The logic of eating wild plants is obvious; the logic of eating invasive wild plants is even more so. Culling aggressive species that have a negative impact on native plants, while avoiding the environmental pitfalls of agriculture? And free, local and abundant? Yes, please.
Invasive plants are non-native species that can thrive in areas beyond their natural range of dispersal. These plants are characteristically adaptable, aggressive, and have a high reproductive capacity. Their vigor combined with a lack of natural enemies often leads to outbreak populations — they can take on horror movie proportions.
According to the Land Management Bureau, millions of acres of once-healthy, productive rangelands, forestlands and riparian areas have been overrun by noxious or invasive plants. They destroy wildlife habitat, displace many threatened and endangered species, reduce plant and animal diversity because weed monocultures overrun all other plant species in an area, and disrupt waterfowl and neo-tropical migratory bird flight patterns and nesting habitats — to name just a few of the nuisances they create.
So what can we do? Get eating!
1. Purslane (Portulaca oleracea)
Native range: Old World, probably Southeast Asian in origin
Invasive range: Throughout North America
Habitat: Rocky bluffs, barnyards, gardens, sidewalk cracks, disturbed areas; widely found in city lots.
Because of it is a prolific producer of seeds, common purslane (pictured above) can rapidly take over warm, moist sites. And although it may not be as threatening as some of the other invasive species listed here — more of a pesky (albeit gourmet) weed — it’s included because it’s a particularly rampant plant which contains loads of omega-3 fatty acids, as well as being a great source of vitamins A and C.
The profuse succulent has thick round leaves, and small yellow flowers that bloom from midsummer to early fall — it’s kind of crunchy, and tastes both tangy and a bit salty.
2. Japanese Knotweed (Polygonum cuspidatum)
Native range: Japan, China and Korea
Invasive range: Throughout North America and Europe
Habitat: Riverbanks and roadsides, agricultural areas
Introduced as an ornamental and for erosion control, this aggressive perennial can reach 6 or 7 feet in height and is all too happy to push out native species. It mostly spreads through rhizomes, with shoots so hearty they break through asphalt and can survive underground for years. Many a frustrated gardener has discovered this species to be nearly indestructible.
The pretty leaves are alternate, egg shaped; stems are hollow. Small white flowers bloom in late summer. The fruit is a single seed within a three-winged calyx.
3. Dandelion (Taraxacum officinale)
Native range: Eurasia
Invasive range: Throughout North America
Habitat: Public and private gardens and lawns, roadsides, sidewalks, degraded meadows, rocky hillsides, forest openings
Some of us (me) may love the earnest dandelion, but many see the plant as an invasive weed that does little more than sully an otherwise perfectly-manicured lawn. It’s believed that dandelion was first brought to North America by the Pilgrims on the Mayflower for its medicinal uses. A single dandelion produces around 2000 seeds per season, giving the weed great potential for broad dispersal, and its non-native status means that is can displace its native relatives.
It has been shown that dandelion can pose a threat to alpine zones and upper forests through competition with conifer seedlings. On the other hand, dandelions easily colonize disturbed and over-grazed habitats, and can serve as an important source of grazing for cattle, wild ungulates, and bears.
The pervasive root systems of dandelions make eliminating them very tricky without thorough and repeated applications of cultural, mechanical or chemical control, making them a bane to gardeners (and a boon to eaters).
4. Kudzu (Pueraria montana)
Native range: Asia
Invasive range: Throughout most of the Southeast, and as far north as North Dakota.
Habitat: Roadway, edge of forests, home gardens, everywhere.
It's been said that you can actually watch kudzu grow — and given that it can grow up to a foot a day in the proper conditions, it might just be true. Kudzu was first brought to the U.S. by Japan for the 1876 Centennial Exposition in Philadelphia. By 1900, its fragrant purple flowers and the vine’s miraculously quick coverage ability made it a popular choice for porches across the Southeastern US…it now covers more than 7 million acres in the south east.
The insatiable vine will take over anything in its way — other plants, buildings, road signs, you name it. It kills other plants by blocking light, as well, it strangles stems and tree trunks, breaks branches, and uproots trees and shrubs. Eat, eat, eat!
5. Curly Dock (Rumex crispus)
Native range: Europe and North Africa
Invasive range: All 50 states
Habitat: Common in fields, roadways, gardens, yards, disturbed areas, glades, meadows, and along streams and riverbanks
Curly dock is a highly aggressive plant that spreads by seeds through self-pollination — the non-native plant is found in agricultural landscapes throughout the U.S. and listed as invasive in 15 states. Curly dock grows very large at times and can block out sunlight to other plants in the surrounding areas. It can also out-compete them for soil nutrients and water.
Curly dock is a relative of rhubarb in the buckwheat family, and is also known as sour or yellow dock. It's high in oxalic acid, and may be irritating to sensitive skin, and should only be used raw in moderation. Use it when the leaves are young, and it can be boiled in several changes of water. That said, it's delicious.