Bruce Kreitler: Trees are made to withstand wind

Bruce Kreitler
Special to the Reporter-News
Bruce Kreitler

I don’t know if this winter has been unusual in how high some of our wind speeds have been, after all these years, winters kind of run together.

However, I think it's safe to say that we've had some pretty impressive winter winds this year, whether they have been "business as usual" or not. Frankly, anytime the winds are gusting to nearly 60 mph, I consider that to be real wind. 

One thing about wind is that it exerts extreme force on anything, such as trees, that may be blocking moving air. The way trees move around in high winds may look impressive from the ground (because it is), but one time actually being up in a tree's canopy while high winds are blowing will really show how much force wind puts on a tree.

Take my word for it, it's pretty impressive. If you try it, don't put any parts of your body between branches that are close to each other (unless those body parts happen to be spares).

So, with the recent high winds, why wasn't the ground littered the next day with the bodies of trees that were unable to stand the force applied to them? Good question.

Wind puts an incredible amount of "push" on a tree, and it wouldn't be unreasonable at all to anticipate 60 mph winds mowing down the local forest. The reason that our high winter winds don't blow down our large, woody-stemmed, plants is that the angels of tree preservation have given us special dispensation because we're West Texans, and just deserve it.

Well ... maybe that's not it.

The windstorm that we had a few weeks ago was pretty intense, and while it did some damage to trees, it wasn't very much. The reason for that is that when those winds blew through, very few of our deciduous trees (trees that drop their leaves in the fall, and re-grow them in the spring) had leafed out yet. Even now, there are not a lot of new spring canopies full of foliage.

Yes, there is blooming going on, and some trees are starting to put out leaves, but the majority of the deciduous trees still are mostly leaf free, and that reduces the surface area that wind has to work on. Having said that, and offered a reason that our deciduous trees were relatively unharmed, what about our evergreen trees?

If the difference between damage, or not, was whether or not a tree had leaves, how come the evergreens are still standing?

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Could it be that the reason deciduous trees are deciduous is because they just can't stand winter winds, and dropping their leaves is how they avoid becoming wind thrown? No, that's not it.

Deciduous trees are more worried about the availability of usable moisture in the winter than they are about winter winds. Besides, we get some pretty intense spring winds also, and those happen when trees are leafed out for the year. 

The reason that evergreen trees hold up so well to high winter winds is that being able to do so is a survival characteristic. Those trees are fully foliated for nearly every weather event, be it wind, snow, ice or some combination of those. Because of that, their response is to grow strong in reaction to those external forces.

Essentially, our high winds "exercise" our trees, and they grow stronger because of it. This works even for our deciduous trees, but they just don't get quite as much of that exercise as the evergreen trees do.