I used to worry about all the diseases and bugs that threaten our forests. Right now, the white ashes are dying. Something sinister is killing black walnuts west of the Mississippi and has now been reported in the east. White oaks and the maples are supposed to be under attack too. Out west, fires are laying waste to hundreds of square miles of forest. In some areas here in the east, overpopulating deer are chomping all the newly sprouting tree seedlings. I hear of more gypsy moth outbreaks, which once laid waste to eastern forests for awhile. Seems like bad news all around.
But when I look out the window at the tree grove we live next to, I have a hunch things aren’t as bad as the news sounds. If we did not mow the lawn regularly and did not constantly hoe tree seedlings out of the gardens, we would soon be engulfed by what we have started to call the Green Monster. Even though all the old and medium-age ash trees in the grove are dead, there must be ten thousand new ash seedlings crowding up everywhere they can find a shaft of sunlight. These little trees have trunks about the diameter of a human finger, not big enough for the emerald ash borer to tunnel into, and my bet is that the borers are going to starve out now that they have killed all the older trees. These little ones will come on to make a new stand. That is what happened to the elms. For awhile all the bigger ones died, victims of Dutch elm disease. But seedlings came up and the saplings hung on until they could produce a crop of seeds— which they will do when the trunk is no bigger than 3 inches in diameter. Those seeds sprouted and by the time they got big enough to succumb to the bug that spreads the disease they had dropped another seed crop. Meanwhile with less to eat, the bugs dwindled. The result is that today in our grove there are quite a few elms growing vigorously again.
Our climate is a tree climate and as long as that remains the case, I bet we will always have plenty of trees. Their resilence is amazing. The white oaks drop acorns once every two or three years, thousands of them. The deer feast on them and for awhile I feared that they were eating all the acorns that the worms, blue jays, wild turkeys and squirrels etc. didn’t get. But this year, despite all that predation, hundreds of oak sprouts came up. We mowed the ones in the yard time and again and they grew right back, five times at least before they gave up. Some acorns half-eaten by worms, still sprouted and grew.
The speed at which our hardwoods grow in their early years is also amazing. Clean out a fencerow near a woodlot and it will grow back to jungle in two summers’ time. A mulberry can grow from seed to 15 feet in two years, no problem. I transplanted a kind of shadbush or Juneberry growing in the Green Monster out into the open lawn about 300 feet away so it would get more sunlight. It has blue berries on it that make good pie if we can get them before the birds do. This year I noticed a black walnut sapling about six feet tall growing up inside the bush. I cut it off with the chainsaw. It grew back to the same height again in just three months— only now there were three stems instead of one. Then I noticed two white ash saplings hidden in the bush too, also six feet tall. The nearest seed-bearing ash, now dead, is about 150 feet away.
Jerking some sweet corn for supper, I found a black walnut seedling growing between the corn rows. I guess a squirrel planted it for winter food deep enough so the tiller did not disturb it, but our squirrels must be very forgetful because walnuts are growing up everywhere. So are the other common hardwoods. Oak, mulberry and walnut put down deep tap roots very quickly and hold on for dear life if you try to pull them out. If you cut them off at the soil surface, they pop right back up again. In old Cooper Stadium in Columbus, Ohio, abandoned for about five years now, they say a walnut tree already 12 feet tall, is growing up behind home plate. And in the grand train station in Detroit, one of the largest ever built but now abandoned, the trees are growing through the roof. If you quit mowing or cultivating anywhere woodland grows, the trees will come.