The term “disturbance dependent” is well understood in our circles. We recognize that habitat diversity is essential, and in a healthy forest, disturbance delivers that diversity. Of course, that’s why we advocate for active forest management. But have you ever thought about the natural processes we’re trying to emulate with forest management? Ruffed grouse have been around for some 25,000 years; what forces maintained habitat diversity during the first 99.5% of their existence in our woodlands before saws and skidders? As this issue arrives in mailboxes, habitat managers will be working hard to reinstate one of the most important – fire!
First, some perspective on the past 100 years (call it “The Smokey Bear Era”) that’s been an unprecedented, fire-free blip in ecological history. Studies aimed at charting past fires, whether through scars on tree stumps or ash deposits in soil, show that fires burned quite often across much of eastern North America. Research projects from Ontario to North Carolina show that fires occurred every 5-10 years, with 30-50 years being a long interval for some forest types. So, our forests should have been fire-disturbed multiple times throughout The Smokey Bear Era. The fact that fire was excluded has led to many forest health issues we see today.
It’s important to note that many fires historically were intentionally set by indigenous people. These humans were intimately connected with the land and burned to increase game, manage pests and facilitate forest travel. All things we can get into at RGS & AWS!
While public support for prescribed fire has grown, there’s still skepticism. That’s understandable since the message that forest fires are all bad has been among the most successful marketing campaigns ever undertaken. Nonetheless, today’s science and leading wildlife biologists see prescribed fire as a real difference-maker. I share these thoughts hoping to clarify why fire is essential and set the stage for more detailed articles in future Covers issues. The following are a few of the most frequent comments I’ve heard over two decades in forest habitat and fire management.
Comment #1: The prescribed fires I see only burn leaves on the forest floor.
While some prescribed fires appear only to burn leaf litter, they’re doing important work. Low-intensity fires are designed to kill small saplings and invasive plants and reduce dead leaves and brush accumulated where fire was unnaturally kept out for a century or more. Fire restoration is a process, not a single event. In many cases, it’s like peeling an onion with fire applied judiciously over successive years, removing one layer at a time.
Comment #2: Prescribed fires don’t open the tree canopy and create early successional habitat.
Fire is important for early successional habitat creation in several ways. It can be a preliminary treatment that sets the stage for timber harvest. For example, low-intensity fire can foster certain seedlings like oak and pine. With young trees established and ready to grow, mature trees can be harvested, making way for a young forest to grow. In this way, fire is used in conjunction with timber harvest.
Fire can also create young forest directly by killing overstory trees. This is especially relevant where access or tree quality can’t support commercial timber harvesting. Here, habitat managers can prescribe a hotter fire that kills some trees and makes significant gaps in the forest canopy. If not for fire, there would be few or no other options to intersperse young forest habitat in remote areas.
We certainly can’t forget about shrublands. These early successional habitats are vital, and fire is a key management tool. A great example is the scrub oak (aka bear oak) habitat found from the upper Great Lakes, through the Mid-Atlantic region, to New England. Scrub oak habitats are a fraction of their historic distribution due to, you guessed it, fire exclusion. Frequent fires every 5-10 years are necessary to keep scrub oak habitats healthy and in good supply, and scrub oak restoration is a stated goal for many of our agency partners.
Comment #3: Won’t fire negatively impact nesting?
Having spent many years implementing prescribed burns and researching their impacts, this is a question I’ve heard a lot. The effects of prescribed burning aren’t what you might expect. A few nests might be disrupted by fire, but those hens often nest again, and some nests may not be harmed at all by low-intensity fires. Most importantly, burns occur on a relatively small percentage of the landscape (usually less than 10%) in any given year. As such, the long-term positive outcomes outweigh any direct, negative effects.
Melting snow, March winds and spring sunshine signal prime time for prescribed burning. It’s crucial for RGS & AWS to support these efforts. Our Forest Conservation Directors will provide detailed project information in the coming months. Keep an eye out for more information and in the meantime, lend support to your local habitat managers looking to harness fire’s energy for habitat good.