Natives, aliens, and invaders

By Beth Sullivan

The actual growing season is coming to an end. Plants are beginning to store their reserves for next year, and use their last bits of energy for seed production, ensuring a future generation.

We have different stewardship chores at this time of year, different management strategies to maintain the preserves as ideal (or close to it) habitats for native wildlife. As we think of our fall work, we are assessing the problems of non-natives and invasives-planning the best way to eradicate or keep them in control, and do so in a way that is safe, but also efficient.

Hard to resist the beauty of the beast- Porcelainberry

With invasives gone, beautiful wildflowers can re-establish

Non-native is not always invasive

Non-native, in itself, is fine. Aren't most of us more or less non-native? Many of our decorative shrubs and flowers and fruits and vegetables are not native to our area, but we welcome them into our gardens and they have the courtesy to stay in check. Elsewhere, however, some non -natives have chosen to go crazy and become invasive to the point of overwhelming our native flora and degrading habitat. It leaves us with some hard management questions. When we manage a preserve for ideal habitat and promotion of native species, both plant and animal, we need to decide how much invasion to tolerate, what the effect is on the habitat, and how to deal with it. The use of herbicides continues to be a sticky issue. I don’t think there is any one of us who enjoys using chemicals of any kind, but when faced with the daunting prospect of tons of bio-mass needing to be removed or controlled, sometimes it becomes necessary. When we have had to resort to the use of a chemical treatment, we do so using the best professional guidance. The right treatment for the right plant in the right area. We consult with DEEP and USFWS among others. Professionals are studying the effect of certain treatments on regrowth, seed banks, root regeneration, and species diversity and also investigating how long a chemical remains active in the soil.

At Dodge Paddock it was absolutely necessary to eradicate the Phragmites. After two years we have a handle on the management, yet they persist, and we will as well. In the meantime restoration has begun. If native plants can be encouraged to recolonize, they may be able to fend off invaders.

Phragmites choked the wetland in 2012.

In 2015 the area is regrowing with native plants and invites more wildlife. Photo by Jeff Callahan.

At Knox Preserve we have spent hundreds of hours clearing walls and removing aggressively invasive vines and shrubs. The habitat had been badly degraded. At this time of year, as plants start sending their sap back to the roots, it is the best time to use a targeted spray on the leaves of invasives. It will be transported directly to the roots, kill the plant, and the chemical itself will degrade , usually well before the next growing season. Again, not an easy decision. But one that needs to be made. Each season we see great improvement. But we cannot let our guard down.

Invasive Porcelainberry took over walls and shrubs.

We reclaimed the walls and natives offer natural beauty.

Start the battle at home

When we garden in our home plots it is always easier to pull a weed, keeping an invasion in check before it becomes overwhelming. It pays to know your plants, know the invasives and understand the best way to control them. Think before you purchase certain plants that may be beautiful but invasive and still on the market: Purple Loosestrife, “Burning Bush” Winged Euonymous, Barberry, Porcelain-berry. Autumn Olive, Multiflora Rose and Oriental Bittersweet were once favored ornamentals that we now fight. If you have these plants in your yard, if you cannot eradicate them, think about pulling off seeds and pods to prevent their spread by birds and wind.

If you find Swallowwort,  remove the pods.

An area of Swallowwart properly treated.

We are in the season for Fall planting; choose wisely, think native.

You can learn more about invasive plants at the Connecticut Invasive Plant Working Group.

Photographs by Beth Sullivan, unless otherwise indicated.

This post originally appeared September 28, 2015