Fall fell with a “thud” this weekend after two nights of subfreezing temperatures.
The green ash tree in my front yard went from fully leafed to fully bare branches seemingly overnight due to two days of unseasonably cold temperatures.
On Friday morning, after the first night of subfreezing temperatures, I went outside and leaves were falling like rain from many of the uppermost branches and the lawn was covered with a thick layer of green leaves.
On Saturday morning, after the second night of subfreezing temps, the tree had but a few leaves on its lower branches. All of the other leaves had landed beneath the tree in a perfect circle just outside the outer edge of its canopy.
Of course I was immediately concerned with the health of this 25-year-old tree, especially after reading recent reports of a looming ash tree crisis.
However, a quick glance up and down the block showed every green ash tree had experienced the same sudden leaf drop. Other trees, like the silver maple and white ash trees in my yard, retained their leaves.
The native ash tree is facing extinction in the U.S. because the emerald ash borer is nibbling its way across the country. The larvae of these beetles cause extensive damage because they eat through the tree’s tissue, reducing its ability to take up water.
Scientists across the Midwest are in a mad scramble to collect seeds from ash trees to prevent the ash from suffering the same fate as the Dutch elm and American chestnut.
Seeds are are now being collected for preserving to repopulate the landscape if the ash borer is successful in its efforts and if scientists find a way to eliminate the emerald ash borer or control the damage it causes.
Some of the collected seeds will be stored at the National Center for Genetic Resources Preservation in Fort Collins.
I didn’t see Colorado on the list of states where this harmful pest has already caused so much damage. It’s reported that millions of trees in 13 states have already died.
With the natural challenges our trees have to cope with throughout the year, including extreme temperature fluctuations in fall, they certainly don’t need any new problems to threaten their survival.