One of the most common questions we got in Extension Offices across the state of Wyoming
in the winter of 2015 was, “how come all of the evergreen trees are brown and what
happened?”
People thought that they had anything from a disease to the fact that they might have
dried out for the winter or maybe they even had insect problems.
The problem actually happened back in November when we went from 50s and 60s as far as daytime
temperatures down to a night where we went to minus 27 in some areas of the state.
That cold change caused ice crystals to form in the cells of the needles and as those cells
formed those ice crystals, they ruptured and died.
Some of our species, like the Blue Spruce here, had no problem with it because they
have an extra heavy waxy coating on the needles.
Some of the plants that were affected most were our Junipers either in the tree form
or the shrubby ones and some of our Pine trees.
We’ll just have to wait and see if the new growth on those trees begins to grow this
spring.
If we don’t see any of that new growth occur on our evergreen trees by the first to the
fifteenth of June, we may find that we have to remove trees.
The best thing you can do to improve the situation for these trees, or to help them make it through
the winter is to make sure that the trees are well watered.
So you do need to do winter watering and continue to water into the spring season.
For the University of Wyoming Extension, I’m Donna Hoffman, and you’re watching From
the Ground Up.