New Hampshire's forests are rebounding from two centuries of clearing for agriculture and from logging. Vigorous second and third-growth forests are beginning to attain the old large diameter trees preferred by the huge, red-crested pileated woodpecker for building cavity nests. Over the past five decades, eastern forests have matured enough to support larger diameter dead and dying old trees. These are colonized by carpenter ants, termites and beetles which are preferred by pileated woodpeckers that have rebounded in nearly every state!

The return of cavity-dwelling, habitat specialists like pileated woodpeckers, sawwhet owls and fishers accompanied the return of habitat only provided by a mature forest. It’s also true that other specialized habitats on the opposite side of the continuum provide species with what they most require. Shrubby agricultural fields or former apple orchards support golden-winged warblers, woodcocks and cottontail rabbits.

Regenerating thickets of hardwood saplings following clearcutting are favored by chestnut-sided warblers, snowshoe hare, lynx and moose. The problem with citing a suite of wildlife as “poster children” to support creating specific habitats is that an equal and opposite suite of habitat specialist species could provide the opposing rationale!

While piliated woodpeckers are now common in the forest, it's unlikely that any habitat specialists will eclipse the sheer numbers of habitat generalists like robins, gray squirrels or white-tailed deer!

As recently as the 1960’s it was unusual to hear that ringing woodpecker call now considered common. Pileated Woodpeckers' return was made possible by old, dying trees.

Paper birch is uniquely adapted to survive at high elevations and northern latitudes, growing as far north as treeline in the Canadian arctic and to the summits of the Applachian mountains, competing successfully against frugal evergreen spruce and fir in the northern boreal forests. At elevations above 2,500 feet, familiar hardwoods give way to birches and conifers. Changes in forest composition are not a direct response to elevation but to decreased air temperature and increased precipitation.

Birches have photosynthetic ability within their bark to supplement scant carbohydrates produced by leaves during the short mountain growing season. With chlorophyll in their bark northern birches are capable of producing sugars in twigs and young stems during warm sunny days of winter long before trees actually leaf-out. They take a head-start on the growing season.

Why does the bark of paper birch so readily peel? It's thought that perhaps peeling bark helps shed lichens in northern locales. In winter white bark plays an important role in deflecting absorption of heat from sunlight that would otherwise subject the dark bark of more southern species to harsh thaw and re-freeze cycles.

Paper birch also thrives after forest fires. Pure birch stands developed at high elevations which burned after turn-of-the-century clear-cutting. Paper Birch exhibits the frugal habits often associated with Yankee character.

Our New Hampshire State Tree - the "Paper Birch" also called "Canoe Birch" is appealing - literally. It's unique white peeling outer layers of bark easily separate into thin sheets like paper.

Strategies like fragrance and color. But not all fragrance smells like a rose. Skunk cabbage, named for its smell, lures in flies and beetles that think they've found something good and rotten. The lovely red trillium, another early bloomer, employs a stinky smell plus a blood-red color for further effect.

Some wildflowers evolve to attract a specific pollinator, and there’s no better example than cardinal flowers and hummingbirds. In August, clusters of iridescent red cardinal flowers bloom along New Hampshire waterways. Many tubular flowers grow on each upright stem.

Hummingbirds are attracted to red, and have evolved to sip nectar from these flowers. They also feed most actively in August, doubling their weight before they take off for their long journey south. It’s no coincidence that cardinal flower blooms in August.

Hummingbirds work a cluster of these neon red blooms in a blur of speed. But, in slow motion, here's what's going on. The hummingbird hovers, tongue extending to reach nectar deep within the flower tube. Inadvertently, its forehead touches another tube that bears pollen. With pollen on forehead, the hummer moves on to sip at a female flower whose pollen receptor is located in just the right place with just the right stickiness. And transfer of pollen from forehead to flower is achieved.

In time, pollinated flower develops seeds and well fed hummingbird departs on migration. But right now, cardinal flowers and hummingbirds can be observed – down by the riverside: A great place to spend some time before summer slips away.

I talked last week about flowers and their pollinating partners, how different plants have developed strategies to lure in certain pollinators.

I can no more imagine hot summer evenings without bats overhead than a summer night sky devoid of all stars….

Now the specter of a regional bat population collapse due to “White Nosed Syndrome” caused by a fungus found in their winter cave hibernacula brings new anxiety to bat watching.

White Nose Syndrome was first detected in New York in 2007 and discovered in the largest known regional winter bat “hibernaculum” at Aeolus Cave, Vermont in 2008. Before WNS, Aeolus had an estimated population as high as 300,000 bats. Since then, numbers plummeted by as much as 90% - a loss of hundreds of thousands of bats. WNS first appeared in New Hampshire in 2009.

Most bats succumb in winter or shortly after emerging from hibernation and before mating in spring. By summer, small groups of males roost in local caves, beneath loose tree bark or on building exteriors. Larger groups of females use hot buildings for summer maternity colonies to raise pups.

Property owners are asked to accommodate bats rather than exclude bats from maternity colony sites in attics, barns or garages. NH Fish and Game is looking for volunteers to complete bat surveys this summer.

You may not realize how important bats are to humans. In New England, bats are the most numerous predators of night flying insects. Bats provide critical ecological services, consuming millions of destructive insect pests including adult moths of defoliating tent caterpillars.

On our Tree Farm, we see fewer bats this summer. It’s becoming a worrisome vigil. We watch one or two flutter over the pasture and sadly ponder what might happen if they too disappear.

The ecological role of bats and what's really at stake with White Nose Syndrome.