Invasive Species Management and Climate Change

As I wind down the season this last week of September, my time working on the stewardship crew these past months sure seems to have flown by. Although this is not my first season in a position on a field crew, I’ve still learned a ton of new and insightful information relating to land management, ecosystem restoration, and Michigan’s natural features. The majority of the work I performed was helping to control invasive species populations throughout Oakland Township’s parks. While in our day to day tasks, it can be hard to look at the big picture of invasive species management and how to assess long-term goals. Though reflecting on our work and talking with the director of Oakland County’s Cooperative Invasive Species Management Area, I hope to do just that.

What Makes a Plant “Invasive”?

Working throughout the season, I have seen firsthand the devastation that certain plants have caused in our parks. How is it that we label these havoc-wreaking species as “invasive”, and what makes them so detrimental? An invasive species can be defined as a non-native species (plant, animal, disease, etc.) with the ability to “invade” or “take over” an ecosystem in a way cause s a negative impact on the environment, human health, or the economy. In most cases, an invasive species’ introduction into an area is brought on by human activity, such as the purposeful or accidental transportation of the species from one part of the world to another. In their native ranges, these species have evolved to serve an important role in their ecosystems, and are kept in check by natural competitors. However, the same species can have catastrophic effects when transplanted to new environments that haven’t had thousands to millions of years to adapt to its presence. Because of this, they are able to outcompete native species and drive an overall biodiversity loss. For example, Oriental bittersweet is an ornamental plant brought over from Eastern Asia that has the capability to spread rampantly throughout our forests. Its vining growth habit leads it to grow around trees or shrubs and eventually strangle them to death, or cover a massive amount of area on the forest floor. Oriental bittersweet and other invasive plants disrupt an area’s native food web which limits resources critical for native birds, bees, butterflies, and other animals. These effects also work to destroy habitat for native wildlife.

A Changing Climate Creates New Challenges

Our earth is experiencing changes at an abnormally high rate as time progresses. Climate change news is always prevalent, but has had significant media attention especially recently as the Intergovernmental Panel on Climate Change published its report highlighting the devastating consequences of our changing planet. I was curious to see how exactly increasing global temperatures and more extreme weather events would affect the prevalence of invasive plant species. In short, I found that longer summer growth seasons will allow for more vegetative growth of invaders, and overall warming will shift individual species ranges northward over generations.

I noticed firsthand this spring that there was the absence of water in a lot of areas that should have been seasonally wet, such as vernal pools and the Paint Creek Heritage Area – Wet Prairie. Although anecdotal, this observation may tie into the fact that we had less snowfall this past winter due to drier and warmer than average conditions. Fluctuations in temperature and precipitation are commonplace year to year, but climate change will make them more common and extreme. So, what does this mean for invasive species? Based on what I’ve learned about wet prairies this year, this habitat type relies on periodic wetness to help keep its native species dominant and drown out unwelcomed guests. However, certain invasive plants like purple loosestrife and narrow-leaf cattail may not be bothered, and in some cases may even thrive.

How the Oakland County CISMA is Helping

Since management of invasive species requires cooperation on a local scale, organizations known as Cooperative Invasive Species Management Areas (CISMAs) are often established with the goal of uniting relevant agencies in their efforts to control unwanted species. I was interested in learning more about what kinds of problems climate change introduces for managing invasive species in my local area, so I got in touch with Erica Clites, Director of the Oakland County CISMA. I asked her questions regarding the nature of her work and what the CISMA is doing to prepare for changing climate variables.

What is the role of the Oakland County CISMA in combating invasive species?

The Oakland County CISMA mainly acts as the main information base regarding invasive species in the area. Expertise about species identification and management are offered to both partner organizations and the public. In addition to education, the CISMA is also involved in direct surveying and management of invasive species. Their efforts are often concerned with long-term management, which comes in the form of partnerships with organizations like the Oakland County road commission. Working with the road commission allows them to help manage the spread of invaders like Phragmites australis, a persistent weed that often grows in roadside ditches.

Phragmites australis, an invasive reed that the stewardship crew is well acquainted with, often gets established in the disturbed areas along the edges of roads

What does a changing climate mean for invasive species management in Oakland County?

I asked Erica about how she anticipates climate change will affect her work with the CISMA. Managing invasives is just as much about working in the present as it is looking towards the future. By being aware of the general trend of warmer global temperatures and increased intensity of weather events, Erica can anticipate how certain species will act and which ones to watch out for.

