Dear Avant Gardener

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Why Managing Gophers Wisely Matters

And how mountain lions — AKA pumas, cougars, and panthers – earn their poster child status

Official Florida panther license plate (source: Florida Fish and Wildlife)

Dear Avant Gardener, What do you advise regarding gophers? I have a lawn where they make a mess and they destroy any vegetables that I plant in the ground. Also, can you tell me the price of your class? I can't seem to find it anywhere on your website. — Sally, Temecula, CA

Anything but rodenticides! Not ever, please. Rodent poisons — usually, anticoagulants that cause animals to die from internal bleeding — cause serious harm to animals that eat rodents they kill or weaken with a non-lethal dose. These poisons build up in the bodies of predators like owls and mountain lions. They are also deadly to pets and humans, killing 3,000 people in the U.S. in 2021, including 2,300 children.

Nor do I recommend trapping and relocating. It is inhumane, putting animals in dangerously unfamiliar surroundings and often separating families. (Relocating wildlife is also illegal without a permit in California and elsewhere.)

One analysis looked at squirrels relocated from suburban yards to a forested environment. After just 88 days, 97 percent had died or disappeared. Research on other species shows similarly poor survival rates for wild animals who are forcibly relocated. The squirrels “were getting nailed by predators because they didn’t have escape routes,” says wildlife biologist John Hadidian, who co-authored the study. “When a squirrel in your backyard is threatened by cats or hawks or other predators, they know exactly where to go. They have a map in their head of where they live.” — ​The Humane Gardener​

At the California Botanic Garden, Plant Records Manager James Reed, who also manages the garden’s gopher population, recommends the ​Gopher Hawk​ trap to kill gophers humanely. He uses it only when pocket gophers interfere with the garden's mission, which includes inspiring the public about native plants and conserving rare and endangered native plant species.

I'm wondering about ways you can minimize destruction — e.g., keeping them out of paths and the vegetable garden — while continuing to live with them. The key to this approach is understanding the behavior of your gopher species, which is probably Botta’s pocket gophers (Thomomys bottae). The good news is that Botta's gophers are very territorial, so they quickly reach a maximum number in an area. According an ​LA Times​ report on a talk by ecologist Paula Schiffman of Cal State Northridge,

One report estimates maximum capacity at 30 an acre. Whatever it is, if you have been living with gophers for a while, your gopher hotel is probably full. They are territorial. You won’t have more.

As for our Transform Your Yard course, the twelve-week live, virtual course that starts in February will be $899, less early-bird discounts TBD. The self-paced, pre-recorded version will be $299, less occasional discounts. You can sign up for the waiting list to be among the first to receive updates and discounts ​here.​

I definitely don't want to poison them as we have a lot of owls and hawks in our area. Gopher snakes and owls could be helpful, but they won't accept my dinner invitation. In any case, we have spent quite a lot of money over the years trying to get rid of gophers, but they always come back. Are there benefits to having gophers?

Absolutely, gophers are beneficial — especially to the disappearing California grasslands, where plant species are rapidly becoming extinct. In fact, the disturbance they cause is a defining characteristic of this ecosystem:

The remarkable extent of soil disturbance and the profusion of burrowing animals that produced them were described by virtually every early chronicler of California’s wildlands, starting with Sir Francis Drake in 1579. — ​Fremontia: Journal of the California Native Plant Society​

In fact, some plants depend on this soil disturbance the way other plants depend on periodic fires.

Native grassland plants have coexisted with burrowing animals in these environments for millennia. Therefore, it is not surprising that some natives have ruderal (disturbance-adapted) tendencies that enable them to exploit the churned up soil in these natural disturbances. Certain natives have distribution patterns that indicate tolerances, or even preferences, for growing on patches of recently disturbed soil. Examples include fiddlenecks (Amsinckia spp.), dobiepod (Tropidocarpum gracile), California lotus (Acmispon wrangelianus), as well as California mustard (Caulanthus lasiophyllus) and its endangered congener, the California jewelflower (C. californicus).

