When I was in forestry school a few decades ago, there were outbreaks of southern pine beetles in the southeast. At that time it was noted that for some reason beetle outbreaks were unknown in Arkansas. Now such outbreaks have become common. The forest that existed in the pine belt when the Europeans began their expansion was much more open that it is today. This is clear from the earlier explorer's accounts. One could "drive a wagon" through forest, visibility through the forest was a half mile or more. This type of forest had wildflowers that fed predators and parasites of SPB. Apparently it was also more favorable to the RCW. This type of open forest existed until the 1920's or so. Perhaps the frequency of SPB outbreaks are a consequence of the more dense forest stands that are now maintained and the value of the RCW is the cost of these outbreaks. It may be that the RCW was a significant predator of the SPB or its favored habitat was not conducive to SPB epidemics.
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