Eat the Invaders!
As Homer Simpson once said about alcohol, one could ostensibly argue that our mouths are the cause of, and solution to, all of life’s problems. How many wars could have been avoided if an angry man had just kept his mouth shut? How many loose lips have sunk ships? How many marriages brought to an end by words spoken in anger? And what proportion of climate change, habitat loss, the extinction of species and drought is directly related to the rise of industrial agriculture and meat production—in short, the generation of all the things we put in our mouths?
Conversely, most wars are ended through the skills of negotiators, many troubled marriages saved by the words of counselors.
With that in mind, is it possible for our mouths to get us out of some of our ecological worries?
I’ve been thinking about the idea of eating invasive species for a couple of years now, ever since I heard a story on NPR about addressing the growing problem of Asian carp by the simple method of eating them. Last year, when living in Albuquerque, I heard that feral hogs—out of control in many of the Southern states—had started to become a problem in eastern and southern New Mexico. I seriously toyed with the idea of trying my hand at hog hunting, since even a general hunting license isn’t required to take them.
The idea isn’t limited to fish and pigs. A quick Google search of the term invasivore will turn up quite a few interesting pages. For example, at eattheinvaders.org, folks are sharing recipes for knotweed salsa verde (knotweed, apparently, tastes much like tomatillo), stinging nettle frittatas and soups seasoned with pepperweed. At invasivore.org you’ll find another fairly decent collection of recipes, along with an interactive user-generated map (which isn’t very robust yet, but it’s a great idea).
All this thinking really does beg the question: Is eating the invaders —plant, animal or insect—a solution on any level to the problem of invasive species?
The answer to that question is actually pretty complicated. To start to answer it requires an answer to an even more fundamental question: What is an invasive species?
We all have a pretty good idea about the basic concept, and the famous case of rabbits in Australia is a decent example: A species introduced to a place where it fits in surprisingly well, outcompeting the local, native species. Englishman and general dweeb Thomas Austin, upon arriving in Australia, noticed there weren’t any rabbits. Austin liked rabbit hunting, so he asked his nephew in England to send him some. In 1859, Austin released 24 rabbits on his property. The mild Australian winters allowed the rabbits to breed all year long, and the extensive agricultural area in which they were released provided the perfect habitat: land cleared of brush and woodlands, with the local predators already conveniently exterminated. Within 10 years, the rabbit population had exploded to the point where two million were being trapped or shot each year, with no noticeable effect on their population. The rabbits caused widespread ecological damage, denuding the landscape and leading to massive erosion problems. A number of measures were used to try to control the problem (including hunting/trapping programs, a huge fence, and lots and lots of poison). In the 1950s, release of the myxoma virus brought the rabbit population down to about 100 million (from 600 million). Rabbits are still a problem in Australia, and probably will be for the foreseeable future.
While not as glamorous as rabbits we’ve seen something similar happen here in Utah, with cheatgrass (bromus tectorum) and tamarisk (50-60 species in the Tamaricaceae family). Tamarisk, like rabbits in Australia, was introduced in the 19th century, for ornamental reasons and to create windbreaks and stabilize streambeds. Cheatgrass came to the U.S. around the same time, but accidentally, through contaminated grain seed, straw packing material, and in the soil ballast in ships. Both plants spread quickly across the landscape.
According to Dr. David Bowling, an ecosystem ecologist at the University of Utah, there are now no major waterways in the U.S. free of tamarisk. Likewise, there are almost no areas in the country free of cheatgrass. Both species found an ecological void and filled it. Cheatgrass is such a problem for western rangelands – it is poor livestock forage and increases wildfire risk – that the U.S. Department of Agriculture has been looking for an economically viable, edible use for the plant and may have found it. Cheatgrass seeds apparently serve as an acceptable substitute for barley in commercial beer making.
There are some Utah invasives, however, that are unlikely to find wide, popular culinary use. Careless boaters are spreading quagga mussels throughout Utah—boats pick up the mussels in Lake Powell and spread them when they go elsewhere. If they’re paying attention, boaters can remove the mussels and not spread the species around. Left unchecked, these mussels reproduce and spread dramatically, choking out other species as well as causing infrastructure problems such as clogging pipes in dams. Unfortunately, while quagga mussels are technically edible, they don’t taste very good, and tend to concentrate pollutants in their bodies.
For other more delicious Utah invasives, like the Eurasian collared dove, other problems make a growing market demand unlikely. Introduced in the Bahamas in the 1970s, the collared dove spread to Florida by the early ’80s and is now found throughout most of the Americas. They displace rock dove and mourning dove populations, as they are bigger and more aggressive, competing better for food and territory. They are displacing migratory birds that are integral parts of local ecosystems. The chances of someone setting up a collared dove breeding operation for the purposes of selling them for food are slim to nil. And though hunting Eurasian collared doves is legal year-round in Utah – with no bag limit or license needed – it is illegal to discharge a firearm, even a BB gun, within most city and residential areas where most of the birds are found.
