Like many articles in The Chronicle, this one begins at a public meeting. But unlike any others, it ends in a partially burned woods at Argo Nature Area, where a crew clad in yellow fire-retardant suits kicked up puffs of smoke as they strode through the ashes of their work.
On the path from one to the other, we learned about sling psychrometers, drip torches, council rakes and what kind of leaves burn best. Our guides were the staff and volunteers of Ann Arbor’s Natural Area Preservation program, who will be wrapping up the spring burn season later this month.
We first got an overview of the city’s controlled burn program from NAP’s manager, Dave Borneman, who made a presentation about it at the February meeting of the Ann Arbor park advisory commission. He described the ecological rationale behind a burn, citing the benefits it brings by controlling invasive species and rejuvenating the land.
As it turns out, Borneman was also the “burn boss” when we tagged along on a burn last Friday – the first one done by NAP in Argo’s lowland area.
But the day for the crew began at their offices in the Leslie Science & Nature Center building, on Traver Road – so that’s where we’ll start, too.
Will Today Be a Burn Day?
Because of consistently dry weather – a trend that’s been disrupted this week – this spring has been a remarkably good one for controlled burns. The last week of March and the early days of April leading into Easter weekend were shaping up to continue the streak – on April 1, dozens of spectators showed up for the popular annual burn at the Buhr Park Children’s Wet Meadow, which went well.
By Friday, though, as the NAP staff gathered for their morning meeting, the National Weather Service had issued a “red flag warning” for southeast Michigan – an indicator of “critical fire weather conditions.” And because dry, hot weather made the spread of fire a risk, the state’s Dept. of Natural Resources and Environment stopped issuing burn permits.
NAP has a blanket permit for its controlled burns from Ann Arbor’s fire marshal, covering the spring and fall seasons. Even so, the fire marshal gets to make the call on any given day – checking in with the fire marshal is part of NAP’s protocol before doing a controlled burn. On Friday, there was a period of uncertainty, as the burn crew waited to hear back about whether they’d be allowed to proceed.
Uncertainty is part of the drill. Even if the weather forecast looks solid, conditions might change overnight. So the burn/no burn decision is made in the morning, following a series of checkpoints made by staff.
On Friday, Tina Roselle walked The Chronicle through some of those checks from NAP’s second floor offices in Dr. Leslie’s old homestead, where the Leslie Science & Nature Center is also located.
Roselle is coordinator of the city’s Adopt-a-Park program, but during burn season she often spends the morning doing prep work for the crew. Next to her desk is a large plastic tub, which she is filling with supplies:
- Extra water bottles.
- Medical forms and sign-in sheets for volunteers.
- A plastic bag crammed with Oskri bars – they’re good because they’re vegan, organic, gluten-free and edible by people who have food allergies, Roselle says. Other snacks are in the tub as well, including crackers and peanut butter creme cookies. (Roselle also walks across the office and pulls back a curtain to reveal shelves full of additional snacks – more fuel for the volunteers and staff.)
- A red cloth pouch with several tools for checking the weather, including a Kestrel 3000 wind meter, a compass to identify wind direction, and a sling psychrometer to measure humidity on site.
Roselle also checks a range of weather conditions so that the crew can know what to expect out in the field. She calls a number at the Ann Arbor municipal airport – 734-668-7173 – that gives a recording of wind speed and direction, temperature and other conditions specific to the city. She prints out a report from the National Weather Service website for the Ann Arbor area – the site includes hourly forecasts for humidity, precipitation, wind gusts and other measures.
Wind speed and direction are important, as those indicate how the fire might burn, and how smoke from the burn might affect surrounding areas. Those conditions factor into the selection of the burn site on any given day.
Humidity is another factor, because it generally predicts the dryness of the oak leaf “litter” or grasses, which fuel the burns. Since humidity is typically lowest around midday, most of the burns begin at noon.
