In the last four issues of this newsletter, I have outlined methods to rehabilitate forests to achieve a more healthy ecological condition, using disturbance forests (ones that grow in on open ground) as a canopy to maintain the damp, shady ground conditions that favor the regeneration of original Acadian Forest species like hemlock, white pine, sugar maple and yellow birch.

Young disturbance forests also lack a broad range of wildlife habitats found in natural woodlands. For one thing, they have few or no trees with holes or cavities where creatures from mice to black bears can take refuge, and where species like flying squirrels and yellow-shafted flickers usually nest.

The last two species will serve as cases in point for this article, because their presence adds significantly to the ecological health of the forest.

Scientists discovered recently that flying squirrels can play an important role in ecologically healthy forests. By eating fungi (mushrooms) while travelling through forests and dropping the fungi's reproductive spores in their scat (poop), northern flying squirrels spread a number of mushroom species. Threads of fungi live on the root systems of trees, where they help to convert and supply nutrients that trees need. So forests with tree holes or cavities that shelter flying squirrels can contribute wider ecological benefits for the woods as a whole. Clearcuts quickly end that relationship.

Yellow-shafted flickers (a brown woodpecker with a white rump) spend a great deal of time probing in the ground with their beaks, where they unearth and eat enormous quantities of overwintering insects - like codling moths and other species that pupate in the soil under apple trees. In one meal a flicker can consume as many as 5,000 ant eggs, larvae and ants. I love to see them spending time in the orchard as well as the woods.

If you want species like flying squirrels and yellow-shafted flickers to inhabit your woods, but the existing trees are not old enough to have developed sufficiently large holes, you can build and erect nest boxes as an interim measure. Thirty-plus years ago, I put up a variety of sizes of nest boxes in appropriate places to attract different species. The largest box was for a barred owl.

These all have to be built with rough wood surfaces on the inside, or horizontal slits cut into the wood, so that youngsters can climb the wall to leave the box. Otherwise, they can be trapped and die. Nest box specifications by animal species are available. Usually old nest box lining materials should be removed and replaced with new wood pieces before the next breeding season. This reduces the number of fleas and lice overwintering in wait of a new crop of nestlings.

We gather and use rotten birch to line the nests. After three decades of tree tending on our lot, there now are dead and dying trees for all but the largest animal species. So we have stopped erecting small boxes. The natural hole a flicker makes as a nest in the spring may be used by a flying squirrel for overwintering. Next spring, a saw-whet owl may occupy the same hole for its nest.

We continue to maintain the barred owl box until the day they can find a natural hole in a large tree. Nest box plans are available at libraries, bookstores and on line. It makes a great winter project. Youngsters can be enlisted to help build and erect these boxes as a way for them to learn to be caretakers of nature. Bumble bees nested in one of my boxes. They pollinate flowers!

After 30 years, the bottoms have fallen off many of our older, smaller nest boxes. I leave them up for bats. Special designs for communal female bat houses can be found, which allow them to rear their young and adjust brooding temperatures. Bats are the main predator of night-flying insects such as moths, beetles and mosquitoes. A bat can eat 30-50 percent of its body weight in bugs each night. Bats can help protect gardens and farm crops.

Restoring nature's ways helps to build healthy woodlands!