With higher average winter temperatures, more species will be able to live in Michigan than previously. Until recently, certain invasives have been prevented from becoming established here due to their inability to survive our cold winters. Water lettuce and water hyacinth are two non-native aquatic plants that fall under this category. Both species are legal for sale in the water garden trade, with the pretense that they should not be released into the environment. Unfortunately, these plants do eventually end up outside of their intended area, as is often the case with ornamental species. With the threat of warmer winters, water lettuce and water hyacinth have the potential to become invasive if left unchecked. The Oakland County CISMA is aware of the threat of these plants and other potential invasives and works towards removing what they can find as a preventative measure.

Temperature changes often shift the ranges of species over time, and invasive plants are no exception. According to Erica, certain species that are known to be established in the southern US are at risk of moving northward in response to increasing global temperatures. The CISMA remains vigilant and watches for certain species that are predicted to move northward in the future. The Michigan Invasive Species Watchlist is a great resource for those wanting to know which species may be moving into your neighborhood. Species that are expected to move up to Michigan from southward latitudes can be found on this list.

Climate change will create more variable conditions in weather patterns and increase stressors such as drought and extreme heat. I had initially thought that these changes would somewhat even the score since they affect both native and nonnative plant species. However, I was disappointed to learn that invasive species are often more flexible and better equipped to handle these changes than native plants are. Invasive plants are able to successfully populate an area because of their ability to tolerate a wider range of conditions, and this includes weather and climate. Think about an open field that has been turned into a neighborhood. Most species will not be able to tolerate such a dramatic change in their environment, but tenacious plants like dandelions will still pop up through cracks in the pavement.

How You Can Help

My goal in writing this blog post was not to instill you with a feeling of impending doom, but to ignite your motivation to help deal with the threat of invasive species. Fortunately, there are plenty of ways to help for those interested. The Oakland County CISMA’s website has plenty of resources available for identification and management of several of the most common and pervasive species in the county. Their YouTube channel and Facebook page have a lot of useful information as well.

I asked Erica what she would recommend for those wanting to be part of the invasive species mitigation solution, and she recommended a number of options:

If you want to maintain Michigan’s beautiful biodiversity, keep invaders away!

Unique Wetland Communities Along the Paint Creek Trail

The wet prairie showing its ability to retain water after a rainy week

What Makes a Wet Prairie?

A few months ago, you may have seen my blog post detailing the controlled burns that took place in some of our parks. While writing that post, I ended up researching how fire would affect certain habitat types that we burned and became interested in what makes those areas so unique. One such habitat is the Paint Creek Heritage Area – Wet Prairie that was partially burned along the Paint Creek Trail just north of Silverbell Road. If you visit, we would like you to view the wet prairie from the trail to prevent trampling sensitive plants. Because of this, it may be difficult to see what makes this area special at first glance. However, our recent work in this area has afforded me the opportunity to share some of the unique aspects that result from the conditions presented by wet prairie.

An aerial view reveals the original path of Paint Creek that passes through the Paint Creek Heritage Area – Wet Prairie, highlighted in light blue. The wet prairie sits in the floodplain of this former creek. The current Paint Creek is highlighted in dark blue.

When I first visited the wet prairie this spring, I noticed that it wasn’t exactly as wet as advertised. However, revisiting the site after some significant rainfall revealed an increase in standing water, and the area started to live up to its name a little more. I soon discovered that wet prairies occur in areas with poor drainage, leading to periodic fluctuations in water levels that many of its plant species depend on. While helping with the prescribed burns in a few sections along the Paint Creek trail this spring, I learned that water isn’t the only element that plays a role in this ecosystem. Like other prairie habitat types, fire is more than welcome here. The burn we administered this spring will help recycle nutrients and control competing invasive species.

Stewardship Work in The Wet Prairie

Outside of the area that was burned this spring, we have been incorporating mechanical methods to keep invading species at bay and maintain the unique features that are present. Many understory plants associated with a more open oak canopy can be found in the wooded areas of the wet prairie. Unfortunately, certain fast-growing tree species like red maple have become more prevalent made the area much more shaded. One way we have been attempting to increase the growth of new young oak trees is through selective tree girdling of these shade-tolerant species. To girdle a tree we strip a complete ring of bark around an unwanted tree and apply herbicide to the exposed inner sapwood. The result will be a dead snag, allowing more light to the woodland floor and leaving more room for oak species in the canopy and savanna plants in the understory.

