Q. I use mulch to control weeds along the foundation of my house, and understand that wood chips are not good as they may attract termites. Some of my friends are using treated wood chips that are supposed to pose less of a risk. I would like to hear your opinion.
- --- Ursula; El Dorado Springs, Missouri
- ---Howard in Bucks County, PA
And you are already poised to prevent that balance of power tipping in the wrong direction by removing all that termite food outside. Although people think they can use those EXTREMELY carcinogenic old railroad ties to frame garden areas without attracting wood eating pests, the opposite seems to be true. The nasty chemicals used to preserve those ties (and old power poles and pressure treated wood) leach out over the years—and may not have been all that effective to begin with, because infested railroad ties are the #1 mode of transport for those treacherous Formosan subterranean termites down South.
Pine needles are an equally bad idea close to the house. As are all the different wood mulches, including treated ones, and—surprise!— non-wood mulches like stone, and plastic covered with anything. As Bill Quarles, director of the BIRC (the Bio Integral Resource Center; www.BIRC.org) in Berkeley, California, has often warned in his publications and on our Public Radio show, the most common type of termite, the subterranean variety, needs moisture to survive, and any mulch running right up to the side of a house will provide that necessary moisture underground. (The lone exception is compost, the only mulch we recommend without any hesitation or qualifiers.)
Yes, a wood mulch will also feed the army as it marches towards your mansion, but when pressed last week for which was more important, Bill quickly answered "moisture; they can get by without wood or other cellulose for a while, but moisture is crucial. If you want to keep subterranean termites out of your house, have a mulch free area all around."
This, of course, makes the recent trend of 'decorative mulching' with shredded bark and dyed trash wood even more ill-advised and foolish than it appears on the surface. Which is really saying something, as these mulches already starve plants, invite nuisance molds to irrevocably stain your house, and rot the trunks of any flora they touch.
(Gasp! NOW I get it! A group of evil geniuses like Victor Von Doom, Lex Luthor and The Joker must be behind the mulch trade in America! Quick! Where's my Justice League signal device? I have to alert Aquaman to this treacherous team-up before The Menaces of Mulch realize I'm on to them!)
Anyway, after you move all the mulch away from your home, there are three other things you can do to prevent those "Little Rascals" from eating your entryway. (Readers: Do you suppose that our friend Howard has named some of his Rascals 'Spanky' and 'Alfalfa'? Do you think they might have a really little dog named 'Petey'?!)
One: Call your local county extension office and ask which kinds of termites are active in your area. (Just search the words "Cooperative Extension" and the name of your state; the website for your state's main office will have lists of all the local offices with contact info.) Almost everyone has to deal with the subterranean variety, but some of you will also have "drywood termites" to contend with. These don't need cover to reach a home—they fly to your structure and enter through cracks and crevices, just like the Asian ladybugs and other 'home invading insects' we discussed a few weeks back. Luckily, their colonies are smaller and cause much less damage than subterraneans.
Two: Inspect your home regularly for signs of forced termite entry. To learn how to do this properly, we heartily recommend you obtain the BIRC's special publication on termites, which includes a big section on inspections. (It's under "special publications" here: http://www.birc.org/pubrep.htm) With subterraneans you're mostly looking for 'mud tubes'. These creatures hate to be exposed, so they utilize a little Termite Corps of Engineers to build distinctive looking tunnels of mud that allow them to cross from the sheltering earth into your inviting eaves. Drywood termites give their positions away when they kick out piles of their sawdust-like 'frass' onto your floor.
And three: Consider installing monitoring stations. Also called 'bait stations', they are widely available and perfect for the do-it-yourselfer. You pound these things into the ground surrounding your home, flip the lid and put in some termite-attracting bait, like cheap pine or moist cardboard. Then you check them on a regular basis for signs of infestation. If you DO find little thick-waisted subterranean Rascals chewing away, you add something to the bait that slowly kills the colony, like a diluted solution of boric acid, an insect growth regulator or a chitin inhibitor (which prevents the young ones from successfully molting into adults). This bait will be taken back to the colony, where it will eventually kill the queen.
Note: it is very important to use something very gentle and slow-acting to eradicate the colony. If you hit them hard, the workers will die before they can get the poison back to the nest, where you were hoping they would spread it around. The workers may also be repelled by strong stuff and avoid the stations. AND these dilute and/or slow-acting baits are very safe to have around children, pets and the environment. It may take a few months to wipe out the colony, but die they will—without any harm to you and yours.