For other native species, such as alkali sacaton (Sporobolus airoides), burrow mounds act as safe sites, where interactions with competitors are less intense than in the surrounding grassland matrix. The vertical mixing caused by so much animal digging also adds dynamism to native seed banks. Previously buried dormant seeds become exposed when new burrow mounds are created. — ​Fremontia: Journal of the California Native Plant Society​

Unfortunately, disturbance now often favors invasive plant species in the wild. And the elimination of gophers from much of their historic territory threatens other species that use their burrows, like the burrowing owl and California tiger salamander (a listed threatened species). Allowing gophers to share your yard could protect these native plant and animal species.

Botta's gophers are one of 35 gopher species in Central and North America; they rarely emerge from their burrows.


I am changing my mindset about these little guys and I want to accept them and value their role in the ecosystem. For a start, I could plant natives that the gophers don't like within a yard plan and perhaps gophers wouldn't lurk around too much. I already have non-natives they seem to avoid, including apricots, tangerines, oranges, lemons, and Asian pear trees, as well as rosemary, bottlebrush, daffodils, lantana and oleander. I found a list from Mostly Native Nursery of gopher resistant plants. I don't hate the idea of providing some sustenance for them, but I'll have to think about that a bit more. A long time ago I read a book about the Green Gulch Farm and Zen Center and I remember that they did not kill gophers and they were growing vegetables. If I planted mostly natives, would this issue take care of itself?

The Zen of living with gophers. I love that. I discovered a video in which Tenshin Roshi of Green Gulch Farm talks about how he struggled with gophers for 35 years because they were "wreaking havoc" in his lovely moss and grass-covered garden. He tried various repellants to get them to move — rabbit urine, a beeping spike, even rock music.

I confess to you that I had not been mindful of being a gift to the gophers and that the gophers are a gift to me. … My practice with the gophers has not been very mature. … Now, I finally pretty much surrendered to them and instead of trying to coerce them out of the yard, … now … I’m their servant. — ​San Francisco Zen Center​

Each day, Tenshin Roshi rakes the gopher mounds and moves the big rocks they push out to piles around the perimeter of the garden. Of course, raking gravel or sand is itself a form of Zen meditation. But Tenshin Roshi is talking about practicing giving — being the giver, the receiver, and the gift itself — as fundamental to Zen.

I don’t have the patience to rake gopher mounds each day. In fact, just listening to Tenshin Roshi’s slow speech and long pauses was an excruciating test of my limited patience. However, like Roshi, I view my work in the garden as a gift to the plants and animals that live here and the presence of the plants and animals are a gift to me.

Just chatting with you has made me more enthusiastic than ever about working in my yard to make it more eco-friendly, less needy for maintenance. Still, I will need to limit their intrusion to some degree using barrier wire and/or above-ground vegetable plantings. Previously I planted roses in metal wire cages which kept the gophers out, but the roses didn't flourish as much as I had hoped. I know I can put hardware cloth under the raised beds, but I think it needs to be stainless steel if it is a vegetable bed. Galvanized steel hardware cloth is much cheaper, but contains lead which might leach into the soil.

Yes, horizontal barriers under raised beds and even turf grass, are indeed effective, whereas vertical barriers are not. Gophers tunnel under vertical barriers, according to Roger Baldwin of University of California Davis, who specializes in human-wildlife conflict. To keep paths and small turf areas gopher-free, Baldwin recommends installing hardware cloth horizontally under the soil and extending it above the surface of the soil around the edges.

Baldwin recommends ​three quarter-inch grid hardware cloth​, small enough so they can't squeeze through yet thick enough gauge (e.g., 16 or less) so they can't chew through. Standard chicken wire is not sufficiently thick, nor is most standard half-inch hardware cloth.

Smile, breathe and go slowly. ― Thích Nhất Hạnh

— The Avant Gardener


Why, How, Wow!

Why?

Before we registered our car in Florida, I spent months looking at all the hundred-plus specialized license plates that support various causes. Manatees? Native plants? Sea turtles? In the end, Pete and I decided on the Florida panther plate. Saving this endangered predator will require creating vast wildlife corridors to accommodate their large ranges.

