I think we're all aware that each state has a list of invasive species that you are discouraged from planting and in some cases, prohibited from doing so. The main reason non-native invasives are no-nos is because they tend to choke out or inhibit growth of the natives, thereby changing the local ecosystem. Since all living things in nature depend on each other for survival, these changes mean sure death for at least some of our natural inhabitants, including native wildflowers.
Ohio's top ten worst offenders are:
- Japanese Honeysuckle
- Japanese Knotweed
- Autumn Olive
- Purple Loosestrife
- Common Reed
- Reed Canary Grass
- Garlic Mustard
- Multiflora Rose
- Bush Honeysuckles
As a home gardener, I'm not very knowledgeable about identifying many of these. Some hybrids with similar names and botanical genetics are sold in nurseries, and even some of the invasive species are sold in reputable garden centers. So what's a person to do?
Familiarize yourself with the names of those plants that are known to be present in your part of the state and don't buy or plant them. Have a look at photos of their leaves and learn about their habits. You may never become an expert at it, but you'll at least know more than you did before and in this way will become a more responsible gardener. The best place to learn about invasives is to visit your state's Department of Natural Resources website.
Let's move on to the problem child living at Our Little Acre. We have a Morrow's Honeysuckle (Lonicera morrowii) at the southeast corner of our property. Romie says we planted it shortly after moving here in 1977. That's more than 25 years before I became a gardener and to be honest, I don't remember planting it. Whether we did or we didn't doesn't matter now; I want it GONE.
So cut it down or dig it up, you say. Oh, if it were only that simple! An invasive shrub that has a 25-year head start doesn't give it up that easily.
When Max's Garden was created in October 2005, my desire at that time was to tame The Monster in the Corner. This large shrub was out of control, so we cut it back severely. I'm not sure if that was a good idea, because for every branch we pruned off, twelve more grew back in its place. And where Romie used a chain saw to remove a couple of large shoots at its base, even more shot up.
I vowed to keep up with the new growth by continually cutting it out, but it was not about to let the likes of me get the best of it. Finally, last fall, I threw a temper tantrum and ordered Romie to get rid of it once and for all. I didn't care how he did it. I just wanted it out of there.
The chain saw came back out, as did the axe. He buzzed and he chipped and he chopped and he buzzed. I kept carrying the branches to the burn pile, which grew higher and higher, hour after hour.
When he had whittled it down as far as he could go, there remained an ugly conglomeration of multiple hacked-off trunks and branches about six inches high. He'd had enough and we hoped the shrub had too.
But oh noooooo...not this thug. Spring is back and so is the Morrow's Honeysuckle.
After doing some online research, I think we're going to resort to chemical means. I'll be looking for Stump Out ®, which when applied to the stump causes it to decompose rapidly.
Some interesting facts about the Morrow's Honeysuckle came to light while I was looking things up. Morrow's Honeysuckle is thought to release a chemical into the soil that inhibits growth of spring ephemerals and the heavy shade it provides inhibits native plant growth.
Many Cedar Waxwings' wax spots in the eastern United States have taken on an unusual orange hue in the last 35 years, a phenomenon that has been attributed to Lonicera morrowii. The chemical involved in this color change is rhodoxanthin, a red dye found in the berries of Morrow's Honeysuckle. ¹
Sources on Invasives:
Missouri Department of Conservation
Center For Invasive Species and Ecosystem Health
Ohio Department of Natural Resources
Ohio Invasive Plants Council