Saturday, October 18, 2008
More to a flower than meets the eye (warning: shamless self plug)
As many of you know I run a business called Out on a Limb where I provide golf courses with various environmental services. I was recently planting a buffer zone at a high end Toronto golf club and was asked by a member "why did you choose those plants?".
There are many things to consider while planning a buffer zone, I personally like to follow the Permaculture principle of planning for at least three beneficial characteristics resulting from the one project. In order to do this successfully each site must be considered on an individual basis. The slope/grade, soil type, playability, aesthetics, biodiversity, plant function and possible maintenance requirements should all be considered while planning for the specific planting site. Some of the benefits realized by considering the above features of a planting project include erosion control, habitat corridor linkages, nutrient filtration, beautification, fuel conservation (no more mowing), shading (important role of many urban projects) and many more.
The debate between native and non-native material is ongoing, when it comes down to it I evaluate material for buffer zones based upon the functions the client wants from the project. For example - if they are looking for something that is primarily aesthetically pleasing I'll use plants that produce showy flowers. This is where the designer, according to that permaculture principle mentioned above, must consider other beneficial characteristics of the plant for this particular site.
Lets use the native Blue Flag Iris (Iris versicolor) for example, Iris's are commonly used in moist planting areas, and produce large flowers that golfers love. They are low enough to the ground that they wont pose too much of a difficult feature to play. Iris's can help define a hole by offering a visual reference for yardages or common out of bounds areas, and of course they provide nectar to bees. Another lesser known but extremely beneficial characteristic is their ability to filter pesticides. Now I'm in no way condoning or promoting the irresponsible use of pesticides that would lead to pest control products leaching into a body of water, what I am saying is that we should employ specific species capable of removing these chemicals if they are released into the environment, it would be irresponsible not to.
“Studies from golf greens have shown that 5 percent to 10 percent of the total pesticides applied are lost in runoff. In worst case conditions, this figure can be as high as 30 percent,” says John Clark, a professor of veterinary and animal science at UMass (taken from this article). “We have identified plant species that can reduce the amount of certain pesticides in soil by up to 94 percent in the greenhouse.”
Out of the ten herbaceous plants tested Blue flag iris was the clear winner, able to reduce levels of the insecticide chlorpyriphos (EPA Info here, fact sheet here) by 76 percent and levels of the fungicide chlorothalonil (Info here and here) by 94 percent in soil after three months of growth.
I will continue to write articles about plants that could be used to fulfill the many functions that we need them to on golf courses. I'll be tagging them under the function titles of erosion control, habitat corridor linkages, nutrient filtration, beautification, fuel conservation (no more mowing), shading (important role of many urban projects) and many more.
For more information about bioremediation techniques used on golf courses check out the links below:
The Bioremediation and Phytoremediation of Pesticide-contaminated Sites - Prepared by Chris Frazar National Network of Environmental Studies (NNEMS) Fellow
Pesticide Residues in Grass Clippings Raise Concerns - BNET
Selection of Plants for Optimization of Vegetative Filter Strips Treating Runoff from Turfgrass