Part of Roselle’s job can’t be done until the burn crew emerges from their morning meeting, where they discuss which sites to tackle out of a master list that’s been compiled for the season. Depending on weather conditions, the number of people available and the size of the burn sites, up to six locations might be handled in a day. Typically, though, the crew usually tackles one or two larger sites.
On Friday, there was just one burn – at Argo. So Roselle pulls a “burn prescription” for that location. These extremely detailed reports are prepared for each potential site in advance by NAP staff, with some information to be completed on the morning of the burn. Essentially it’s a how-to sheet, listing the location of the site, how to get there, who owns it, where the nearest water source is, and who needs to be notified about the burn – including a list of contact information. It also includes burn objectives – in the case of Argo Nature Area, the main goal is to kill garlic mustard, an invasive plant species.
There are also details about smoke management, one of the more important elements of a burn in terms of potential impact on the surrounding community. A smoke management plan might look something like this, taken from a sample burn prescription for Cedar Bend Park:
1) Conduct burn when atmospheric conditions allow for maximum lifting, mixing and transportation.
2) Create burn breaks around dead snags, chimney trees, stumps, logs brush piles to prevent burning.
3) Attempt to have the burn and mop-up completed prior to rush hour traffic.
4) Make sure nothing is left smoldering when we leave the site.
5) Schedule burn during weekdays when fewer people on-site or in nearby homes.
After getting the good-to-go signal for the day, Roselle makes calls to the contacts specified in the burn prescription. She also sends out a mass email to volunteers, giving details about when and where the day’s burn will occur. Media outlets get an email too, and word goes out over NAP’s Twitter and Facebook accounts. [To sign up for alerts about controlled burns or other NAP activities, email email@example.com.]
It takes at least an hour – usually more – to make all the contacts, Roselle says.
Pre-Burn Prep Work
Meanwhile, other NAP workers are getting together equipment and supplies for the day. On Friday, we found Steven Parrish in a basement workshop, sharpening tools. He nicked his finger on a pulaski, a combination axe and mattock. “I did a good job sharpening that,” he deadpans, sucking on the blood.
Shovels, picks, council rakes, chainsaws, two-way radios – all manner of tools and equipment are stacked in this basement storage area, where lockers for the crew are also located. The lockers are used to store each person’s burn crew suit, issued for the season – either a one-piece jumpsuit or pants and a jacket, made of heavy yellow fire-retardant material. In the same way that the brand name Kleenex has taken on a generic meaning, the suits are called Nomex – a brand name that’s commonly used to refer to any fire-retardant suit. (And unless they get particularly nasty, the suits are washed only at the end of the burn season.) Each crew member also has a yellow helmet with plexiglass visor – on the front, their name is written in large letters on yellow duct tape.
Part of the prep work includes making sure all the equipment is ready, Parrish says. In addition to sharpening tools, he’s already repaired the metal frame on a backpack that holds a metal water tank.
Most of the other half-dozen workers are elsewhere on the grounds. Some have gone to the nearby Leslie Park Golf Course to fill up the tank on the water truck. Others are loading a large red trailer – among its contents are several signs that will later be placed on roads around the area of a burn, to alert residents and drivers who might spot the smoke. The trailer also holds orange road cones, leaf blowers used to create a break around the perimeter of the burn, blue plastic tubs filled with fire-retardant suits in an assortment of sizes for volunteers, and a hodge-podge of tools.
Up the hill, Robb Johnston has driven a pickup truck to a storage shed and is hoisting five-gallon red and blue metal canisters of fuel into the truckbed. The crew uses fuel for its chainsaws and for pumps on the water trucks.
He’s also loaded 11 drip torches – smaller canisters with long nozzles that are carried by the burn crew and used to light the fires. The drip torches are filled with a cocktail of kerosene and gasoline in a four-to-one ratio – instructions for the mix are scrawled in marker on the inside of the shed. Johnston explains that kerosene makes for a sustained burn, mellowing out the more explosive gasoline. Explosiveness on a controlled burn is not good.
