Invasive Plant Removal 101

The What and the Why of Invasive Plants

When discussing invasive plant removal, we must first understand the what and the why before we get to the how. What are they and why should they be removed from our landscapes?  

Invasive plants are non-native species that spread rapidly, out-competing and displacing native plants, which causes harm to local ecosystems. Where we see native plant populations decline we also see a decline in native insects and other wildlife, a problem that radiates all the way to our food webs. So when we remove these plants, we aim to protect and restore biodiversity and native habitats. Yes, it’s true that after such removal our landscapes usually look a thousand times better. And while I’m all for beautiful scenery and curb appeal, our cause for removal should be, at the root level, an environmental one.  

Methods of Mechanical Invasive Plant Control

A Park Pride Greener Good Volunteer Day focused on invasive plant removal at Riverwalk Atlanta led by Michael Hudgins.

Methods of control are usually divided into thee categories: mechanical (hand pulling), chemical, and biological. Below are tips for mechanical removal, which are appropriate and safe for use in local parks: 

Determine Priorities 

Often, it can feel overwhelming to know where to begin. While we know the overall goal is to protect and restore native habitats, what exactly in your landscape needs to be protected first? Maybe it’s your garden or your children’s play area. If you’re a park steward, maybe it’s the ever-narrowing trails being encroached upon by invasive plants.

Priorities can rank differently from one site to another, but often tree health comes in at the top of the list, as it should. English ivy and other non-native smothering vines will shorten a tree’s life considerably, causing it to come crashing down, threatening your house and safety. From a broader view we must protect our tree canopy, something that makes Atlanta so special as the City in the Forest. So yes, start by protecting the trees! 

Make a Plan of Attack 

Work from the edges. Contain the spread (protect unaffected areas) and close in on the infestation rather than beginning in the middle. An invasive plant problem is rarely solved in one day and can sometimes take years of intermittent work depending on time and resources. Progress can be swallowed up before you know it if a methodical approach is not used.  

Choose the Appropriate Tools 

Research which tools are best for the invasive plant(s) you’re taking on and how to use those tools. Common tools for this work include loppers, hand saws, pick-mattocks, shovels and weed wrenches. My favorite weed wrench is the Uprooter (theuprooter.com). 

Work with Intention 

Before a plant is removed it should be accurately identified as a non-native invasive. While it’s true that different invasive plants like to hang out together, usually there are some native plants in the mix as well. It’s easy to go into full obliteration mode and wipe out everything in sight to achieve that cleared, mission accomplished look but we should remember one of our overall goals: native biodiversity. By preserving the existing native plants in a work area, we allow them the chance to spread and establish a foothold now that there’s room to grow.  

Get the roots. When removing an invasive plant, the entire plant should be removed by the roots. Many plants, when damaged but not uprooted, engage in an act called suckering. A response to trauma, a plant will shoot up new growth from its base resulting in several main stems where there was once only one. If this happens throughout a workspace then you’re left with a much bigger problem than when you started.  

The less disturbance the better. Naturally, removing invasive plants is very disturbing to the ground. We should strive for only necessary disturbance. No need to pick up every stick, branch, and log. In fact, we disrupt the too-many-to-count organisms that are very beneficial to the ecosystem when we tidy up just to tidy up. That being said, many freshly cut woody invasive plants can re-sprout if left spread across the ground, even if just a fragment. Time should be taken to make sure those pieces are gathered and put in the proper place.  

Where is the proper place to put the invasive plant material once removed? That depends on your location, but generally I feel the best option is to leave it on site, somewhere it can dry out, decompose, and eventually return to earth. Transporting the material before it’s had a chance to dry out can spread it to unaffected areas and the logistics of hauling it off can be an unnecessary use of time and resources. Fruits and seeds from invasive plants should be bagged up and trashed (not composted) when possible. 

Monitor and Manage 

After removal, monitoring and management of that space is required. Otherwise those same invasive plants can reestablish themselves and other opportunistic invasives can swoop in to fill the void. One of the most exciting parts of invasive plant removal is to see which native plants emerge afterwards. Native seeds that have been sitting dormant in the soil now have the space and sunlight they need to grow. Without proper after-care those native plants can easily be wiped out again by the ultra-competitive invasive plants. Many people want to install native plants of their own choosing, which can also be fun, but should be done with two things in mind: is it native and does it belong in that local ecosystem? 

 

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It should be noted that invasive plants did not arrive on their own. They were introduced by humans, some with the best of intentions as with kudzu, which was introduced to America in 1876 as a solution to combat erosion. The word invasive can evoke notions of battle and feelings of fear. But it’s not simply a native vs. non-native issue. It’s about the health of the land and the ecosystems that are the backbone of our food networks. And while there is no intent by a plant to invade and conquer as the term suggests, I do like the word invasive because it conveys a sense of urgency for the removal of these plants.