by Tim Flanigan
The Ruffed Grouse Society was just 15 years old in 1976 when I attended the Society’s annual meeting in Westmoreland County, Pennsylvania. The audience included the “whose-who” of the grouse-hunting community, and the keynote speaker for the meeting was the highly-regarded, Dr. Roger Latham, Ph.D. His word was gospel to outdoor enthusiasts of the time, and rightfully so. Dr. Latham was the Director of Wildlife Management for the Pennsylvania Game Commission and a widely-published outdoor writer. As the latter, he enjoyed great credibility due to his vast knowledge and field experience.
The readers of his Sunday column in the Pittsburgh Press newspaper revered him as a consummate and trustworthy expert on natural-world subjects ranging from wildflowers and mushrooms to grouse, wild turkey and white-tailed deer. Attendees at the gathering knew him to be an avid grouse hunter with extensive upland knowledge that complemented his wildlife biology expertise. The post-lecture Q&A session focused strongly upon the conflict of deer and grouse depending on similar habitats and competing for similar foods.
At the time, a steadily burgeoning deer herd was eating itself out of its proverbial house and home, and grouse numbers were declining due to depleted habitat quality. The critical question was inevitable. “How far would we have to reduce the deer herd to restore good grouse habitat?” One of the attendees asked.
Dr. Latham looked downward for a moment, took a deep breath, raised his head and scanned the anxious audience. “We’d have to practically wipe it out,” he stated, with an air of seriousness that was palpable.
Many in the audience gasped. A rumble of incredulity buzzed through the room. Within seconds, one man responded loudly, “Okay, let’s wipe them out! How do we go about getting that done?” A chorus of like minds and voices quickly chimed in.
Dr. Latham struggled to regain the ardent grouse lovers’ attention and explained the great difficulty in affecting proper deer management.
Like so many aspects of professional wildlife management, managing deer depends on science and social acceptance, and no one realized that more than Dr. Latham did. He recognized a dramatic imbalance between deer numbers and the amount of suitable habitat, yet Pennsylvania’s deer hunters were not ready to accept the science-based solution. His avid promotion of “significant” antlerless deer harvests eventually led to his dismissal as the Chief of the Division of Wildlife Research for the Pennsylvania Game Commission.
“Antlerless deer seasons don’t ruin deer hunting; they merely serve to keep a deer herd healthy and under proper control,” Latham wrote in 1971. His truth ran strongly against public desire.
A decade later, the natural world proved Dr. Latham’s claims about the dependence of grouse and deer upon the viability of their habitat. Claims that were confirmed unquestionably by an insect with a voracious appetite for oak leaves; the gypsy moth. The moth’s historic 1869 escape from captivity in Massachuttes enabled an unstoppable army of forest destruction whose numbers expanded explosively. By 1981, the voracious caterpillars had devoured forest canopies from Maine to New Jersey and Pennsylvania. In my home state of Pennsylvania, gypsy moth defoliation was first recorded in 1960 on 60 acres of northeastern Pennsylvania oak forest. That small spark ignited an amazingly rapid, dramatic and vast change in the state’s overall forest composition.
Like a wind-driven fire that intensifies as it consumes fuel, the ever-expanding hoard of gypsy moth caterpillars steadily gobbled up mature oak forests in a surprisingly rapid progression from the Pennsylvania/New York state line, southward along the Allegheny mountains. Despite man’s best efforts to stop the insatiable horde, thousands of acres became hundreds of square miles of starkly bare forests. The oaks suffered, struggled and died. By 1973, 856,710 acres of oak, ash and maple forests were laid bare.
Man’s efforts to stop the bugs from completely denuding the vast oak forests of Pennsylvania’s woods proved futile. Thousands of gallons of insecticide applied from an army of helicopters proved to be nothing more than a wasted expense. Extensive salvage cutting of veneer logs, sawlogs and pulpwood followed the defoliation as landowners rushed to sell their standing dead trees and avoid a complete loss of their timber value. By 1981, the expanse of defoliated forests totaled 2,528 acres.