Creating a culinary demand for invasives is not a silver bullet. In fact, sometimes it can create a whole new problem. Back in Texas, efforts to control the invasive feral pig through gustatory means have spawned intense hunting and harvesting efforts. Dozens of companies offer guided hog hunts, and many landowners trap and eat hogs that come onto their property. The numbers of pigs is going down. That’s a win for the invasivore argument. On the other hand, feral hog hunting has become a business and deliberate hog releases are now spreading the problem northward into New England.
Perhaps one of the most troubling issues with the concept of “invasive” species is the idea that there’s now no such a thing as a natural, or non-human, landscape. “It doesn’t really matter if cheatgrass is native or non-native,” Dr. Bowling says, “it’s here, and it’s part of the landscape.” We love the idea of a pristine nature, free of our meddling. But the truth is, we are part of the landscape, and we change it in many ways, not the least of which is the introduction of new species that are likely here to stay.
Growing trend or not, it’s unlikely that we’re going make much of a difference by eating invasive species. As a meat-eater, though, I’d feel better about chowing down some barbeque ribs from a feral hog I killed myself than a factory farm-produced chop bought from Walmart. Ethics might not come into play much regarding vegetables, but many of the invasive plant species found in Utah are quite a bit more nutritious than the standard grocery-store veggie fare. Purslane and dandelion, probably growing in your garden right now, have omega-3 fatty acids vitamin A, vitamins B and C, potassium, calcium, iron, and more, which is a pretty good reason to eat your weeds.
The bottom line? The invasivore movement may not save the world, but it sure can’t hurt, either.
Pax Rasmussen is CATALYST’s tech meister, contributing writer and former associate editor.
Timothy Lee Scott challenges our preconceptions about non-native plants.
—by Alice Toler
Invasive Plant Medicine
by Timothy Lee Scott
(2010: Healing Arts Press)
Gardeners know all about weeds; there isn’t a one of us with a cultivated bit of soil who hasn’t spent hours ripping vigorous but unwanted plants out by the roots.
In Invasive Plant Medicine, Timothy Lee Scott proposes a revolutionary rethinking of this combative relationship with plant invaders. Invasives, he says, are here for a reason: They offer us, and the planet, sorely needed medicine. Some invasive weeds “protect the land after improper clearing and use, some renew degraded soils, some cleans the waters, and some break down and clean up toxins and pollutants in the soil and air.” There is, according to Scott, no such thing as a weed—just a plant, as Emerson said, “whose virtues have not yet been discovered.
Some good things about tamarisk
Tamarisk, for example, was brought to the United States from Europe in the early 1800s, but populations did not explode along Southwestern waterways until the great dam-building era of the 1900s. Reservoirs have allowed humans to build cities in arid country, but damming rivers profoundly changes the nature of the habitat along them. Swift-running water carries salt away, but slow-running or still water allows it to build up in the soil during the process of evaporation here in our hot, dry climate. Native riparian plants are not as well-evolved to be as salt tolerant as the tamarisk, and so the tamarisk out-competes them as the soil gets saltier and more alkaline.
Tamarisk also has the ability to concentrate salt in its leaves, so as the plant grows and sheds leaves, the surface of the ground underneath it becomes even saltier. Eradication proponents see this behavior as noxious and monopolizing; Scott believes that it represents the underlying ecology attempting to put itself back into balance after human disturbance, and that disturbing the environment even further by attempting to forcibly control these plants will just result in never-ending escalation and further degradation of the biome. Left alone, he notes, the ecology will invariably re-balance itself, although the adjustment may take decades.
Does this mean you should turn over your yard to the dandelions? As the primary engine of the ecology in your garden, by all means you have the right to control which plants grow in it. Perhaps, though, after reading Scott’s book you may feel a little more respect.
There is a whole lawncare industry dedicated to poisoning dandelions. What a shame! The roots, leaves, and flowers of this plant are an excellent tonic and stimulator to the liver and kidneys, and the young greens are very tasty in salads. It is most important to bees in the early spring, providing them with food during a lean time before many other flowers have bloomed.
For each plant Scott covers, he provides historical information, a description, collection and habitat, medicinal uses, plant chemistry, pharmacological actions, scientific studies, and ecological importance.
Even the tamarisk has uses: In addition to salt it also concentrates and removes lead, cadmium, copper, arsenic, sodium and perchlorate from the soil. It has been used to create a natural pink or purple dye, and it also has antimicrobial properties. Some extracts can be used as a liver tonic. Carl Jung noted, “What you resist, persists.” This is, perhaps, the essence of Scott’s philosophy. By hating weeds and fighting them, we are only creating more of the same disturbed habitat that allowed them to invade in the first place. By accepting them and showing a little respect, perhaps we can help the ecology heal itself into a new diverse equilibrium.
The urban gardener’s scourge, bindweed, also has uses. The roots of this morning glory relative can be 16 feet or longer. New plants come up from every bit of cut root left in the soil, and the hard-coated seeds have been shown to remain viable for up to 60 years. Bindweed has a reputation as a purgative and a brain tonic in herbal medicine. The aboveground portions of the plant can be harvested in the summer, the roots in autumn, and both can be prepared either fresh or dried. The Ayurvedic dose is 3 to 6 grams of the powdered dried plant.
Alice Toler is a regular contributor to CATALYST.