Natural Defense

Arron Cannon - UNT Geography Major

The honey mesquite tree isn’t the most flamboyant tree in front of the Environmental Science Building on the UNT campus but it is one of the few that has a natural defense mechanism against large mammals. What evolutionary hardship did the honey mesquite endure to develop such a defense, I asked myself? Google helped to clarify the reason behind the tree’s natural defense against large mammals by locating an article that dealt with longhorns in the region. Upon further research I found that it is believed to have developed these large, sharp thorns in defense to large animals either running through a young, more pliable tree or to aid in protection against the tree being used as a sort of “scratching” device, either way I found that particular reason very interesting. Once I got past the thorns I noticed that the bark looked similar to severely dry skin, with deep cracks and breaks showing the younger bark beneath. While inspecting the bark I also noticed a small patch of yellowish moss that was not thriving all over the tree but still alive nonetheless on the branch I was inspecting. There were no other signs of the yellowish moss anywhere else on the tree or even on the trees surrounding the particular mesquite that I was observing. The moss transformed the tree from the niche to habitat, the more I’m susceptible to nature the more I find that this is true over and over again. I also noticed that the tree was not branching out from one large trunk but was instead penetrating the ground surface with a multitude of branches, all independently serving as a trunk for the smaller branches and twigs that were on each protruding branch—characteristics I never noticed before. That particular attribute is not only associated with the honey mesquite tree but a plethora of other tree species. I also found that some, very few twigs, still had tiny yellowish leaves that had not yet falling off yet, strange I though for this time of year. I wrapped up my honey mesquite experience but noticing the dead bark on the ground all around the tree, a natural mulch trapping water from being evaporated around the tree’s base. I’ll now know how to identify honey mesquite tree thanks to this experience.