Parker girdles a red maple tree by removing a strip of bark all the way around the trunk. Photo by Ben VanderWeide.

In addition to tree girdling, the other stewardship crew members and I have been working to remove other unwanted, invasive species through hand-pulling, mainly targeting garlic mustard, dame’s rocket, spotted knapweed and white sweet clover.

Natural Features Galore

Surveying for various invasive species involves spending a lot of time looking at what other plants are populating the area. Through this process, I discovered the many unique native plants that resided in the wet prairie. The presence of both sunny and shaded areas with wet and dry characteristics create a marvelous diversity of herbaceous plants. Many species contribute to a wide spectrum of flowers depending on the time of year. Such species include blue-eyed grass, butterfly milkweed, hoary puccoon, shrubby cinquefoil, Michigan lily and Culver’s root to name a few. Seeing this beautiful diversity helps drive home the purpose behind our stewardship work in these areas.

Of course, the many unique wildflowers of this habitat attract many pollinators as well. The stewardship crew happened to spot several species of butterflies including viceroys, monarchs, and great spangled fritillaries. We’ve also spotted many birds, notably a pair of great crested flycatchers nesting in a dead snag. Unfortunately, these birds were too quick for our cameras. I also happened to stumble upon a turkey that was nesting right off of the Paint Creek Trail. It may have seen me coming, but I certainly did not see it until I was inches away from its nest.

A nest of turkey eggs on the Paint Creek Trail berm

Stewardship Work in the Fen

The wet prairie isn’t the only unique habitat that can be seen from the Paint Creek Trail. Just a few miles north on the trail between Gunn Road and Adams Road, you may be able to see another interesting area that we have been working to protect: the Paint Creek Heritage Area – Fen. While we didn’t administer a prescribed burn here this spring, my interest and research into unique habitat types lead me to discover a lot of similarities between the wet prairie and the fen. A fen is also a special wetland characterized by soils composed largely of decayed plant material, and is unique in that it is fed by carbonate and calcium-rich groundwater groundwater. Because of these conditions, fens boast a high diversity of plant species including tamarack, poison sumac, and a variety of fen-specialist sedges and wildflowers.

A section of the Paint Creek Heritage Area – Fen

Our work in the fen has mainly consisted of controlling the densely growing non-native narrow-leaf cattail population that has spread and threatened native biodiversity. We control cattail using what we call the “glove of death,” which involves wiping the stem of each cattail with a glove sprayed with an aquatic herbicide. While very selective, I found this process to be one of the more difficult and meticulous invasive control methods we have experienced as it requires us to move carefully through the cattails to avoid touching herbicide-covered plants. Fortunately, we recently experimented with another treatment option that could potentially expedite the process of cattail control in denser areas. This method involves wiping larger areas of cattails with an herbicide-coated towel. Since the cattails are taller than most of the other plants, this treatment is selective.

Many of Michigan’s endangered insect species require these habitat types to survive. The Poweshiek skipperling, Hine’s emerald dragonfly and Mitchell’s satyr butterfly all rely on fens and spring-fed wetland habitat. While not all of these species have necessarily been spotted in Oakland County, the preservation of this habitat type is important wherever possible. Working in these areas is an interesting opportunity to be able to see how our efforts directly impact the land we work in. Some of these effects may take years before there is a greater noticeable change, but others are directly visible from one year to the next. For example, it was interesting to see how many fewer cattails there were in the fen this year after spending time treating them last year. It is in an honor to be taking part in the process of maintaining these unique Michigan wetlands.

If you’re interested in learning more about wet prairies and fens, the Michigan Natural Features Inventory’s website provides plenty of information on these habitat types and which plants and animals you can expect to see there:

Prescribed Burns for Healthy Habitat

Post written by Parker Maynard, Land Stewardship Technician. Post updated June 7 – we accidentally posted a version that wasn’t quite finished last Friday!

Volunteers and natural areas stewardship staff ignite the fields at Bear Creek Nature Park (Photo by Cam Mannino)

I can’t think of a more interesting and exciting way to start the stewardship season than by learning how to light up controlled fires to maintain the beauty of Oakland Township parks. Throughout late April and early May, the other Stewardship Crew members and I were involved in a unique hands-on training experience by participating in several prescribed burns. With the help of volunteers and contractors, areas within several parks underwent changes that will maintain and improve habitat and help native species thrive. As someone who has long been interested in the process of prescribed burns but has never had the chance to participate in one, I can easily say this was one of the most memorable stewardship activities I’ve participated in.

