Introduction
As many who work within the field of conservation or have listened to a few lectures regarding the subject may know, there are many different threats to the small pockets of intact ecosystems that remain globally. Each year these biomes shrink costing us in ecosystem services and overall health and wellbeing. One of the greatest factors in this ecological degradation is often highlighted as the spread of invasive species. Invasive species range from plants, animals, to even bacteria or fungi that are not originally from a region originally but were brought over accidentally or purposefully by humans for various reasons but end up outcompeting native species and have little to no predators in this new environment. Some often regard native plants of an area that have aggressive reproductive tendencies to also be “invasive” plants despite being native to the same region we are trying to save.
In college I was taught the typical information and mindset towards invasive plants, that being that they are taking over our lands and need to be exterminated, castrated, or down right controlled to protect the little residual intact ecosystems/biomes that remain. I remember this concept really having an impact on other students. It brings on a sense of doom and defeat which students are indeed correct to feel as the “war” on many of these invasive species is unwinnable when you give it some thought.
It is one of those things that you don’t really think about or worry about until you are taught why this is an issue and shown a real life example. At that moment the veil of bliss is now snatched from over your face and you are awakened. This moment for me was realized when I was working as a park ranger for a summer. I was allowed to burn and spray for various invasive plants. I soon realized that invasive plants cover much of our private and public lands and that land managers can make small progress in some areas, but are limited in other infested areas due to the topography, hydrology, or manpower to get the job done and make sure the issues don’t come back. It was at that moment that I realized we would never really get rid of these species as it takes a whole community to improve these issues.
In my state, there is far more private land than public land and here in the United States the overall culture is hyper-individual and profit driven first rather than community driven in most cases. I often see some of the worst land management practices by private landowners who cannot identify the plants on their property and will most likely spray the ones they don’t know with herbicides as they fall into the “weeds” category. Although I am young into my career in conservation it took a short time for me to lose faith in landowners to protect the remaining ecosystems around me. Many farmers and ranchers are too ill equipped either financially or mentally (training wise/workload) to give proper attention to these issues thus leading to a collapse in initial management.
While it is not my intention to insult the average farmer or rancher I must document what I see. Many farmers or ranchers can’t put great money on the table for their family and have to spend even more time farming and ranching more acres with greater “efficiency” leading to further degradation to their land as it is being pushed to its productive limits. It is in scenarios like these where invasive plants find their opportunity to utilize a highly disturbed or unmanaged area. Sure, there are programs out through the NRCS like CRP which gives cost share to producers to plant areas back to a native stand of grasses and forbs, but many practices within this program have too strong of limitations to be attractive to producers or require too much maintenance for those who are allowed to plant areas which were not ecologically ready to be planted.
I could go on and on about the woes of modern man here in the United States and their impact on various other species but I will try and stay focused. The point of this blog is to share the idea that “invasive” plants are not evil in nature. These plants are just doing what they were meant to do… live! I say this with a bit of hesitancy as I am by no means encouraging the planting of invasive species by choice or to solve a problem, but to voice concerns and criticism at the way in which the conservation field addresses the subject and the practices which we as conservationists seem to promote to the laymen. I really want to take a step back and make sure that when you are addressing invasive plants that you look at it from all angles and without any hate or malice within your heart. Consider the end goal of your restoration project (what are you wanting to achieve and why). Understand how things got so bad in this area in the first place, how was the species introduced to this area and what was its purpose? What is keeping this species you want to remove here? What ecological functions is this species providing to an area (there is always at least one)? Lastly, have you considered that you may never be able to fully get rid of this species?
1. Understand the End Goal
I recently have had a change of heart regarding the management of invasive species. This was due to reading a Toby Hemenway blog article from 2011 titled, Native Plants: Restoring to an Idea. Toby is the late author of the popular permaculture book Gaia’s Garden (which I have read and recommend in a YouTube video). In his blog article he talks about how the term “invasive species” is flawed and demonizes plants that are really just doing what they were put here to do… live and reproduce. We are quick to hate plants like bindweed and kudzu but don’t really look at corn and beans the same way. While I will acknowledge that corn and soybeans don’t just pop up in a new area and take over, they are culturally invasive in the way we grow them today here in the United States. These corn and bean fields are very low in diversity and are sprayed with various fertilizers as well as herbicides and pesticides for greater production which then reduces the insect diversity and soil diversity. These factors basically make these areas ecological deserts which promote temporary travel corridors for wildlife but offer little habitat or nutrition outside of raw calories.
