Red Oak Acorn - Genetic Variety

[MilkweedManiac]

I was told once that no question is stupid to ask (including, is this a stupid question?)

Anyway, I’m curious about two Red Oak trees I found growing along a trail about 100 feet apart.
Same bark pattern, and same leaf patterns. Dead give away of a Quercus rubra.

But as you can see pictured, one tree gives a tear drop shaped acorn, while the other gives the common “olive” shape I see so often.

I checked on the ground, and without exception, both trees ONLY dropped one shape of acorn, which has me curious.

1. Is it common for this variation to occur in shape within a species?

2. Could the odd-shaped acorn-producing tree be crossing with another tree? There are some black oaks nearby.

 

[BuckSutherland]

Did you chew on the acorns and see which is less bitter? I think there is lots of crossing going on in the woods.

 

[MilkweedManiac]

Good point. They were both pretty tannic so I didn’t recognize a very big difference there.

 

[Apple Junkie]

That’s an interesting question Milkweed. Within a given species, there is going to be some genetic mixing, so not every red oak is going to be an identical clone of either parent. Leaves of the same species of trees often conform a general pattern, but can vary quite a bit from one tree to another. I am assuming the same can be said for acorn shapes from one red oak to another, and I think that is what you are seeing here. Personally, I don’t think the black and red oaks are hybridizing. Just my 2 cents.

 

[MilkweedManiac]

I appreciate the feedback! The tree with the odd shaped acorns must be an outlier of some kind. As Apple Junkie states, might just be a different shaped acorn due to a different random phenotype. Very cool to study these trees.

 

[OakSeeds]

Red Oaks will cross with other red oaks and whites will cross with other white oaks BUT red and whites rarely - if ever - will cross with each other. :-)

https://www.internationaloaksociety.org/content/hybridization-quercus-seen-through-eyes-enthusiast