1) The problem: what invasives are, botanically and culturally
Weeds are plants that grow where we don’t want them to, and invasives are weeds we spread without control, altering ecosystems to such an extent that, sometimes, native species are crowded out and go extinct.
Invasives are expressions of our colonial culture; we bring them—and cats, rats, carp and pigeons—with us as we transform biomes to suit our desires.
Consider how agriculture—the growing of the most innocent flower or vegetable garden—involves the favoring of certain species and the annihilation of others. Belying its image as a peaceful pursuit, gardening requires a lot of deep-seated prejudice, kneejerk discrimination and cold-hearted killing. Every idyllic field of corn is the result of a farmer’s successful war against other plants, and against fungus, insects, birds and mammals.
Corn is a wonderful food, and plant that cannot self-seed. It requires humans to clear ground for it, and to plant and feed and raise it to maturity. This makes it the perfect example of a non-native plant we have no qualms about going to war for. We don’t mind invading native ecosystems and killing the native species that live there, and then planting corn there. Corn is an invasive species—95 percent of the total feed grain production in the USA is corn—despite the fact that it cannot spread itself like a pandemic without us, the invaders, heirs to 500 years of Euro-American colonial culture and behavior.
Here’s the River Kelvin in Glasgow, Scotland, downstream from the Botanical Gardens—
The yellowish plants draped over the river are Japanese Knotweed, and there is little doubt that they are there because their ancestors lived in the Botanical Garden and escaped.
We don’t think of corn as an invasive plant species because we don’t consider it a weed. When we think of invasives, we think of knotweed, multiflora rose, asian bittersweet. We think of dandelions and thistles and creeping charlie. We think of tumbleweed and garlic mustard and dock and purple loosestrife. We think of plants that got out of control after our ancestors collected, transported and planted them, altering and redesigning ecosystems to suit their own selfish desires, not ours.
Here’s an invasive, fig buttercup, that crawled into my lawn about three years ago.
I let it flourish because it’s sort of pretty and blooms in the early spring, before most other plants. It has tuberous roots, though, and reproduces by rhizome—and excretes a toxin that offends other plants. It is a very successful invader. This spring I will begin to remove it before it spreads even more.
We have deep-seated prejudices against invasives because they are “slaves” that liberated themselves from us, who thought we were their “masters.” Their overtaking of our landscapes is, to us, a rebuke and, perhaps worse, constant proof that we are not very wise in the ways of inhabiting our biomes.
How many times have we driven down superhighways and seen mile after mile of forests cloaked by asian bittersweet?
How many times have we left a corner of the yard uncut for a few months and noticed pricker bushes growing there?
What if, instead of multiflora rose growing there you saw invasives you want because they feed you, and the birds and whatever else wants to eat it?
2) the solution: the “milpa” concept of edible landscapes, and its history in middle CT River valley
In his fascinating history of ancient Mesoamerica entitled 1491, Amherst author Charles Mann defines what a milpa is:
A milpa is a field, usually but not always recently cleared, in which farmers plant a dozen crops at once including maize, avocados, multiple varieties of squash and bean, melon, tomatoes, chilis, sweet potato, jícama, amaranth, and mucana…. Milpa crops are nutritionally and environmentally complementary. Maize lacks the amino acids lysine and tryptophan, which the body needs to make proteins and niacin;…. Beans have both lysine and tryptophan…. Squashes, for their part, provide an array of vitamins; avocados, fats. The milpa, in the estimation of H. Garrison Wilkes, a maize researcher at the University of Massachusetts in Boston, “is one of the most successful human inventions ever created.”
A great introduction to milpa-style forest gardening was co-written by Eric Toensmiller who lives in Holyoke, and here is a picture I’ve copied from it that shows you how simple it can be; basically all you have to do is kill your lawn and replace it with food and materials producing trees and plants:
Here are pictures of the remains of the Nonotuck people’s “slash-and-burn” version of milpa gardening: three-sister (corn, bean, squash) mounds. You have to remember they were growing at the edge of food-forests that included the American Chestnut tree which probably fed more mammals than any other plant species:
It’s too late now, in many places, to prevent the spread of invasives anymore than it is possible to prevent the spread of us. What we can do, though, is manage our own gardens and forests with a permaculture ethic that reduces our own invasive behaviors. If there are no native places left around us due to our colonial history, what we still have is a living ecological system that sustains us. Understanding that system is key to effectively managing it.
