Weeds won't wait. Desirable plants are growing, but alongside them grow the un-wanteds. Nuisance weeds, which are simply plants out of place, are not the concern though; it is the invasive plants that are of concern.
Invasive plants like Japanese knotweed and garlic mustard are not native, have taken up residence here and are growing out of control. They are gaining ground in our yards, along streambanks, in fields, woods, waters and wetlands.
Now is the time when we may be eager to rip, tear, dig, mat or mow to get rid of these harmful plants -?but - it is very important to choose the right control method for the right plant in the right place. Before beginning any project to remove invasive plants, learn about their best management practices.
Handpull garlic mustard prior to seedset. Take care to also remove roots. After pulling, tamp down-soil to minimize disturbance. Bag plants and dispose of at the transfer station. Never compost garlic mustard.
Best management practices, or BMPs, are used in many different situations: stormwater, agriculture and forestry, for example. When used in invasive plant management, BMPs take into consideration the type of plant, its biology, how it spreads, where it is growing, how abundant it is, known control and disposal techniques and management objectives. Using BMPs sets a plant manager up for success. Starting an invasive plant project without knowing the proper control methods can make the infestation worse and lead to even greater damage and frustration.
Landowners and natural resource managers use a variety of techniques to manage invasive plants. Generally these include physical, mechanical, chemical, biological and cultural means. Physical controls involve handpulling or matting. Mechanical methods may include clipping, digging, excavating, dredging or mowing. Chemical treatment depletes plants of stored food and kills the plants at its roots. Biological controls introduce a host-specific predator to an area to feed on plants: the Galerucella beetles attacking purple loosestrife, for instance, or sterile grass carp munching on milfoil.
In addition to these methods, cultural controls may be a suitable option. Cultural controls involve evaluating the infested area for sources that could be causing the infestation to worsen and then mitigating those causes, such as reducing the use of fertilizer on lawns or fixing leaking septic systems to minimize nutrients fueling plant growth. There is also the option of taking no action, which can at times be the most appropriate action depending on the size of the infestation and availability of management techniques, time and resources.
There is no silver bullet for managing invasive plants and there is no one-size-fits-all approach. Often using a combination of control techniques is necessary and a commitment for sustained management is a must. Controls typically need to be implemented for at least three years, sometimes even more. The length of time it takes to successfully eradicate an infestation depends on the species, viability of seeds in the soil, persistence of roots, how widespread the infestation is and whether there are nearby sources of the same plant that may cause reinfestation.
After deciding on the appropriate control technique, it is critical to use proper disposal methods. Composting terrestrial invasive plants is generally never advised. For example, Japanese knotweed must be placed in a sealed plastic bag and taken to the landfill. Mulching with weed-free seed or mulch or revegetating with non-invasive plants are two alternatives to put your project on the path to success.
Call the Adirondack Park Invasive Plant Program at 518-576-2082 to learn more about which invasive plants to be on the lookout for, the proper BMPs to use to control them and for recommendations on non-invasive plants to use in landscaping and ornamental ponds. Also ask about community-based programs operating in your area or how to start one.
Though invasive plant management can be overwhelming, it can be done successfully. It really is worth doing and you can make a difference. Whether it's garlic mustard or goutweed, giant hogweed or Japanese knotweed, or one of the more than 40 invasive plants known in the Adirondack region, informational resources are available to help guide you through the management process.
Though it may be a bittersweet endeavor, managing invasive plants can be gratifying for you and is good for the environment too. Learn, plan, then ready, set !
Eye on Invasives is a biweekly column that spotlights a top invader when it is easiest to identify. Hilary Smith directs the Adirondack Park Invasive Plant Program, a partnership program housed at the Adirondack Chapter of The Nature Conservancy in Keene Valley. Find out more about this award-winning program online at www.adkinvasives.com.