Jack Heikkenen (Herman J.) died last month. He’s studied and taught about bark beetles since before I first met him in 1967. He’s taught me about beetle problems in the US for over 50 years. The New York Times carried an excellent article about apparent new attacks.
Jack’s premise about bark beetles has been that they do not kill trees. The trees are already dead (or more likely dying) from moisture stress. That results, as reported but not emphasized in the Times article, from trees being too close together and either having too much or too little soil moisture. Jack’s major point, especially relevant here at Christmas-tree time, was that pine trees may be dead and still be green. The stresses occur, the tree dies, it later turns yellow … and that is when beetles are noticed and then they are blamed for the loss. The beetles are scavengers like vultures drawn to road-killed deer.
Jack had done studies and was very convincing. More than just an interesting nature story, the significance of the recent article is that these beetle events are not new. They occur in areas where trees are very crowded (as when seeded after a fire). They occur when several stresses gang up – roots are crowded and then a drought. They occur when trees grow beyond the capacities of the soils in which they were seeded.
There are messages from the observed yellowing trees, already noticed by beetles from the pine-like odors emitted: There will be more lightning-caused fires. There will be vast areas of deer and elk forages on the ground now open underneath the leafless trees, thus more big game. There will be new hordes of adapted song birds, especially the insect eaters and woodpeckers for 10 years, then very few of them (no die-offs, only less insect food and nesting sites). There will be another article in 50 years about a vast beetle outbreak, a result of the one now occurring.
The private (and some public) forests have to be actively managed to produce good wood, well spaced, in areas where harvests are feasible and sales profitable. Homes put in forests are risky and owners have to protect themselves and assume the risks. Many acres of public lands are not logged and these need to be viewed as areas where the beetles come and go as the trees grow to a size in which their root structures compete with adjacent trees for water. Then they will be stressed and visitors and other will notice. Locals will understand and not complain, but guests must be taught. Spraying insecticides over vast areas, probably demanded or promoted, is an expensive waste with likely secondary harmful effects, an attack on “vultures” for having killed “the deer.”
The other thing we can learn is that all dead wood need not be moved to a mill at high energy cost. It needs to stay in place, especially in stream channels, to slow the speed of stream flow and erosion, to hold water on the land and move it to groundwater. It needs to decompose and to add structure and nutrition for soil for the new forest … for there will be one. It can be a superior forest under sophisticated modern management.
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Faunal Force is a blog of Bob Giles, Professor Emeritus, Virginia Tech, sharing ideas, observations, and notes on wild faunal ("wildlife") management systems and related topics. His web site is Rural System, part of which provides design for a proposed modern natural resource system. He presents his concerns for the future in his Survivalists blog. He can be reached through Linkedin , Academia, and Twitter.