One of the tragic ironies, worth reviewing before we move on to selecting the best food-producing invasives, is that the industrial production of Monsanto GMO Round-Up Ready Terminator-Seed corn crops has generated Round-Up resistant superbugs and superweeds. Agro-industrial production of this kind is already proving to be an evolutionary failure.
One of the superweeds that Monsanto has created, yet has no interest in patenting, is “pigweed”:
Pigweed is of the amaranth family, that “is thought to have represented up to 80% of [Aztec] energy consumption before the Spanish conquest.”
It is, in fact, a superfood! According to “a 1993 study by the Institute of Nutrition of Central America and Panama at Guatemala: “Using cheese protein as a reference, researchers concluded that the protein in amaranth ‘is among the highest in nutritive quality of vegetable origin and close to those of animal origin products.'”
If we stopped spraying it, and spent a few USDA research dollars “improving” it by increasing its leaf- and seed- sizes, it could feed us all.
As long as we consider “pigweed” to be an invasive, however, it will continue to take over our agro-industrial fields and our GMO farmers will spray larger quantities of more lethal poisons into our increasingly imperiled corporatized food-system. Our toxic culture is reaching an evolutionary dead-end, and nothing more than a cultural transformation will help us circumvent it:
The concept of milpa is a sociocultural construct rather than simply a system of agriculture. It involves complex interactions and relationships between farmers, as well as distinct personal relationships with both the crops and land. For example, it has been noted that “the making of milpa is the central, most sacred act, one which binds together the family, the community, the universe…[it] forms the core institution of Indian society in Mesoamerica and its religious and social importance often appear to exceed its nutritional and economic importance.”
3) “native” invasive species that can be used in your edible landscape
As we’ve learned, the Nonotucks imported non-native food-plants (corn, beans, squash that originated in what is now central Mexico)—which unsettles the definition of “native” itself. Until at 12,000 years ago when the Laurentian Ice Sheet retreated northward, there were no human beings or any other life forms (except bacteria)living in what is now the middle Ct River valley.
Humans are invasives and bring invasives with them that they use to transform biomes to suit their desires and cultural values. As we enter the Anthropocene Era of rapid climate change, we need to surround ourselves with plant species that will help us survive as our industrial economy, with its fossil-fuel- and toxic-chemical- input-dependent “economy of scale,” falters and collapses. I am hoping that by preserving what we can of our native living-systems, and to them adding “invasive” or “non-native” food species, we might nurture a resilient and vibrant post-industrial milpa-culture.
Here are a few native and non-native invasive species that I cultivate and appreciate. They are here as a beginning again, another start, a small gesture of creating a self-sustaining edible town:
Kiwi—a “non-native” food-producing monster that must be planted in a spot where is can ruthlessly pruned and mowed down, as it grows in any direction it can:
After 5 years, this monster produces more fruit than I can even pick, and the fruit tastes better than any I’ve ever purchased. I have to hack it constantly or else it will consume the apple tree (right side).
Pawpaw—a “native” fruit tree that likes to live in warm, partly shady, conditions; we live at the northern edge of its habitat. The yellow flame you see is a single tree that, via rhizomes, has become a grove, almost a small forest:
The Pawpaw fruit must be picked and eaten before it gets too ripe, or else it is insipid. It tastes like a cross of mango, banana, strawberry and cream:
Wineberry—a non-native that spreads like wildfire, so it needs to be cultivated in a spot that can be mowed.
Its fruit is sour and sweet, and seems to resist the fruit flies that have destroyed our other non-native raspberries:
Wild blackberries are native. Our only native raspberry is Rubus Odoratus:
Black Locust—a native that is considered invasive because it spreads by rhizome rapidly colonizing fields and lawns; its wood is “yankee teak”: hard and rot resistant, the best choice for fenceposts. It has the highest btu pf local firewood, and burns long and slow in the woodstove. Its flowers are voluminous and beloved by honeybees, an invasive species: