Saturday, June 5, 2010

Why I Spray Herbicide

I never walked Blue Jay Barrens before buying it. Of course, it wasn’t called Blue Jay Barrens then, it was just an old, rundown farm. My wife and I looked at the house and decided it was acceptable, but all I knew about the land was that I was getting a 100 acre back yard in a geologically unique area. I had no intention of doing any real management on the property. I was just sure that there was a lifetimes worth of fascinating nature out there to be discovered.

Things changed when I began finding rare plant species that had their continued existence threatened by shading or crowding by other species. One of the guiding principles of conservation planning is to put the land to the use for which it is best suited and this land was proving to be best suited to rare species and ecosystems. As a professional planner and the owner of the property, I felt responsible for seeing that the rare plants were protected. Besides, I thought it was all fascinating.

This was all pre-internet, so I didn’t have easy access to information. Restoration Ecology was a developing science and it was hard to find anyone that could give you sound advice. Wildlife managers recommended planting all sorts of exotic plants, but that didn’t seem to be quite the right thing for this property. I started gathering everything I could find about rare ecosystems and their management and developed my first management plan. The greatest management need was to remove the plants that threatened the rare species I was discovering.

People are often surprised when they ask me what kind of work I do to maintain rare ecosystems and I reply that I kill plants. Except for some time spent maintaining the trails, all of the physical work I do is related to removing unwanted plants. I cut and I pull and I spray all manner of aggressive plant life in order improve conditions for the rare natives. Most of the plants I’m after are non-native invasive species, but I also remove common native species in favor of the rarities. If I had a choice, I’d just let nature take it’s course, but we’ve made such a mess of our native ecosystems that I can’t see myself not doing all I can to save what I’m able to save.

I thought a long time about the use of chemicals to control invasive plants. After much study and thought, I decided that glyphosate herbicide, commonly known by the brand name Roundup, would benefit my management efforts. I chose to use glyphosate because of its benign interactions with the ecosystem. The glyphosate molecule is absorbed by plants and is designed to bond with a specific enzyme within the plant. This glyphosate bond prohibits the enzyme from forming a normal bond that would allow production of amino acids responsible for making proteins required for plant growth. The result is a plant that starves to death. These enzymes are only found in plants, so glyphosate only interacts with plants.

Glyphosate does form a second bond and that is with clay particles. This bond is formed when any glyphosate touches the soil and is so strong that the glyphosate is essentially neutralized. Plant roots are unable to absorb glyphosate bound to clay, so neighboring plants are not affected. In order to work, glyphosate must be applied directly to an actively growing plant. The glyphosate bound to the soil is degraded by microorganisms into naturally occurring soil substances.

Without the use of glyphosate, many invasive plants would be uncontrollable and I would have to face the fact that much of what is special about Blue Jay Barrens was destined to be lost. NOTE: The photos used in this post show areas of grass and rare plants that would not exist today if succession had been allowed to follow its natural course during the past 25 years.


  1. Very interesting and makes a lot of sense. I am just learning about 'succession' as it relates to the wilds of Cape Breton, and find it fascinating. I can certainly comprehend the need for more proactive restoration ecology. ~karen

  2. Great post - I think too many people assume any use of chemical is incompatible with conservation. Your post not only shows this is not true, but also that restoration ecology is nearly impossible without it.

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  4. Karen - I agree that the study of succession is fascinating. There's still so much to discover about the mechanisms in play that allow plants to move into new areas of suitable habitat.

    Thanks, Ted.

    Katie - You've picked an interesting subject to study. The delineations between conservation, preservation and restoration are still being hotly debated. There is often very little difference in the activities required to achieve any of the three conditions. If I were to decide to save what already exists, as is, on my property, the actions I would have to take would be no different than what I’m now doing. If I just let things follow a natural pattern, my property would be destined to become mature woodland.

    The species I am dealing with and their demise by loss of sunlight has been well documented. Shading by developing woodland is not a cyclic event, so there is not a possibility of periodic blooming and replenishing of viable seed. Once woodland is established, it is expected to remain unchanged for centuries. The next peek of sunlight would probably be the next time the woods is logged, and by that time there wouldn’t be any viable seed left in the soil. For information on longevity of seed in the soil seed bank, I would suggest the book Seeds by Baskin and Baskin.

    Some people describe preservation as an effort to save a little bit of our natural heritage for future generations to enjoy. I know that there are plants growing here that are only found in a limited number of locations, and many of those locations are not protected. I have placed restrictions on my deed that prohibit develop of the property. When I die, the property will have the best assemblage of plants and animals that I can provide. What happens management wise will be up to someone else. Maybe in a hundred years this will be known as Blue Jay Forest.

    One of the enjoyable things about this type of management is the fact that there are so many unknowns and variables and opinions and options. If hands-off is the key, I’m secure in the knowledge that dozens of nearby properties are proceeding down that course and whatever damage I do to my place will be of little consequence. If what I’m doing is correct, then I’m discouraged, because my tiny property is insignificant when compared to the tens of thousands of acres surrounding me.