The Terminte that Ate Houston, and Other Gardening Urban Legends

The tall tale started, as all good tall tales do, in Texas. Homeowners in Houston circulated this warning on the Internet: “After the hurricane in New Orleans many trees were blown over. These trees were then turned into mulch and the state is trying to get rid of tons and tons of this mulch to any state or company who will come and haul it away. So it will be showing up in Home Depot and Lowes at dirt cheap prices with one huge problem; Formosan Termites will be the bonus in many of those bags.”

The warning had all the hallmarks of a great urban legend: A real catastrophic event (Katrina), combined with a plausible scenario (downed trees and construction debris getting shredded by the ton), result in an extremely icky consequence to unsuspecting suburban homeowners. Open a bag of mulch from the hardware store and hundreds of termites will come running out and head straight for your foundation! I can just imagine the headlines: Katrina Termites Devour Texas Neighborhood.

There’s just one problem, of course. It’s not true. Sometimes I just delete these kind of alarmist Internet warnings without a second thought, but often I’ll go to or and find out the facts so that I can throw a wet blanket on the fears of the worried aunt or neighbor who sent it to me.

In this case, there are any number of reasons why homeowners don’t need to worry about termites in their mulch. A strict quarantine has been imposed in the areas affected by the hurricane. It’s unlikely that termites could survive the mulch experience—shredding, mixing, bagging, transporting. Finally, large chain stores like the ones listed above are most likely to monitor the supply chain for problems like this.

That’s not to say that all mulch is entirely sterile, or that it should be. After all, the reason gardeners use mulch is that it adds organic matter, including some microscopic living creatures, to the garden. In other words, we want mulch and compost to be “alive.” But if you’ve ever bought shredded yard waste or slash from a guy with a pickup truck and a chipper, you know that it can come with a few added bonuses in the form of weed seeds, plant disease, pesticide residue, and even, in the case of one Arcata gardener I know, the spores of a certain illegal and hallucinogenic mushroom. (“Really, officer! It was in the mulch!”) And this is what makes an urban legend so much fun. It’s theoretically possible.

That got me wondering about other garden-related urban legends. I found several that contain at least a grain of truth, and I bring them to you courtesy of the fine people at

Cocoa mulch can kill your pets: True. Well, sort of. Cocoa mulch is made from the shells of cocoa beans. It’s a lovely dark brown color, it helps smother weeds and hold garden soil in place, and it smells like chocolate. What’s not to like? A compound in chocolate called theobromine that is toxic to dogs, for one thing. Now, many dogs will simply avoid anything containing chocolate, and other dogs will eat a small amount that may make them sick but not kill them. Still, if you’ve got a dog who might munch on your landscape, try another kind of mulch. And if your dog does get sick from eating cocoa mulch, dash to the vet. The ASPCA’s website contains several recommendations for treating poisoned dogs, so it’s not a lost cause.

Exploding cactus spews baby tarantulas (or scorpions): False—mostly. There are many variations on this story about a man who brought back a cactus from Mexico, planted it in his garden, and enjoyed it for several months until one day when the cactus burst open and hundreds of tarantulas were flung around the garden. This story appears to be false, and in fact spiders are not known to lay eggs inside a plant. Even if they did, the plant would not explode when the eggs hatched. A scorpion might hang out under or in a cactus, but again, it would not burst apart and scatter hundreds of little garden terrorists. In fact, while any kind of insect might try to hitch a ride on any kind of plant, this is really not the sort of thing you should lose sleep over.

Man Threatens Violence to Get Police to Respond to Garden Theft: False, with some exceptions. I love this story because it contains all of the other elements of a good urban legend, and throws a garden thief into the mix. The story goes that a man noticed someone rummaging around his garden shed late at night. He called the police, but was told that all patrols were busy and he should lock his door. An officer would come when one was available.

He called back thirty seconds later and said, “Hello. I just called you a few seconds ago because there were people in my shed. Well, you don’t have to worry about them now because I’ve just shot them all.” Officers were on the scene in five minutes and they caught the burglars. One officer said, “I thought you said you’d shot them!”

The man replied, “I thought you said there was nobody available.”

Funny story. Not true. But after the tall tale circulated, a minister in Odessa decided to give it a try when he was frustrated at the lack of response to a reported break-in at his church. It didn’t go so well. The pastor was charged with filing a false report and has posted bail while he awaits trial.

Or at least, that’s the story I heard.