Endangered Plant Species: They Need Our Help!

In a global analysis published in 2019, scientists from Royal Botanic Gardens, Kew, in the United Kingdom and Stockholm University in Sweden calculated that almost 600 plant species had been wiped out in the previous two-and-a-half centuries, although the true number is likely to be much higher. Many more are on the knife edge of extinction.

Most people don’t know that 40 percent of the world’s plant species are at risk of disappearing, according to a 2020 international report. In the United States, 944 plants are on the federal endangered species list, and many more have been waiting in a long line to be considered for listing or are not afforded protection due to a lack of information on their numbers and the threats that they face. In Canada, according to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), 236 vascular plants and mosses are at risk of extinction.

What is Causing Plants to Go Extinct?

The most common threat to plants is the continuing destruction of the places where they live to make way for farms, cities, suburbs, roads, and other development. To make matters worse, we have degraded their remaining habitats by suppressing the wildfires that maintain the necessary growing conditions, by introducing invasive nonnative weeds and pests, and by cutting timber, extracting minerals, and carelessly using recreational vehicles. According to the USDA Forest Service, for example, invasive species introduced from abroad have contributed to the decline of nearly half of the plants listed as endangered or threatened under the U.S. Endangered Species Act. 

Theft is another factor. Populations of cacti, carnivorous plants, and other prized species have been decimated by unscrupulous plant collectors who steal them from the wild. All of these threats are exacerbated by rapid climate change and the lack of continuous migration corridors that would allow plant species to seek more suitable habitats. 

Yet plant conservation has not generated nearly the same sense of urgency or funding that animal conservation has. Plants are safeguarded only on federal lands—unlike animals, which are protected on both public and private lands.

Endangered Plants and Flowers

Here are just a few of the plants across the United States and Canada that plant scientists are working to save from extinction.

Florida Semaphore Cactus (Consolea corallicola)

This tree-like cactus with branches held out at angles was named after the semaphore signaling system that uses flags and arms held in various positions to send messages. Cactus hobbyists were thought to have extirpated the critically imperiled species native to the Florida Keys by the late 1970s. It was rediscovered several years later but today just two populations survive. Sadly, the remaining plants are all male, so the species cannot reproduce sexually. It is also under attack by a non-native cactus moth that arrived in Florida in 1989. Perhaps the most serious threat to the remaining plants is sea level rise caused by climate disruption. 

Eastern Prairie Fringed Orchid (Platanthera leucophaea)

The fringed white petals of this exquisite native orchid once carpeted moist prairies in the eastern United States and Canada during late June and early July like a wayward blanket of snow. The plant’s intoxicating, jasmine-like fragrance lured its only pollinators, night-flying hawkmoths. 

Today, when less than 4 percent of the continent’s tallgrass prairie remains—the rest destroyed by bulldozers and plows—the orchid hangs on primarily in small, isolated habitat fragments. Because hawkmoths can no longer find them, human volunteers have been hand-pollinating the orchid for the past 30 years to save it from extinction.

Pink Coreopsis (Coreopsis rosea)

New varieties of this showy, long-blooming perennial are splashed on the pages of many nursery catalogs, but in its native habitat the species is anything but common. Pink coreopsis is extremely rare along pond shores and in swales and boggy depressions scattered on the Atlantic coastal plain in the United States. In Canada, where it is restricted to the shores of three lakes in southern Nova Scotia, it is threatened by water pollution caused by expanded mink farming and shoreline development and has been deemed endangered by COSEWIC.

Western Lily (Lilium occidentale)

The United States and Canada have a wealth of spectacular native lilies, some of which are now exceedingly rare. 

Hummingbirds love the western lily’s striking flowers with red petals that curve strongly backward and spotted greenish yellow centers. So do lily growers, who have dug up the plant from the wild for commercial trade since at least the 1930s. Found only within a narrow, 200-mile stretch of Pacific coastline between southern Oregon and northern California, this endangered wildflower is declining rapidly due to continued poaching as well as cranberry farming and the draining of wetlands. 

Lake Louise Arnica (Arnica louiseana)

This dainty member of the sunflower family is one of 109 plants that grow in Canada and nowhere else in the world. Although it may look delicate, the petite perennial wildflower with nodding bright yellow blooms endures the frigid temperatures and fierce winds of its native habitat—high-elevation alpine meadows and rocky slopes in the Canadian Rockies along the border between Alberta and British Columbia. However, like many so-called endemic species with small populations and very restricted ranges, Lake Louise arnica is vulnerable to extinction by a variety of causes, including climate change.

Smooth Coneflower (Echinacea laevigata)

The sunny forest openings with calcium and magnesium-rich soils preferred by this close relative of the familiar purple coneflower that graces countless gardens were once scattered throughout the southeastern United States.

Wildfires and large grazers like bison prevented trees from colonizing these sunny habitats. But agriculture, development, and fire suppression have destroyed many of its former haunts, and collectors attracted by the coneflower’s elegantly drooping pale pink or lavender petals have depleted remaining populations. After 30 years on the U.S. endangered species list, in July 2022, the smooth coneflower was “upgraded” to “threatened.” Today, it survives precariously in utility rights-of-way and along sunny roadsides.

Dwarf Lake Iris (Iris lacustris)

This close relative of the native crested iris more familiar to gardeners is found only in the Great Lakes region. Within this restricted geographical range, it grows in the cool, moist, lakeshore air, hugging the coasts of Lake Huron and Lake Michigan on both sides of the U.S.–Canada border. 

The striking white, deep purple, and orange markings on the outer petals of this lovely low grower guide bees to the center of the flower for pollination. Increasingly rare, the dwarf lake iris is threatened largely by habitat loss caused by shoreline development.

Venus Flytrap (Dionaea muscipula)

Like pitcher plants and other species that live in nutrient-poor habitats, the Venus flytrap supplements its diet by eating meat. When hapless insects land, they stimulate hairlike projections called trichomes that cause the plant’s traps to snap shut. Digestion takes 5 to 12 days. The Venus flytrap has a very restricted range in coastal North and South Carolina. Over the years, populations of this carnivorous plant have been decimated by poachers. Today, it is also imperiled by development and fire suppression, which enable trees and shrubs to invade and degrade its habitat. Learn more about carnivorous plants.

How Can We Help Endangered Plants?

Given the paucity of safeguards and funding for the cause, gardeners can play a critical role in protecting imperiled plant species and ensuring that others do not suffer the same fate. For example, by donating funds or volunteering time—or both—you can provide muchneeded support for botanical gardens and conservation groups working to save plants in their native habitats.

Just as important, you can engage in plant conservation in your own backyard: Avoid planting the non-native invasive species that are degrading plant habitats. Plant scientists advise against attempting to grow imperiled species—unless varieties are already commonly available in the nursery trade—because populations of imperiled species are fragile and vulnerable to poaching.

Grow native plants that are not of conservation concern; this has multiple benefits. These plants provide food and shelter for birds and other wildlife. What’s more, a 2019 report by German scientists noted that most of the 355 plant species that they had surveyed in the northeastern region of that country had suffered “significant losses” during the previous two decades. Surprisingly, it was the plants that they deemed “moderately common” that had experienced the greatest declines. By gardening with plants that are native to your area, you can prevent declining common species from suffering the same fate as those clinging precariously to life.