The forest died, but its death ignited an explosion of life. Where one giant, sawlog oak once stood, hundreds of new seedlings sprang up, accompanied by all manner of shrubs such as witch hazel, dogwoods, arrowwood and privit. A new forest, pulled by the sun, sprang into vibrant life. The woody stems were accompanied by vast thickets of Hercules club, dogwoods, elderberry, blackberry, raspberry, pokeweed, multiflora rose and a myriad of seed-producing forbs and weeds.
The removal of the canopy that had shaded the forest floor and stifled plant growth empowered an unstoppable force – the life-giving magnetism of sunlight. The speed with which the plant world reacted was astounding. No living forester had ever seen an explosion of plant life on such a grand scale. While humans grieved and anguished over the incredible loss, the natural world celebrated with a vibrant recovery that proved a boon to wildlife. The annual tally of forest defoliation peaked in 1990, with a total of 4,358 acres of bare mountainsides that appeared starkly winter-like in mid-summer.
A new “early-successional” forest burst forth from the suddenly warmed soil and raced toward the sun. The rapid growth of woody stems and soft, mass-producing plants was astounding. Within two years of a salvage cut, the former oak forest became a nearly impenetrable thicket, soo dense with new plant growth that one landowner said, “It’s soo thick in there that you can’t fall. The brush won’t let you fall.” Another noted that he couldn’t recover downed firewood from within his former woodlot because the masses of crushed slimy-stemmed pokeberry acted like grease beneath his tractor’s wheels.
Within these vast and widespread young forests, deer and grouse found paradise-like living conditions, surrounded by dense cover and a veritable cornucopia of wild foods. Both populations expanded to previously unimaginable proportions due to the overwhelming amount of prime cover.
Dr. Latham’s point about forest conditions affecting deer and grouse numbers was proven, unquestionably, but in reverse. Instead of reducing the impact of deer damage to forest habitat by reducing their numbers, nature produced more prime habitat than the deer population could impact negatively. Forest succession is as dynamic as its relationship to forest wildlife populations; both are known and predictable.
Within three decades, forest composition changed dramatically, and wildlife numbers increased significantly. It delighted deer and grouse hunters and stymied wildlife managers.
At the turn of the 21st Century, the moth’s appetite significantly diminished the smorgasbord of hardwood forest foliage. The final tally of Pennsylvania’s denuded forest, calculated in 2018, is an astounding 28,035,986 acres or 43,806 square miles of forests.
Thanks to the widely varied ages of the innumerable timber-salvage cutover areas, grouse hunters enjoyed more than 20 years of exceptional bird numbers and superb hunting action. As the forest matured beyond the early stages so beneficial to grouse, the burgeoning deer population again ate itself out of the home-sweet-home conditions and expanded into croplands and rural lawns. Of course, ruffed grouse could not follow suit into these non-forested realms.
As the forests matured into pole-stage, the leaf canopy shaded out forest-floor foods and cover, resulting in grouse numbers declined precipitously. The years of exceptional grouse gunning were over, and an overabundance of hungry deer consumed much of the remaining grouse-friendly habitat, especially any remaining young oaks. The imbalance had returned.
This historical forest defoliation may never occur again. Still, it proved unquestionably, the exceptional value of early-successional, “young” forests to all manner of forest-dwellers, from warblers and deer mice to ruffed grouse and deer. The natural world is a superb teacher, and we can emulate nature’s forest succession through targeted forest management. Deer, grouse and the chainsaw are a winning trifecta.
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The gypsy moth was imported from France by Mr. E. Leopold Trouvelot, to his Massachusetts home, to breed hybrid silkworms, hardier than the Chinese species, that could establish a silk industry in the United States.
The gypsy moth’s impact enabled a rapid transition of forest types, from mixed-oak to birch and maple stands, which aren’t as beneficial to wildlife as mast-producing oaks. Before the moth, oak forests in central Pennsylvania were producing 173 pounds of acorns per acre; after defoliation, only 67 pounds per acre.
