Friday, March 20, 2015

Spring Burn With The PHTFD

Bill Collins, Executive Director, Thumb Land Conservancy

Since taking over stewardship in 2011 of the Saint Clair County Road Commission and Pro-Tel Development preserves along the east side of Michigan Road, between Dove Road and the Canadian National Railway, in Port Huron Township, it was clear that control of invasive Glossy Buckthorn is the big management issue out there. Refer back two posts ago to “Michigan Road Preserve Stewardship” for more details about these preserves. Glossy Buckthorn – Rhamnus frangula, recently renamed as Frangula alnus, is native to Eurasia and North Africa. It was introduced to North America about 200 years ago, first as an ornamental hedge plant, and later as a planting for wildlife and other conservation uses. Like so many other shrubs brought to North America for these purposes, including Common Privet, Tartarian Honeysuckle, and Autumn-olive, Glossy Buckthorn became highly invasive, especially in open forests and shrub swamps. It forms very dense shrub thickets that shade-out and displace nearly every other plant species that once grew in the same area.

Glossy Buckthorn on the west edge of the Road Commission preserve.

The best control for Glossy Buckthorn is pulling the smaller plants and cutting the larger, usually combined with herbicide applications. This is very labor-intensive, requiring a lot of people and time to make significant progress against large areas of Glossy Buckthorn such as on the west sides and interior shrub swamps on both Michigan Road preserves. And herbicide has the disadvantage of not always being so selective in which plants it kills. We are aware that some land managers have had tremendous success in controlling Glossy Buckthorn in shrub swamps by burning. This is usually more effective in open wetlands where there is more herbaceous growth and therefore, more fuel for burning. Except during autumn leaf fall, there is not typically a large amount of dry fuel on the ground of mature forests, and therefore, burning is more difficult.

Another aspect of the burning is that, to some extent, the northern plant community on these preserves and across drier sandy soils in the Port Huron area, is probably fire-dependent. Oaks, Paper Birch, blueberry, Wintergreen, Bunchberry, and other species on the upland sand ridges on the preserves all thrive in response to burning. Fire should help to restore some of the natural structure of the vegetation among other benefits. 

We decided to try burning on the west side of the two Michigan Road preserves to see how the buckthorn would be affected in the swamp forest. We considered burning in the shrub swamp portions of the preserves, but we didn’t want to decrease the Tag Alder – Alnus incana cover which appears to be competing with the Glossy Buckthorn, and we don’t want to open these areas to further invasion by Reed – Phragmites australis which dominates the lower wetter areas.

Typical mix of Tag Alder and Glossy Buckthorn down in the shrub swamp.

I had been in contact with Port Huron Township Fire Chief, Craig Miller, since the winter of 2011-2012 about conducting small test burns on the preserves . Craig is an old friend from school and Boy Scouts so it was nice to talk with him again after so many years. But, the spring of 2012 passed without the TLC being granted permission to burn by the Township. The summer drought of 2012 made burning a very hazardous proposition, so any pursuit of burning was dropped for 2012.

In the meantime, with the help of the Michigan Prescribed Fire Council and a few burn consultants, Mike Appel and David Borneman I wrote burn plans for each of the Michigan Road preserves as well as the TLC Dead End Woods Sanctuary and Peltier Beach Ridges Sanctuary. Most of the work for these plans is actually in gathering all the current landowner names that surround the preserves so they can be notified of a burn. I then submitted the plans to the Port Huron Township and Fort Gratiot Township Fire Chiefs for their review. I even thought about showing them my old JFBA - Junior Fire Bug Association membership card from Troop 169 to see if that might help, but decided to hold off.

The burn plans seemed to help because in the spring of 2013, with Chief Miller’s help, the TLC received permission to burn. However, the spring was so wet and cool that burning was not possible before the emergence of forest herbs. Of particular concern is the possible occurrence of Michigan Endangered Painted Trillium – Trillium undulatum, which normally emerges from the ground in mid-May. We considered conducting a burn in the fall of 2013, but again, conditions were generally unsuitable with frequent rains.

Painted Trillium

Finally, thanks again to rather last-minute accommodations by Chief Miller and the generous help of several volunteers on the Port Huron Township Fire Department, we were able to conduct two small burns on April 12 of 2014. Our burn window opened suddenly. Conditions were warm and dry enough only for a few days before turning cold and wet again all the way through May.

To my surprise, when we arrived at the fire department that morning, I was greeted by another old Scouting friend, John Bachman. I hadn’t seen him I guess since he was barely out of high school. He knew who I was, but before I recognized him, he had to give me a jab about being some kind of ecology nut or something. I was probably his instructor for Environmental Science merit badge at summer camp. Then later on our first burn site, Chief Craig Miller came out, the first I’d seen him since our Scouting days. Both Craig and John were in Troop 178 from Port Huron Township. I knew several of the guys in their troop. Their Scoutmaster, Don McColeman, was even a friend in later years. In 1974, after my first summer camp at Silver Trails with my Troop 169 from Fort Gratiot, I stayed a second week with Troop 178. It was a very nice reunion that morning and a reminder of the contribution Scouts make to our emergency services throughout the US, and probably across the world. And it seems Scouts and fire just naturally go together.

Captain John Bachman monitoring the situation.

Typical burn intensity on the Road Commission preserve.

One of the crew sweeping along a control line.

Post-burn on the Road Commission preserve.

Spraying the north edge of the Road Commission preserve after the burn.

Burn line on the Pro-Tel preserve.

Post-burn on part of the Pro-Tel preserve.

The test burns were conducted largely according to the plans submitted to the Township. We adjusted the location of the burn on the Road Commission preserve somewhat because part of the proposed area was too wet. On the Pro-Tel preserve, we burned a slightly larger area than the proposed 100-foot by 100-foot test size, simply for ease of establishing a better south control line with good access. Leaf litter and twigs on the forest floor burned fairly well on both sites, interrupted only by lower saturated soils and lack of fuel in some spots. Almost no material above the ground surface, such as dry branches, burned to any significant degree. The fire crew did a great job sweeping along the control lines to make sure the fire didn’t burn beyond, and we had no trouble at all. Actually, I think we were all hoping for more burn intensity, but the fuel was a bit thin and the soil still mostly damp.

During the summer 2014 preserve monitoring, some decrease in the number and density of small-diameter, less than 0.5-inch, woody vegetation was noted in each burn area. The results will be clearer in 2015 due to delayed resprouting of some stems, but it appears that burning under a forest canopy, combined with hand-pulling and cutting, is likely to be effective in helping to control Glossy Buckthorn in the forested portions of the preserves.