The Early Invaders
by Josh Palumbo, Forest Management Coordinator
I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!
Late winter at Wintergreen is a time of anticipation, looking forward to the wave of plants about to erupt from the soil. It just so happens that the first vegetation to begin their growth towards the sun are a couple nasty invasive plants, garlic mustard and coltsfoot. This edition of the Nine Minute Naturalist will go into depth on the unique life cycle of two non-native plants that call Wintergreen home.
Garlic mustard is the bane of the Wintergreen forest, covering acres of our deepest forest where few invasive plants can compete. This plant comes to us from Europe, brought over due to its value in cooking and in seed form as hitchhikers. This plant is a biennial (it has a two-year life cycle) giving it a competition advantage. Garlic mustard reproduces only via seed, which can be viable in the soil bank for up to 10 years. Seeds germinate in early spring and form rosettes, a low growing clump of dark purple to green scalloped shaped leaves. Rosettes survive the first-year over-winter in a green (chlorophyll rich) form, which enables it to grow and habitat space well before most native species can emerge. Second year leaves are more triangular and begin to grow in early spring up to 3-4 inches per week. Flowering will occur in second year plants from late April to June. Plants grow up to 4 feet in height and produce 400-7000 seeds per plant. A dense stand of garlic mustard will produce up to 12,000 seeds per yard that will be dispersed via wind or attached to animals and humans. To add to their advantages, researchers have found chemicals are released that inhibit growth of plants in their immediate area. Once established, garlic mustard is near impossible to eliminate. On a site-by-site basis, garlic mustard can be controlled by mechanical removal or chemical application. Applying chemicals such as Roundup needs to be done with extreme caution at the height of plant growth to ensure you are not spraying desirable native plants.
While garlic mustard is quite the pain in the Wintergreen landscape, it is quite the useful edible plant. The greens are laden with vitamins A, C, E and some of the B vitamins. It also contains potassium, calcium, magnesium, selenium, copper, iron, manganese as well as omega-3 fatty acids. The flowers, leaves, roots and seeds are all edible but become bitter as they age. It is bad for the environment but quite good for the heart!
Coltsfoot is another introduced species from Europe. It is unique in that its flower appears before the leaves are formed, usually in March and April. The small 1-inch flowers are on tall stalks with reddish scales. The flowers are a bright yellow color and stand out in the drab backdrop of late winter. They appear similar to dandelion flowers from a distance. By May the flowers give way to white seed heads that look like fluffy cotton balls. When the leaves finally appear, you will understand the common name coltsfoot. They grow up to six inches across in the shape of a colt’s foot print. Unlike garlic mustard which can grow in the dense shade of our forest floor, coltsfoot will be found along our roadways or any other full sun environment. They are particularly fond of any disturbed site. The sides of the road at Wintergreen provide the perfect home for this invasive plant. Once established, coltsfoot is hard to remove. Hand pulling is effective in wet soil conditions so that you can get the whole root. Any piece of root left can grow into a new plant. Herbicide application is most effective. Application of Roundup needs to be done in a careful manner if the infestation is amongst plants you desire to keep.
Coltsfoot is also beloved as a medicinal plant. The plant contains mucilage, bitter glycosides and tannins which are thought to give the plant anti-inflammatory properties and act as a cough treatment. The flowers can be eaten in salad or combined with honey and added to tea to calm a cough. Although the leaves are bitter, they have been used in salads or as an aromatic tea. Another name it goes by is coughwort due to its implied medicinal qualities.
Despite my dislike for these two early emerging plants, it is good to see green life peaking out through the forest leaf litter. Once you take a second to be excited over green plants returning to our landscape, sharpen your identification skills. Now is the time to be able to identify and eliminate these undesirable plants before they can establish themselves alongside those plants we love.