The Invasive Plant Problem
Invasive plants pose a great risk to the health and safety of our home landscapes and natural environment. Invasive plants, when left unchecked, can quickly colonize an area and displace the native flora that would normally fill the same niche. The problem with this succession is that invasive plants reduce the biodiversity of plant life and as a result reduce the biodiversity of wildlife that our environment can support. They also present safety issues with causing premature death in trees which leads to safety concerns especially in denser human development.
Before & After
Methods of Control
With invasive plants, traditional methods of mechanical cut backs, hand pulling/weeding alone are not enough to help control their growth. While hand pulling can help set back growth of plants like Asiatic bittersweet and glossy buck thorn in their immature states, any root material that breaks off in the soil can come back as a new plant. Cutting woody invasive plants alone does little to hinder growth. Cutting woody stems generates multiple new shoots of growth at the cut point and only temporarily interrupts its growth cycle.
Precision Painting
Green Abundance does not enjoy the use of synthetic herbicides in our landscape. We clearly see their widespread misuse in the residential and commercial landscape setting. With that said, we understand systemic (root killing) herbicides are often the most effective approach in controlling invasive plant growth. To this end, Green Abundance invests in equipment that allows us to judiciously and precisely paint very small, but focused amounts of systemic herbicide, typically Glyphosate (Round-Up) and Triclopyr.
The majority of our invasive control methods employ topical foam applications. The foam carrier dramatically reduces run off from the plant site when applied to cut stumps. This allows us to minimize our herbicide use while also protecting nearby native plants from harm.
For sites where foliar applications are necessary we use a combination of tools. For smaller infestations or where native vegetation is still a dominant component of the site, we employ hand held foaming applicators. These create the largest droplet size and significantly reduce drift (indicated in picture gallery). The foam consistency is closer to a Jackson Pollack painting than an aerosolized spray. For larger contiguous stands of invasive plants (often Japanese knotweed stands or bittersweet thickets) we use low volume electronic pressure regulated back pack systems to maintain consistent applications with largest droplet size possible.
To be clear this is NOT an organic approach and is not appropriate in garden beds used for food production.
Management Timing
To maximize the use of our systemic herbicides, it is crucial to properly time their application. As a general rule of thumb, most woody plants are best treated outside of the spring growth cycle. For eastern Massachusetts this roughly works out to be a June-February management time frame.
The reason we do not perform our herbicide applications in the spring is the herbicide needs to translocate to the plant’s root system. During spring, sap flows are sending energy up from the plant’s roots out to their branches to grow new leaves. This upward flow of energy works against a systemic herbicide making its way to a plant’s roots.
There are some plants like Garlic Mustard Weed whose live cycle is over by the summer. In cases like these spring management is necessary for their effective control.
Maintenance
Our methods of controlling invasive plants average 90-95% efficacy rates for plant control. With this in mind we always recommend at least one follow up visit during the next season.
This allows us to:
1. Retreat any plants that may have survived from a first pass.
2. Treat invasive seedlings that have newly germinated in the space. For areas with a lot of invasive pressure, there is likely a high volume of invasive plant seeds in the site’s soil seed bank. Treating invasive plants at this immature stage of growth is much easier and efficient way to prevent a larger problem from developing again.
For some landscapes, annual or biannual visits are recommended to keep invasive plants in check.
Follow up visits are usually handled by a single technician at a much lower cost than initial cleanings.
Painting Gallery
Invasive Plant Films
Invasive Plants of Massachusetts
Norway Maple
Native to the much colder regions of Northern Europe, the Norway Maple in New England is on a tropical vacation in comparison. Norway Maples leaf out sooner than native maples, grows quickly, produces a dense canopy, and produces an allelopathic chemical in its roots to further reduce competition.
Once commercially cultivated and grown for its vigor and hardiness, it remains a common plant throughout the suburban landscape and has moved into our more natural spaces as a result.
Its leaves are somewhat similar to the native sugar maple leaf, but tend to be broader and produces a milky sap when the leaf stem is broken and squeezed. It also has a tighter bark pattern versus the broader and deeper ridges of the sugar maple.
Winged Bark Euonymus
Another understory shrub that rarely finds a location it doesn’t enjoy. Full sun to full shade, dry to moist it can be found everywhere in our forest and woodland edges. Dispersed by birds its spread is far and wide.
Only recently has the plant been removed from commercial cultivation. Up until 2009 it was commonly planted in landscapes due to it being easily pruned, having brilliant red fall foliage display (hence other common name of Burning Bush), and its general bullet proof nature.
Winged Bark Euonymus is unlikely to be removed from our landscapes due to its historical wide use and continued persistence. At this point it is important to quell new growth in our more naturalized spaces.
Characterized by its opposite patterned elliptical leaves, and the thin ridges along its bark (Winged Bark). It is very easy to spot in the fall as its leaves turn brilliant shades of red.
Poison Ivy
Green Abundance does not consider Poison Ivy an invasive plant. It is a native plant that does provide value to wildlife especially in the form of its vitamin C rich berries. We consider it problematic to humans. We only look to control its growth in the home landscape where it poses a risk of potential human contact. In this way we work to create a buffer between areas of human traffic and naturalized spaces where we leave poison ivy to grow untouched. We do not touch poison ivy or offer mechanical removal services. We will only manage it with foliar applications of a systemic herbicide to kill its growth. Large vines are cut towards the base and painted with a systemic herbicide at the stump. The vine is left on the tree.
More common invasive plants that we manage:
Invasive Bush Honeysuckle
Autumn Olive
Mugwort
Black Locust
Multiflora rose
Japanese barberry
Climbing nightshade