Home & Garden
Year ago, my friend Stan Millstein, a protohippie from Brooklyn who, like many, moved to L.A. in the 1960s turned on, tuned in and dropped everything. In L.A., Stan joined a C.R. or consciousness-raising group, which was essential a bull session. This group seemed primarily interested in tackling ethical problems.
They decided to look at mouse traps and figure out which one worked best and was most ethical. They looked at a lot of mouse traps (this is before the sticky ones). Was it better to let the mouse die slowly in a trap or to smash it to death instantly? What of poisons? Would the kids get to them or the cat? In the end and after much discussion, Stan said, “We decided to live with the mouse.” Mice aren’t all that bad and we could probably all be better about cleaning the kitchen and sealing up the food.
I don’t think that Stan knew anything about IPM (integrated pest management) but, whether he knew it or not, he had become, at least, to some degree, a proponent and perhaps a practitioner.
IPM goes back to the years following the Second World War and, like many good things, began in California. The essential idea, which many of us now take for granted, was that a multi-pronged approach was preferable to one of search-and-destroy. (Even the CIA figured out that it was better to strategically take out a leader than to annihilate an entire population, but that’s a little Machiavellian for this discussion.)
After many years of development, IPM as a science and practice has organized itself to the point where it has six clearly segregated tactics or prongs, if you will. With apologies to the experts, here is my take on each.
1. Determine acceptable pest levels. Do you really need to kill the mouse? If there are a thousand mice, would it be O.K. to use a method that might be far less toxic or otherwise abhorrent but would only kill 95 percent of them and leave 50 for the cat? Destroying 100 percent of anything is usually far more rigorous than a lesser percentage and often involves collateral effects (such as poisoning yourself and your neighbors) that can be avoided by agreeing on acceptable levels of trouble.
2. Integrate preventative cultural practices (buy a cat). This is about asking good questions. What grows best where you are? Before treating a plant with a pesticide, can you remove the mildewed leaves. (We’ve done this in our garden where powdery mildew has wrecked havoc upon our squashes, over spraying, I think). Using different wood to build the house (that the local termites don’t like.)
3. Monitoring. IPM is about studying and responding intelligently and in a well- modulated manner to a perceived problem. This may involve studying insect populations, mold growth, rates of growth of whatever you have, reactions to interlopers or enemies by your subject. By studying insect reproduction or food gathering biology, it’s often much easier to develop a strategy of control. Monitoring or study is the cornerstone of IPM.
4. Mechanical methods. In the building trades, removal of infested timber would be a mechanical method. In the garden, physically removing snails from plants is another. These are least toxic and often easy but always require monitoring and understanding the limitations of these approaches. No mechanical method can remove all of your pests but might be one part of a very effective system of control.
5. Biological controls. A very exciting part of IPM is the use of competing organisms or other biological influences to control your subject (enemy?). We haven’t figured out how to get ants to fight off your termites and then go away (did you know that these insects are natural enemies and wage full-scale war upon one another?) but this will surely come. Many folks know that a carton of ladybugs bought at the nursery can be deployed among the roses to consume those pesky aphids, but did you know that this was IPM? Use of microorganisms including bacillus and fungi to control pests are also a part of this category.
6. Chemical controls. Notice that this is last on the list and a good thing too. Every year, the EPA pulls another few chemicals off the shelf as we discover the long-range ill-effects of various giant molecules (often found cancerous) as another hundred move into our stores and industries. Pesticides vary in toxicity greatly and range from those made from the lovely Chrysanthemum (pyrethrum and its variants) to Nicotine (they told you it wasn’t good for your health right?). Some pesticides merely prevent some essential biological function such as making of a new skin (chitin in the case of the mighty termite) and do not, therefore require nearly the toxicity of something designed to outrightly kill the thing straight off. In an IPM method such as a termite bait trap, one might use one millionth the dose of a chemical otherwise pumped into the soil in a less elegant method. The more strategically we can apply the use of a chemical and the less toxic that chemical to the overall environment, the better for all concerned.
