I love the spring season and the sudden onset of green that has besieged our landscape. Delight is a good word to describe my attitude toward the bloodroots, spring beauty, geranium and other countless wildflowers appearing on our forest floor. Sadly, I sometimes skew to the negative and with that comes my vitriol for the copious invasives that accompany our native species in our forest. This Nine Minute Naturalist will discuss the invasives in the mustard family that use spring’s abundant sunshine to their advantage and why they are currently the perfect height for you to do something about them.

Being a part of a plant family means you have certain characteristics in common across the board. The mustard family is no different. The most easily identified feature of the family is the flower. The flower features a four-petalled cross shaped flower with two short and two long stamens. They produce pod-like fruit called siliques and the leaves are usually alternate with a basal rosette of leaves. These annual, biennial, or perennial plants offer many edible options from root to tip of the leaves.

Garlic mustard

The first and foremost invader of spring in our forest is the ever-present garlic mustard. This cool season biennial emerges in its first year a rosette of heart shaped, toothed leaves close to the ground. The rosette stays green throughout the winter and develops in the spring to a flowering plant 2-3 feet in height. They produce seed by mid-May and have died by the beginning of July, only recognized by the brown stalks on the forest floor. What makes this invasive species more insidious than other members of the mustard family is its ability to grow under a full forest canopy, its prolific seeding and its allelopathic tendencies. Garlic mustard left unchecked forms a monoculture on the forest floor due to its ability to alter its environment. It releases chemicals that inhibit growth of the plants and hinder beneficial soil fungi.

Wintercress or yellow rocket

Another mustard prominently featured in our roadsides at the moment is wintercress or yellow rocket. This occupier of full sun, roadside environments is not the ecological threat its brother, garlic mustard, is but an occupier nonetheless. The main difference from garlic mustard is the yellow flowers as opposed to white, the full sun environment as opposed to closed forest and the leaf structure. The lower leaves of wintercress are rounded with wavy margins and end with a large, rounded end lobe but progress up the stem to smaller, oval leaves at the top.

Dame’s rocket

The mustard that claims the crown for family beauty is dame’s rocket. This Eurasian introduction has used its beauty to seduce homeowners to want to plant this into many a garden. This mustard boosts robust white to purple fragrant flowers that do contribute nicely to garden aesthetics. Similarly, to the other mustards mentioned, it is a prolific seeder that will out compete most plants in the garden environment. Due to its need for copious amounts of sun, it does not enter the Wintergreen forest. It will make its presence felt shortly on all of our overlooks and roadsides. It emerges slightly later in the spring than garlic mustard or wintercress and will last a bit longer into the early summer. It shares appearance with our native phlox and has often been assumed to be native.

The positive aspect of the mustard growth patterns is that the second-year plants we see standing 3 feet tall on our property spent almost zero energy on its root system. All energy is spent on seed production so they can spread prolifically throughout the environment in May. This is where you come in as a solution. Pull this plant wherever you see it on your property! It is literally standing at perfect height to reach and pull without even bending over. If it doesn’t have seed yet, cast it down wherever you like. If the plant is full of noxious seeds, bag the plant remains up and dispose of it properly. For the next month, these invaders have reached just the right height for you to make a difference.