by Katherine Howard
Garlic mustard, a leading plant invader, is now in your backyard, along your favorite walks, virtually everywhere in Newton! The problem will get worse and worse if we do not act. It’s time for a declaration of war!
Garlic mustard is only one of several plant invaders we need to tackle. The Newton Conservators Spring 2009 Walks schedule includes invasives’ removal sessions at various Newton parks and conservation areas. We are continuing and expanding the efforts of a group of people who have been working for a decade to control these pests at Dolan Pond and parts of the Charles River walkway. There is also much you can do about this problem in your own backyard and neighborhood.
Garlic Mustard (Alliaria petiolata) was brought here from Europe, probably as a garden herb. It is high on the federal/state lists of invasive plants. It can cover vast areas rapidly, particularly forested areas, shading out other plants, chemically altering the soil to inhibit germination of competitor seeds, and destroying the habitat of native insects such as butterflies. Fortunately, in areas where it is just gaining a foothold, getting rid of it does not require much effort. It is a biennial, very easily identified and easy to pull in May and June, when the second year plants are flowering. If not removed, each plant will scatter hundreds to thousands of seeds later in the season, many of which will germinate the next year and flower the year after that; the seeds can remain viable for several years. See the USDA garlic mustard website.
It is essential to pull these plants before they release their seeds (each plant can have 350-7900 seeds!), and dispose of them in the trash (not with yard waste or compost). And check the area later in the season, because a plant that did not flower early can “bolt” later and produce seed pods.
Last spring I roamed my neighborhood and pulled up whatever I could. It was easy and satisfying, and a fun way to interact with neighbors (some of whom may have wondered why I was in their yard removing their flowers)! Now a troop buildup is needed, and I plan to post signs and gather a group of neighbors for a mid-May “pull.” By taking responsibility to attack this plant in our own neighborhoods we can beat this invader back!
Japanese Knotweed (Polygonum cuspidatum; Fallopia japonica) was introduced to the US in late 1800’s as an ornamental, It has spread throughout the entire country, altering natural ecosystems and seriously damaging waterways. It spreads rapidly by seed and rhizome, forming dense 10-foot tall thickets that crowd out native vegetation. A member of the buckwheat family, it has smooth, stout stems that are swollen where the leaf meets the stem, and is sometimes mislabeled “bamboo.” Branched sprays of small greenish-white flowers in summer are soon followed by small winged fruits, with small, triangular, shiny seeds. Once established, knotweed is very difficult to eradicate. At Dolan Pond and along the banks of the Charles River, pulling individual plants and cutting them back repeatedly to promote root fatigue have proven to be effective ways to tackle the problem, but continued effort is essential.
Eric Olson, a Brandeis University ecologist, and Ted Kuklinski of the Newton Conservators have remained steadily involved in these removal efforts. We are working with the City’s Planning Department and the Conservation Commission to ensure that the removal of invasives in the parks and conservation areas and near wetlands is done properly, is well-planned and well-documented. We must not inadvertently harm any vulnerable habitat.
We want to recruit you for an upcoming “battle”! Check our upcoming events for invasive pulls.