As fall progresses blackberries, blueberries, and beetles diminish in the diet and acorns and beechnuts increase until they become the primary sustenance. Bears are particularly fond of white oak acorns, the sweetest. In their eagerness the huge animals, which sometimes reach 200 kilos (450 pounds) in weight, even climb trees and crawl out on the branches as far as they can to eat the fruits or break off and drop the branch tips for consumption on the ground. They also relish black cherries and serviceberries. A park naturalist told me of watching a very large bear climb a 5-centimeter (2-inch) thick serviceberry on Spence Field, bending the tree double. Throughout the Southern Appalachians you can see small serviceberries broken down like this by bears in their quest for the fruits. In most years the mast crop is adequate for all the animals dependent on it, but in the years of failure bears are hard pressed to find enough to eat. They wander down out of the mountains in search of food. In such years many are killed by hunters outside the national park. The loss of bears in some of the poorest mast years may be one-third to one-half of the park’s bear population. Enter now the European wild boar. Its history in the Smokies is another classic example, along with the chestnut blight fungus, balsam woolly aphid, Norway rat, Starling, and a host of other pests, of the damage that can be done by introducing an organism to territory outside its normal range. The wild boars in the Smokies are believed to be descendants of animals, purportedly of stock from Germany, that escaped from a game preserve on Hooper Bald, southwest of Fontana Lake, in the early 1920s. They were first detected in the park about 1950. By the early 1960s wild boars, now with some admixture of domestic pig blood, had spread east to Newfound Gap and, in the lower country, to Cosby and possibly Cataloochee. Their occupation of the entire park seemed imminent. So now the Smokies have a wild counterpart of the domestic hog, the staple livestock animal that mountaineers once ran year-round in these woods. Horace Kephart’s vivid description of the hog in the 1920s applies almost as well to today’s European wild boar: “In physique and mentality, the razorback differs even more from a domestic hog than a wild goose does from a tame one,” Kephart wrote. “Shaped in front like a thin wedge, he can go through laurel thickets like a bear. Armored with tough hide cushioned by bristles, he despises thorns, brambles, and rattlesnakes, alike. His extravagantly long snout can scent like a cat’s, and yet burrow, uproot, overturn, as if made of metal.” The hog’s long legs, thin flanks, and pliant hoofs fitted it to run like a deer and climb like a goat, Kephart claimed, calling it “a warrior born” who was also a first rate strategist.