At the Burn Site: Getting Ready
By 11:30 a.m., a pickup truck with NAP’s distinctive red trailer is already parked in the lot near the entrance to the nature area. Laura Mueller has opened the trailer door and unloaded the blue plastic tubs with gear for volunteers, along with several of the water-tank backpacks and a tub of snacks.
In part because of the Good Friday holiday, there’s a fair amount of activity – kids playing across the road in Longshore Park, joggers, dog-walkers, fishermen, people driving in and unloading their canoes and kayaks. A couple of geese waddle along the shore, honking. Across the Huron River, an Amtrak train rolls by.
A sign is already posted at the head of the trail where you enter the woods, stating that the nature area is closed. Throughout the afternoon, this is routinely ignored – and that’s pretty typical, according to the burn crew. When working in the urban parks, it’s common for people to go through a burn site, and there’s not much the staff can do about it.
Volunteers begin to arrive. The first is Gracie Holliday, an undergraduate at the University of Michigan. She’s been a NAP volunteer for other projects, but aside from the training that all volunteers must complete, this is her first burn. A petite woman, she roots through the tub marked “S” to find some gear that fits – sort of.
By noon, about a half-dozen other volunteers have arrived, coming by bike, motorcycle and car. They also gear up, though at least one man – Jim Hope, who’s also a firefighter – wears his own suit. In general, volunteers are asked to wear their own leather boots, but are provided everything else, including well-worn leather gloves and two-way radios that are clipped to the front of their jackets. They pass around a clipboard to sign in. Some have brought their own lunch, but others grab a snack from the tub provided by NAP. Amanda Nimke passes out clementines.
Dave Borneman shows up – he’s parked the burn trailer for his private business in a parking lot down the road. He’s the “burn boss” for the day, and consults with Lara Treemore-Spears, a NAP technician who’s also supervising the site. Other staff prepare the drip torches, fill water tanks, and help volunteers get into their gear. A couple of kayakers ask Mueller to take a photo of them before launching their craft into Argo Pond – she obliges.
About a dozen people – staff and volunteers – are in their full gear when Borneman asks everyone to huddle up. They form a circle, and make introductions. Borneman passes out maps of the area, and talks about conditions for the day – it’s dry, he says, with high temperatures and wind creating a greater chance for fires to start and spread, “which is why we’re not in a cattail field.” He clarifies that there’s not a burn ban in effect, and that the fire marshal has given the go-ahead for their work. Even so, Borneman says he wouldn’t be surprised to see a fire truck cruise by during the afternoon. “We’re going to avoid every opportunity for them to shut us down,” he says.
Borneman notes that two people from NAP’s staff will be driving around the neighborhood, monitoring smoke. Smoke monitoring will be especially important today, he says: Because of the holiday, more people will likely be at home and outside, and because the weather’s nice, homes in the area are more likely to have their windows open. He notes that the gray overcast sky works to their advantage, masking the visible signs of smoke so that residents won’t get concerned.
Borneman tells volunteers that they’ve never done a controlled burn in the lowland area of the Argo Nature Area, and he included a bit of a pep talk: “It’s going to be a great burn day!” He cautioned them to try to burn around the patches of trout lilies, bloodroot and other wildflowers they find. This is done by dousing the flowers with water just prior to the burn. It’s an effective strategy.
In wrapping up, Borneman urges the volunteers to make sure they drank plenty of water – everyone needed to carry a water bottle. When they return to the base to refill the water tanks on their backpacks, he said, be sure to grab something to eat as well. “Expect to be really hot and tired and sweaty,” he said.
They then quickly divy up tasks. Four volunteers are chosen to ignite the fires with drip torches – this seemed to be a coveted job, and volunteers were picked who hadn’t done any igniting recently, or in the case of Holliday, ever.
Parrish gives an on-site weather report, which would be updated every hour: 72 degrees, with relative humidity at 45% and wind from the south. Borneman does a radio check, making each person could receive and transmit clearly.
And with that, they flip down their visors and get to work.