AUSTIN (KXAN) — This year’s unusual weather included a historic winter freeze, a very wet summer and a dry fall. Those strange weather patterns have an impact on something unexpected: fall foliage.

“In my yard in Austin, the cedar elms all dropped a little bit before now. We have a Post Oak that is now dropping its leaves,” says University of Texas Associate Professor Amelia Wolf Ph.D. Her Wolf Lab at UT studies plant communities and ecology.

Professor Wolf says three things influence when trees will drop their leaves:

  • Day length
  • Temperature
  • Moisture

Since days grow shorter at around the same time every year, Professor Wolf says temperature and moisture are the most unpredictable factors.

“Different trees use different combination of those cues to decide when to start dropping their leaves,” Professor Wolf says. This is why some species may drop leaves earlier in the season than others. Professor Wolf says that this year’s delayed fall is likely a result of the wet summer followed by the dry fall. This month’s record breaking temperatures which have had an impact on wildlife likely did not play as big of a role in the delayed leaf drop.

“It’s kind of hard to pinpoint any single thing, but this whole constellation of factors is kind of leading to what we’re seeing.”

That same unusual weather likely influenced the tree’s color. “Different species respond to different things. I’ve seen some amazingly beautiful, colorful trees around this fall,” Professor Wolf says.

Could this weather impact what we see in the spring?

Professor Wolf says flowering plants germinate in the fall. How they behave now helps determine what we’ll see a few months from now, just like how our wet summer/dry fall influenced the leaves now. Professor Wolf says that germination is going really well. “Especially the bluebonnets are germinating really well, right now.”

“I think it is possible that we will have some nice big flowers in the spring, but it does also depend on what happens for the rest of the winter,” Professor Wolf says.