Monday, March 26, 2012

Natural History: The Ecology of Adirondack Fires

There are several natural disasters that can alter the ecological make-up of an area. Wide spread tree disease, severe winds and intense ice storms can all seriously damage or destroy the dominant members of a forest community. However, the most catastrophic force of nature is fire, as a major blaze can significantly impact more than just the composition of trees that cover a given location.

Unlike other natural calamities, fire can wipe out most of the plants that root in an area. In an ice storm, or a major wind event, it is primarily the older and taller trees that are subject to the greatest devastation. Seedlings, saplings, the various shrubs that form the understory and the array of herbaceous plants that grow on the forest floor often benefit from the increase in sunlight that result when the canopy has been drastically thinned or eliminated. During an intense fire, however, the entire plant community can be obliterated.

As would be expected, the wildlife that resides in an area ravaged by fire would also experience significant change. Some larger animals, like deer, coyotes and bobcats may continue to travel through a scorched setting en route to places not impacted by fire. Many smaller creatures that formerly inhabited that site may not be able to reestablish a population in the affected area. Creatures like salamanders and shrews both require a damp carpet of dead leaves and needles under the shade of a fairly thick canopy in which to live. An open field or a large, brushy clearing is subject to unfavorable thermal conditions during sunny days in summer, and results in a microclimate that is too dry for these ground dwellers. Warblers, vireos and squirrels find a lattice of branches and limbs essential for placing their nest and obtaining food.

While a severe fire can destroy the current ecological state of an area, there are numerous forms of life that are quick to colonize any site in which the competition has been eliminated. The aspens, with their tiny, cottony seeds that can travel for miles on strong breezes, can reseed a burned over site in only a few years. Because the aspens are fast growing, it doesn’t take long before a young forest may sprout on that site.

Likewise, it takes less than a decade for the seeds of white birch, white pine and Scotch pine to find their way to these open places and sprout in the abundant sunlight. Raspberry, blackberry, and several species of cherry are also quick to sprout and root in places in which there is little competition for light, despite the fact that the soil may not contain many nutrients.

In places where a hot fire incinerated all the organic matter in the soil, a plant community of ferns, grass and low shrubs will eventually develop. Thickets of waist high bracken fern along with dense patches of blueberries and huckleberries, and scattered clumps of meadowsweet are able to grow where only sand and ash exist.

Each of these unique settings harbors its own wildlife community and is able to support numerous transients that visit to feast on the various berries and seeds that several of these plants yield at certain times of the summer season. The importance of a diverse food source for wildlife is especially helpful in maintaining the health of an animal population.

It doesn’t take long for life to return following a fire, and then for the area to change again. The shrubs and trees that grow in open settings tend to be fast growing and short-lived. After they have matured, their own seedlings are unable to sprout in the immediate area, as the shade the parent casts is sufficient to prevent their offspring from growing properly. The pioneer stage of succession that forms after a fire tends to transition into more advanced plant communities within only four or five decades.

It has been almost a century since the Adirondacks experienced an intense, widespread forest fire. While there have been numerous, localized blazes over the years, these fires were confined by the rapid response of experienced forest rangers and hard-working volunteers from fire departments across the Park.

While fire is capable of destroying a stand of timber, especially softwoods, faster than any modern logging operation, and do more damage, the ecological communities that form afterwards have their role in nature’s intricate web of life. Despite the ugly scars on the landscape, nature is far quicker to recover than most people could imagine. No one wants to see this kind of natural disaster, but the excessively dry conditions that appear to be developing this spring could create one of the worst fire seasons in recent memory. Forest fire prevention should be a primary focus of everyone who ventures into the woods, as there is always the possibility of the loss of human life with a fire.

Photo: The 1965 Pottersville Fire (courtesy nysforestrangers.com).


Tom Kalinowski

Tom Kalinowski is an avid outdoor enthusiast who taught field biology and ecology at Saranac Lake High School for 33 years. He has written numerous articles on natural history for Adirondack Life, The Conservationist, and Adirondack Explorer magazines and a weekly nature column for the Lake Placid News. In addition, Tom’s books, An Adirondack Almanac, and his most recent work entitled Adirondack Nature Notes, focuses on various events that occur among the region’s flora and fauna during very specific times of the calendar year. He also spends time photographing wildlife. Tom’s pictures have appeared in various publications across the New York State.




6 Responses

  1. Paul says:

    Tom, I was on the Blue Mt. Road near Bay Pond Preserve (“Rockefeller’s”) this past weekend. They have these areas there where there must have been fires. Meadows with remnants of old stumps. It seems like forest succession there is not really happening like it might normally occur? I wonder if these areas had the soil very badly burned at some point. I know that area had large fires after the turn of the last century. The meadows have some grasses and mosses and there are some pines here and there but very little vegetation. Strange to see in that area. You can see it clearly from Google maps. Do you know anything about the history of these areas?

  2. Tom Kalinowski says:

    Hi Paul: There are several very large tracts of land in that area that were severely burned by fire about a century ago. I believe that many of those areas are covered by blueberries, grasses and bracken ferns. (The ferns are not currently up, but will be visible in another month or so.) The very slow rate of succession in this area is the result of the infertile soil there. That area is quite rich in history and would take an entire article to touch on the more significant events involving that tract of land.

  3. Dave Gibson says:

    Tom,

    I believe the last intense Bay Pond area fire was in the 1930s, so not too many generations ago. The landscape and ecology there offer tremendous diversity as a result of those catastrophic fires.

  4. Paul says:

    Dave. I agree. When you go through those areas in the late evening (at least the ones you can see from the road since the area is very heavily posted and patrolled) it is almost like a “lunar” landscape of sorts. I have seen some similar areas but nothing on that scale. Like I said from Google maps you can see that you are only looking at a very small part of a very large area that has been affected there.

    Tom on the bracken ferns I think I read in one of Barbara McMartin’s books that these ferns also can greatly decrease the ability for the seedlings to take root and it basically halts forest succession. You see this in many areas on Forest Preserve land. I have seen this on private parcels as well.
    3/27/2012 10:41 AM

  5. Tom Kalinowski says:

    Thanks Dave for the correct time frame. I definitely agree with you that the area around Bay Pond does have tremendous ecological diversity. There are very few settings in the Park that can match that parcel of property.
    Paul- Bracken fern does indeed slow the rate of succession with the dense shade that it produces, however, nothing lasts forever and I have seen places covered in Bracken fern eventually transition into a forest, but it does take several decades to occur.

  6. Paul says:

    “Several decades” – Just a blink!

    Thanks, Tom.