Florida panthers are territorial and solitary, unless a pair is mating or a female is raising kittens. They use pheromones and physical signs (like claw markings or feces) to define their territory. Males roam much larger territories than the females. A male can make a territory more than 200 to 250 square miles in size. — ​National Wildlife Federation​

In addition to requiring large territories, predators like the panther are often what finally mobilizes the public against chemical controls. Remember DDT and bald eagles? Toxins like DDT then and anticoagulants today build up in the bodies of animals at the top of the food chain. Last year, concern about the toll on mountain lions — the same species as the Florida panther — contributed to a law further tightening restrictions on use of rodenticides.

Some of California’s most iconic wildlife are victims of toxic rat poisons. The ​California Department of Pesticide Regulation​ has documented unintended poisonings in at least 38 different species in California, including the imperiled ​San Joaquin kit fox​, ​northern spotted owl​ and ​California condor​. P-22, the Southern California mountain lion who made headlines for establishing turf at Griffith Park, had long suffered from rodenticide poisoning before he died last year. — ​Center for Biological Diversity

How

Like pocket gophers in California grasslands, most native “pests” are actually valuable contributors to our ecosystem. For example, as Humane Gardener Nancy Lawson ​points out​, ants spread spring ephemeral seeds, wasps create nesting material for birds, moles till the soil, and groundhogs create habitat for numerous other species — reptiles, amphibians, foxes, skunks, opossums, snakes, and raccoons.

Personally, I am attempting to share my yard with many native critters, drawing the boundary for most at the exterior walls of our homes. Our small properties host voles, shrews, foxes, chipmunks, squirrels, coyotes, bobcats, the occasional groundhog, white-tailed deer, and a gazillion rabbits.

I create additional boundaries to protect our health and happiness, trying to make decisions based on science, not tradition — or advice from financially-motivated pest control companies. We keep deer away from newly planted shrubs with minty ​Deer Out​ repellent in the summer and temporary fencing in the winter. We plan to build a raised bed cover like the one below to protect our small vegetable garden from rabbits and groundhogs. And I advised Zoe, who lives in the Lyme disease capital of the country, to use a variety of methods to make sure the areas where she spends time in her yard remain tick-free.

If you’re embracing biodiversity, as I hope you are, I encourage you to question knee-jerk antipathies and reconsider where you draw the boundaries between yourselves and the wildlife in your area.

Chris Lane builds these custom raised bed covers for customers in Rhode Island. (Source: Facebook Marketplace)

Wow!

Beth Pratt of the National Wildlife Federation made the Southern California mountain lion known as P-22 the poster child for its #SaveLACougars campaign. With a transformative grant from philanthropist Wallis Annenberg, the campaign raised $87 million to build the first-ever wildlife crossing created to save a population from extinction. Vast quantities of native plants are being grown while construction teams build the bridge across the 101 freeway in Los Angeles. According to the project's landscape architects, Living Habitats,

Once constructed, the Wallis Annenberg Wildlife Crossing will be the largest of its kind in the world and will set a new standard for urban wildlife connectivity. For this project to succeed beyond the substantial engineering feat required to span the 101 freeway, the new landscape-driven solution must be understood as an integral, living, and evolving element. The soil and vegetation that combine to create this vital habitat go well beyond conventional fill or structural overburden to create an ecological stitch from one side of the freeway to the other. — ​Living Habitats

Source: Annenberg Foundation

Related Resources


Gorgeous Native Gardens

Photo: Caitlin Atkinson

Each week, I hope to share some eye candy in this new section of the newsletter. This week's garden at the Pasadena, California home of designer Todd Nickey of Nickey Kehoe appears on the cover of the July/August issue of Architectural Digest. The garden first caught my eye on Instagram, where I follow garden photographer and native plant lover ​Caitlin Atkinson.​

Working in tandem with landscape designer Fi Campbell, Nickey’s first order of business was installing the focal pool, which they initially surrounded with various grasses. “Watering the grass was a nightmare, and it kept dying anyway, so we ripped it all out,” he says. For the next iteration, he and Holcomb reimagined the garden utilizing mostly native and drought-tolerant plantings — selected in consultation with the plant specialists at ​Hardy Californians ​— in a limited palette of purple, white, yellow, and green. — ​Architectural Digest