Botany: the oak without acorns

Self-tutoring about trees: the tutor mentions an observation that’s confused him, with a possible explanation.

Numerous red oaks grow around here. They are beautiful trees for lining the streets; their leaves turn familiar, attractive colors in the fall as one might imagine. I’ve noticed abundant acorns from some.

Yet, there is one stately specimen of red oak a couple of blocks away which never seems to produce acorns. I’ve looked around it year after year but not found any. I’ve wondered many times why might this be; perhaps I’ve found an answer.

It turns out that oak trees are wind-pollinated. Although they produce both male and female flowers on any given tree (that is, they are monoecious – see my post here), they typically don’t self-pollinate, which is known as self-incompatibility. Therefore, being wind-pollinated, a given oak needs to be near others to get pollinated. Otherwise, it won’t produce acorns.

The red oak that doesn’t seem to produce acorns…I realize it’s isolated from other oaks. Perhaps it’s out of range for wind pollination. Yet, it’s a prosperous tree which I always enjoy visiting.

Source:

internationaloaksociety.org

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.

Leave a Reply