.

Our white oaks include: White, Swamp, Chinkapin, Burr, and English.  These oaks have rounded leaf lobes (the part of the leaf that comes out from the mid-vein) and no bristle on the end of the lobes.

Our red or black oaks include: Northern Red, Black, Scarlet, Shingle and the Pin. Red or black oaks have (with the exception of Shingle Oak) sharp lobes, and all have leaf bristles. If it does not have lobes but does have bristles at the end of the leaf it might be a Shingle Oak. Ours however has deep lobes and so is not a Shingle Oak.

Okay, so the oak in question  falls in the red or black oak group because its leaf lobes are sharp with bristles.

The next task is to fold the leaf over along the mid-vein. From side to side is the leaf equal? Looking at the photograph below, notice that if folded, our leaf would not be equal. Pin Oaks folded in half are equal (you may want to try this with  a few different leaves.) This is not a Pin Oak.

Next turn the leaf over. Look at the base of the leaf along the mid-vein. Is it fuzzy along the mid-vein? No need to guess here as the fuzziness is very noticeable. Our leaf is not fuzzy and so it is not Black Oak.

Could this be a Scarlet Oak? Scarlet Oak leaves have a distinctive "C" shaped or open sinus (between the lobes dipping towards the mid-vein.)  Our leaf is not a Scarlet Oak.

So it seems that by the process of elimination, our oak is a Northern Red Oak. Its color is a dull green on both top and bottom and it has between seven and eleven bristle tipped lobes. Another way to confirm your decision is to look around the base of the tree for an acorn cap which will persist for about a year. The Northern Red Oak's acorn cap is shallow, covering roughly one fourth of the acorn. Also when looking upwards at a mature Northern Red Oak tree's bark there are flattened lighter colored "ski trails." -Norma Manning