Invasive species are taking advantage of the destructive land management practices brought by Euro-American producers and development companies. It is the creation of a fire suppressed landscape and hyper-disturbed landscapes in combination that have lead us down the road we are on today. This is why things like woody encroachment and invasive species really have a foothold on the landscape. Toby goes on to write in his article that this concept of humans altering the landscape for their own benefit is not new and that Native Americans were doing it even when climate conditions were unfavorable for what they wanted to achieve/maintain. He often questions why certain plants are considered invasive when dispersed by humans, but are not consider invasive when dispersed by animals like birds on their own over long distances.
Ecosystems are notoriously hard to break into as a new species because all the spots are taken, all the niches are filled. In the circumstance of today we often see that many seats are open as their patrons are away for the time being or have been forcibly removed. This opens the door to some new and unwanted guests who are planning to stay for a long time. Much of our understanding of an ideal landscape is actually just an idea. When thinking ahead in what you would like to achieve for your project understand what you are really trying to achieve and that there is technically no “right” answer as nature is always changing this is why mass extinctions have happened numerous times in the past. Now create your idea of a “restored” landscape.
2. How Did it Get This Bad
After realizing that the landscape will never truly be exactly the way it was 200 years ago here in the United States it is important to understand how things got to be the way that they are. The answer is disturbance and erosion. Many of the invasive species were actually brought in by people or entities as to prevent significant erosion or to try and cover up poor land management practices like over grazing. This is why invasive species like kudzu, Japanese honeysuckle, Johnson grass, autumn olive, and yellow bluestem are all prominent in across various rural communities. It took a perfect storm of disturbance and conditions for these plants to become dominant in the landscape like they currently are.
Once you look into the history of both the region and the site and figure out what was going on, it becomes easier to spot why an invasive species took over and what its job is at the location it has established itself in. When you understand the niches that these plants are fulfilling it allows you to replace these plants to a species that is able to play more nicely with other species and prevent such an opportunity from occurring in the future.
3. What is Keeping This Species Here
As we briefly touched on in the past few points, it is super important when removing plants for further development or restoration to think about the factors that have kept them in this location. Is it due to a lack of fire or grazing? Is it the loss of various other woody shrub species, or has the area lost the species that was specialized in that specific job? The answer is most likely all of the above. Every species has its kryptonite; nothing is immune to the humbling force of nature. Once you figure out the conditions that some of the species need to keep their spot as king in their domain it may not be so difficult to de throne them. Do understand though that it takes a community to make real strides in conservation. If your neighbor refuses to see eye to eye with your mission, all the work you do will be in vain or you will spend much of your time keeping out the offspring from the plants on the neighboring property.
4. Understand That Some Species Are Here to Stay
Lastly, just accept that sometimes the species you want to get rid of is just here to stay for the time being until your neighbors figure out what the issue is. The solution to a problem often lies within the problem as is a common permaculture thought process. In some cases it may not be worth the time and energy to remove. Often times some species are hard to control with mechanical and chemical control and many require farming an area to get it to go away (example, Old world bluestem and Sericea Lespedeza) to remove it from the soil and help reduce its presence in the seed bank. Often times the use of chemical to try and control these species can actually harm and reduce the species you are trying to save surrounding application site making it somewhat counter intuitive for some managers.
Conclusion
If you break down the idea of an invasive species it is really a negative term in speech. The word invasive is negative and promotes negative feelings towards plants that have no real choice but to exist. I have heard the term used by land managers to describe aggressive native species who have a tendency to take off in population if gone unchecked.
While I do understand and support the notion of protecting and promoting high diversity, sustainable ecosystems I do find it important to specify that you should factor some non-native plants being in the mix to some degree. There will always be a niche to fill in common government funded restoration attempts (like common CRP seed mixes with the same lazy mixes/seed plans), many of the species which filled these niches have been gone for some time and would take a longer attempt to try and allow those plants to reestablish and regain their control. Some things are able to be removed and others will take greater perseverance, it is up to you to decide what your limit is and what exactly you are restoring an area back to. The planet is never constant and the only thing that we can certainly rely on is change.