Learning Before Burning

Before I jumped into the action, I was able to learn about the purpose of such an intense process, as well as how to safely utilize and control fires. Through this training, I learned that fire is a regular and beneficial part of the natural cycle of many landscapes, from keeping open prairies free of woody and invasive species to maintaining fire-resistant oak forests. Although it seemed surprising, I learned that fire had historically found its way into these areas again and again, through Native Americans intentionally burning land or lightning striking the ground. In recent history, wildfires have been suppressed, making these habitat types more of a rarity. Fortunately, Oakland Township is working to help preserve what remaining prairie and open oak forests are present in our parks by administering these burns.

Comparison of a burned and unburned field at Bear Creek (Photo by Cam Mannino)

After learning the basics, I was able to observe a prescribed burn in person at Watershed Ridge Park with the rest of the Stewardship Crew. When we arrived at the park, we introduced ourselves the contractors that were going to be conducting the burn, who were busy prepping the site. The site preparation process involved creating a nonflammable boundary around the burn area called a “burn break”. Leaves and other flammable materials were cleared to form a portion of this boundary, but an existing wetland and farm field were also utilized as natural burn breaks since they weren’t likely to carry fire. After all preparations were complete, the burn crew gathered and was briefed on the plan We reviewed a map of the burn area, discussed wind direction and expected weather, talked about noteworthy topography, and went through the ignition and containment plan.

Into the Fire

After more observation and hands-on training, I was excited to be able to participate in a burn myself at Bear Creek Nature Park. This time, the burn would be conducted with a few volunteers, so my role was more integral to the process. Before we began, everybody suited up in proper personal protective equipment (PPE), which included a fire-resistant shirt, pants, gloves and a hardhat. Since I had never actively walked through a burning fire, I was wary as to how “fireproof” these clothes really were. However, I eventually felt safer after the fire began and I was walking in and out of burned areas with ease. We first ignited a slow backing fire by lighting the area against the prevailing wind direction with drip torches. These tools are handheld tanks with a wick to ignite the fuel mixture as it drips onto the ground. I like to think of it as a reverse watering can that pours fire instead of water. After I had gotten some practice with a drip torch, I began feeling more “in control” of the burn.

Lighting an area on fire is one thing, but it is just as important to make sure that the fire is put out afterwards. When we completed our burn, the crew spent a while putting out any actively smoking logs and other materials with backpack water sprayers.

Results of the Burn

So, what are the results of such an intense process? It is difficult to predict exactly how a landscape will react to a fire, but several changes will surely take place. The burning process helps to break down and get rid of dead organic matter and recycle nutrients back into the soil. When a burn takes place in the spring, many perennial plants are in a dormant stage and will be minimally impacted by the fire. Other plants may utilize this newly barren landscape as a chance to grow without as much competition. Plants that are adapted to these cyclical fires will be right at home in this newly created habitat as they are more accustomed to fire, whereas many invading species are not. In some cases, seeds may be spread manually in order to encourage specific species to thrive. The Stewardship Crew spent some time hand-spreading seeds and Natural Areas Stewardship Manager Ben VanderWeide utilized a tractor to spread seeds in areas that had been previously burned at Bear Creek.

Burned area at Charles Ilsley Park with fresh new growth a few weeks after the controlled burn

About a week after our burn at Charles Ilsley Park, I was surprised to see how green the burned fields had become in such a short time. I am especially interested to see how the wet prairie along the Paint Creek Trail will react to the recent burn that took place there, as it hosts many unique fire-tolerant plant species.

A robin looking for food after a burn (Photo by Cam Mannino)

Before participating in these prescribed fires, I was very curious as to how animals would react to the process. During a few of the burns, I observed turkeys, songbirds, and snakes fleeing from the burn area. It was clear that just as plants had evolved to withstand wildfires, many of these critters have as well. Even insects could simply burrow into the ground to evade the danger of fire. I realized that this emigration was only a short-term effect as shortly after the burn was complete, I began to see birds and even a Blanding’s Turtle return to area. I knew that the preservation of uncommon plant communities through burning will in turn help attract rare insects, birds, and other fauna to the area in time.

A Blanding’s Turtle returning to a burned field at Charles Ilsley Park

If you are interested in volunteering to participate in a future prescribed burn, there are annual trainings held in February. See Prescribed Ecological Burn Program | Natural Areas Notebook (oaklandnaturalareas.com) for more details.