The American Society for the Prevention of Cruelty to Animals (ASPCA) performs many well-meaning services, and among them is listing on their website the houseplants that are toxic to dogs and cats who may chew on or ingest them. It’s alarming to read just how many houseplants can be dangerous to pets, and of course to small children as well, who similarly are drawn to taste testing unfamiliar plants. Reading the list, one comes to the conclusion that the only truly safe solution lies in ridding the household of plants entirely.
The photographer’s cat, Emmy, sits among houseplants. Photo by Wikimedia user Mattes.
Closer examination of the information available on the ASPCA website and elsewhere reveals that such drastic measures are unnecessary. Houseplants (as their very name implies) have coexisted with adult humans, their pets, and even small children for centuries without calamity. Two factors account for the relatively peaceful, if not entirely harmonious, relationship of flora and fauna under one roof.
One factor is the mostly small amount of toxicity present in almost any plant you care to name, and the other is the common sense tendency of most creatures to cease nibbling on a plant that tastes unpleasant before ingesting a poisonous quantity. Plants manufacture toxins because they are a defense against nibbling animals. A toxin is not deadly in small amounts, while a poison is deadly in any amount. Production of poisons uses up more of a plants’ resources than production of toxins, and therefore plants have generally evolved to ward off nibbling creatures with unpleasant toxins rather than deadly poisons.
This explanation is an oversimplification of the state of affairs, but suffice it to say that if the situation were otherwise, unfortunate humans and animals would be dropping dead to the point of depopulating the planet. They are not. Toxins of some kind are present in most plants, indoors and out, but they exist as a warning to animals not to eat too much of the plant, and thus destroy the plant’s ability to make a living. On the scale of toxic household chemicals, houseplants overall probably weigh in favor of improving the health of people and pets since many of them do valuable service in cleaning the air. Still, no one can fault people for exercising caution when their children or animal friends are at risk, but only for acting heedlessly in reaction to insufficient information.
— Izzy
It can be upsetting for a gardener or homeowner to see mounds of turned soil and sinuously trailing lumps in a lawn that has taken a lot of human care and maintenance over a long, hot summer. Tunneling moles! It can be hard to realize that the little critters, which in the eastern United States most likely go by the name Scalopus aquaticus, are in fact paying you a compliment by visiting your yard to partake of your tasty vittles. You apparently have grubs and earthworms in abundance, signs of a healthy lawn ecosystem, and the moles have appeared to take advantage of the situation.
When moles eat earthworms, they may not be doing you such a great favor since earthworms enhance soil fertility, but they definitely help out by eating the grubs which would otherwise be munching on the roots of your carefully tended grass. There is collateral damage certainly, such as some brown patches in the lawn where the moles have damaged grass roots in their zealous search for grubs, and also the unsightliness to human eyes of the lumps they raise in the lawn because of their tunneling. Rest easy, because the tunnels aerate the soil and will settle back in time.
In Chapter 3 of The Wind in the Willows by Kenneth Grahame, called “The Wild Wood”, timid Mole ventures out on his own into the woods and has a scary time. Illustration from the 1913 edition by Paul Bransom.
Lawn aerator attachment on a garden tiller. Photo by Lovesgreenlawn. Moles happily do the same work at no charge.
People attribute a lot of the damage they see in their plants and bulbs to moles, but really the damage is mostly the work of voles and shrews. Most moles are mostly insectivorous: they usually don’t eat plants. Voles and shrews, on the other hand, will eat just about anything given the chance, though they largely stick to a vegetarian diet. Voles and shrews will also take advantage of the tunnels that moles industriously create. This can make little difference to a gardener who notices a tunnel leading to a freshly planted tulip bed. Arguing before the court of that gardener’s censorious gaze that a mole excavated the tunnel in innocent pursuit of grubs, but it was the voles and shrews who exploited its proximity to the tulip beds to pad their own provisions, often makes no headway with the gardener, who declares war on the oblivious mole.
Traps, poisons, and medieval implements of execution are all pointless and expensive wastes of time and money. You have what moles want, and if after much effort and expense you manage to remove your nemesis from the premises, another will come along shortly to take his or her place. Taking away what the moles want, which means negating the naturally derived soil fertility that earthworms and grubs dig, would involve essentially turning your lawn into the soulless desert waste of a golf course. Green above by virtue of chemicals, but below, in the soil, the home of practically no creatures.
Judy Garland as Dorothy Gale, Jack Haley as The Tin Man, Ray Bolger as The Scarecrow, Bert Lahr as The Cowardly Lion, and Terry the dog, as Toto, in the 1939 film The Wizard of Oz.
Let the moles be, and thank them for their service. Watch out for the voles and shrews, however, and do what you can to mitigate the damage they cause. Get a cat, if that is suitable for you and the cat, and the neighborhood you both live in. Meanwhile, keep mulch and, if possible, snow away from tree trunks, because that denies cover to those creatures while they gnaw at the bark. Clean up leaf litter and brush piles where it seems sensible that these are nesting places and cover for runways. Most of all, let the grass grow to 3 or 4 inches, which should keep the lawn healthier overall, and make those lumps in the lawn less noticeable and not worth fretting about.
― Izzy
