Our natural resources team uses pesticides to moderate the spread and propagation of invasive plants. It’s part of our integrated pest management initiative, used to maximize invasive species removal and minimize associated costs. In this regard, “costs” include not only expenditure and labor, but more importantly, environmental and human health.
I was asked in a phone interview for my Valley Forge conservation position if I was alright with the use of pesticides. Of course, this was a moral question. Pesticides are evidenced to have acute adverse effects and chronic adverse effects on the reproductive, nervous, respiratory, and endocrine systems of animals that have had heavy and/or consistent pesticide exposure. In the environmental realm, these externalities cannot be overlooked, and are often cause for inquiry. I was hesitant to say that I was fully on board with the use of pesticides, but agreed to use them in the fields, if only to see how they were being applied.
Here at the park, we have a variety of pesticides, each suited for different uses. Some are non-target, killing or damaging any and every plant they come into contact with. Some target only woody plants. Some cannot be used within a certain distance of water sources. Some cannot be used if there is a chance of rain within the next hour—some the next four hours. Adjuvants are added to reduce drift of the pesticide in air, work as surfactants etc. Pesticides are treated with extreme care, and never used in excess. What is important to note, is that, if used in compliance with these rules, pesticides are effective tools in mitigating the spread of pests and invasives. Pesticides, if not used in accordance with these rules, or applied on the wrong plants, can be harmful and unsafe.
I’ve since come around to the use of pesticides because I know that they are simply tools, and very effective ones. All tools can be wielded irresponsibly though, and it is up to the user to not only be knowledgeable of the tool, but also know how and when it should be used–if it is going to rain soon, or if it is being used on crops for consumption, or if it will even prove effective in combating the spread of a certain plant species. This sort of cost-benefit weighing is ubiquitous in environmental science and conservation management.
One “tool” use I was recently considering, is the systematic placement of concrete substrate along the ocean’s bottom, in order to foster growth of coral communities. If added in areas that favor coral growth (e.g. ideal temperature, current, sunlight exposure, salinity etc.) this method could be very successful. If done without careful placement or without proper knowledge of its efficacy, concrete substrates are just another form of ocean pollution. It is this fine tightrope that conservationists have to walk in order to introduce novel ideas and practices to real-life use and management.