Writing Life

America’s love affair with grassy lawns has been blamed for numerous environmental problems, including rapid diminution of the nation’s water supply. With this in mind, my wife set out three years ago to transform our tiny back yard into a haven for drought-tolerant plants that can survive on a fraction of the water necessary to keep a lawn alive.

It took nearly a year for all of this newly planted flora to thrive and become dense. The result was lovely: lots of lush Mexican sage, and rosemary, and other hearty herbs that sip rather than guzzle water. She also dotted the yard with small trees and woody plants that have long roots and can drink from deep within the soil and thus do not need daily watering.

As the landscape matured, however, we began to hear scratching sounds in our walls at night. At first, these sounds occurred only at long intervals and didn’t last very long. But over the next year or so the nighttime scratching gradually became louder and less intermittent. Clearly, our house had a rat problem. At first, we tried to solve the problem by simply keeping the house as clean as possible. We figured if there was never any food, or even food crumbs, lying around inside, the rats would eventually give up and go elsewhere. Unfortunately, even when we kept the house spotless, we still had scratching in the walls. The final straw came when we discovered that a rat (or rats!) had urinated underneath the oven. Now, whenever we turned on the oven, it heated the urine and stunk up the whole house. We pulled the oven out from the wall and scrubbed the floor beneath vigorously. We also cleaned the oven thoroughly, inside and out. But the ghost of rat urine past returned ever so vaguely whenever we heated up the oven. It was disgusting. We owned a housecat but, being deaf, she was no help whatsoever with the rat problem. A phalanx of rats could have danced a conga line behind her without attracting her attention. And so we called a friend of ours who works in pest extermination and asked for help.

After inspecting the interior of the house, he seemed puzzled. The place was clean, and there wasn’t any evidence of a massive infestation. He mentioned that he had an ultraviolet light in his truck that might be instructive. “If I bring the light in and turn it on, every spot of rat urine in your carpet will be visible as a bright purple splotch,” he told me. “Would you like to see that?”

I implored him not to bring in the ultraviolet light. “I don’t want to see purple splotches every time I look at my rugs,” I said.

“You don’t understand,” he said. “You won’t see the splotches again after I turn off the light.”

But I shook my head and told him, “Believe me, once I know where those splotches are, I’ll see them every time I look at the carpet, with or without the light.”

And so he spared me the ultraviolet treatment and continued hunting for the source of our rat problem. He discovered it when he stepped out into the backyard. One glance at our lush new drought-tolerant landscaping and the exterminator looked as if he had seen a 200-pound rat charging at him. He pointed to all of our herbs and woody plants and told me, “This is a veritable rodent resort.”

It seems that we had installed exactly the kind of landscaping that rats love best. They don’t generally eat grass and they cannot hide in it, so a nice tidy lawn holds no allure for them. But a yard full of thick, dense ground cover provides them with a place to sleep and keep cool during the day. What’s more, my wife had installed a gurgling water fountain in the backyard as well as numerous bird and squirrel feeders. “You can’t feed birds and squirrels without also feeding rats,” my exterminator friend told me. “If you don’t want to get rid of the landscaping, you need to at least get rid of all the animal feeders.”

He also wanted us to get rid of – or at least drain – the water fountain. Because summers in Sacramento are so hot, there are few puddles for rats to quench their thirsts in. That’s why rats frequently show up in the filters of backyard swimming pools. In an attempt to drink from the pool, the rat falls in and drowns. Our fountain was much more rat-friendly than a swimming pool. It was shallow and the water flowed almost all the way to the top of the reservoir, meaning that a rat could drink from it with little risk of drowning. The exterminator insisted that eliminating the food and water in the yard, as well as thinning out the landscaping a bit, would probably solve the rat problem. He surmised that the rats were gorging on squirrel and bird food in the night and sleeping in our walls during the day. The scratching we heard was probably rats waking up and preparing for their nocturnal foraging raids on the backyard.

“But don’t worry,” the exterminator told me. “You probably don’t have as many rats as you think. One or two rats in the walls can sound like 20.” He then proceeded to do what he called “some exclusionary work,” which consisted largely of using steel wool to plug a few holes in the basement air vents. He also set up five “snap traps” in the basement and three “glue traps” inside the house. The snap traps kill rats and mice instantaneously but they can be dangerous to house pets so are used only in areas where cats and dogs do not roam. The glue traps have gooey floor mats that present no real danger to cats and dogs but keep the rat stuck in place until it can be removed.

Twenty-four hours after their installation, three of the snap traps had caught and killed a rat. The indoor glue traps, to my relief, never caught anything (I wasn’t anxious to dispose of a live rat trapped to a sticky floor mat). After that, we never heard another sound coming from the walls.

It turned out the exterminator was right. The rats in our walls were mainly just interested in the food, water, and lodging available in the backyard. By eliminating the food and water, thinning the brush a bit, and plugging up a couple of holes with steel wool, we reclaimed our walls from the rats.

Our story had a happy ending for everyone but the rats. But if you are pondering switching from a grassy lawn to a lush landscape of drought-tolerant plants, remember that a drought-tolerant yard can also tolerate a lot of rodents. In fact, it can be downright hospitable towards them.

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