Ask Mr. Smarty Plants

There are several reasons that a tree can lose its bark.  These include mechanical trauma and environmental stress that can weaken the tree's resistance to infestations by insects, bacteria and fungi.   In urban/suburban settings it is usually physical trauma (e.g., scraping the tree trunk with the lawnmower or striking it with the string of a weedeater) that results in bark missing from trees.  Physical trauma caused by deer rubbing their antlers on trees can happen both in urban/suburban settings and in the wild.  Some of the missing bark you see in the woods is probably due to deer rubbing their antlers to remove the velvet and to establish their territory and attract mates. Other animals (squirrels and other rodents) will also eat tree bark.  Additionally, the extreme heat combined with drought conditions certainly have had an adverse effect on the health of all vegetation.   The NOAA Little Rock website shows your county (Carroll County) in northwest Arkansas as abnormally dry in 2011, but not in extreme drought.  In Texas, not only did we experience extreme heat but also extreme drought.  Your temperatures were certainly high, but again not as high an average as those here in Central Texas. It is reported that 10% of the trees in Texas have died because of the extreme drought and heat. 

So, in answer to your question, if your area has a high deer population, that could explain at least part of the loss of tree bark.  There is no doubt, however, that the extreme heat and dry conditions have stressed the trees all over the southwest this summer causing disease and death.

Here is information (Trees: Damage) about problems with trees and expected outcomes from North Carolina State University and information (Drought, Wildfire and Forest Health) from the Texas Forest Service.