Frans Fontaine Hornbeams - Holding Green Leaves - November 2022

Almost everything but our large, mature Northern Red Oak trees have dropped their leaves this season and have begun their long Winter's nap.  I say *almost* because there's one big outlier:  Our Frans Fontaine European Hornbeam trees.  Not only are they still holding their leaves....they're still green.  See below for a photo of the current state - during the first week of November - of what these trees look like.  You'll see some yellow here and there, but there's a remarkable amount of green foliage: 

The most recent check-in on these trees (with photos) was during their peak in early Summer - July of 2022 - when they were alive and lush.  

I documented these trees on December 1st of 2021 when they were still clinging to *some* of their leaves, but they were all dry, desiccated and brown.  Will these stay green until December?  Not a chance, right? 

But, the trees (this year) are MATERIALLY DIFFERENT than what they showed in 2020.  Here's a photo from November 11, 2020.  Four days shy of two years ago.  And, the trees were see-through with very little foliage and one of them was completely naked.  By November 24th of 2020 (basically 2.5 weeks from now), all of the trees were naked and every leaf had dropped.  

So, what's different?  I'm not sure.  But, I have been watering these in all Fall.  At least once-a-week, I run the soaker hose for >60 minutes on the roots.  That may be helping?