So how can this methodology be used to address termite issues at your house? Some of this is already happening whether you’re aware of it or not. We are slowly moving away from high volume spraying or soil saturation of carcinogenic pesticides toward those with lower toxicity and, most recently, toward the use of baiting stations. I see these as I walk around houses from time to time but until contacting Bill Quarles at Berkeley’s Bio-Integral Resource Center I didn’t realize just how they worked.
BIRC publishes a range of periodicals and books that provide practical how-to information on pest control for garden and structure that still manage to provide plenty of scientific data for wannabes like me. The IPM practitioner from Jan/Feb of 2003 is all about the science of controlling termites and included a healthy dose of termite biology. Did you know that over 45 species of termites inhabit the U.S. (a blessedly small number given their near 4,000 species total) and roughly two-thirds are considered pests (I assume that most of this must involve the consumption of our buildings and the like.)
As of 1990 research in this volume (I guess we backdate that another few years for publication delays), these 30 or so species ravage upwards of 2.5 billion in homes, barns and bridges each year. I guess we can safely double that number to allow for inflation, making it about the budget for the National Science Foundation.
Curiously, most of the methods discussed in Dr. Quarles newsletter were within grasp of a moderately intrepid homeowner (can it be you, dear reader?). Quarles even specifies some relatively safe toxicants (just a tax oxymoronic, I guess) such as boric acid, that can be bought locally and handled with relative safety (though gloves and a respirator would be well advised).
This issue gave fairly simple instructions for construction of a bait system that involved mostly common items like PVC piping, cardboard or wooden stakes. Petri dishes were called for but I suspect that you backyard warriors can find substitutes as no single part of these systems appeared to be pivotal once the essential concept was borne.
A common method in monitoring for termites intriguingly involved setting wooden stakes in a perimeter about the house and then checking them monthly for activity. One method involved using stakes with a hole bored through the center and a cork plug (termites love cork). I guess you’d have to make those with your 18-inch-long drill bit!
Once these were attacked, the article suggested that some operators could then drop the “recruits” (yes, and the ironies are beyond perfect) into a manufactured bait station built using perforated piping and poisoned cardboard).
The “recruits” eat the cardboard, carrying a low level of poison bait back to their home below ground. Termites leave a pheromone trail and will be far more likely to return in numbers to this bait station if they’ve first been shown the way in this manner (thus the term, recruit). Once home, termites will regurgitate and share the poisonous munchies with their mates, a behavior known as trophyllaxis. One of the tricks of this method is to find a poison and a dosage that won’t alert the termite or kill them prior to sharing the spoils (so to speak). A well-designed system allows time for thorough distribution of the poison and death of the entire colony (ugh). That said, I’ll now stump (ahem) for a totally different approach.
Modern housing design requires fundamental “mechanical” prophylaxis regarding termites and a range of other pests. In the case of termites, foundations must be tall enough so that no wooden part of the structure is within eight inches of the ground (used to be six inches but just changed in California). Termites are both xenophobic and photophobic. They like to hide and will avoid coming into view or into the light. They like short stubby foundations that allow them to attack and consume wood without exiting from the safety of the ground. If they must, they will sometimes build masticated tubes of cellulose that allow them to climb the foundation but, like the burglar, they will move on to the next house if yours is a bit too much trouble.
If you keep woody debris and scrap lumber out of your crawlspace and scoop a bit of the excess soil away along the side of the foundation so that you have a few clear inches below the yummy wooden structure, you are likely to be well protected, remembering all the while that monitoring is the hallmark of IPM.
In the end, I side with Stan. I really don’t mind termites. Actually, I hear they’re rather nice with a little olive oil and salt and in a world food crisis they’re especially delicious.
I say, leave the termites alone and build to suit. The alternative is to keep on poisoning the planet until nothing tastes good.