Nature is filled with stinky plants, but the ones below produce aromas comparable to some of the grossest odors known to humankind—think poop, cat pee, or even worse.

1. GINKGO TREE (GINKGO BILOBA): VOMIT 

Jean-Pol GRANDMONT via Wikipedia // CC BY 3.0

 
There’s a reason why the ginkgo tree has survived on Earth for at least 200 million years: The living fossil is durable, low maintenance, and resistant to diseases and pests. These qualities make it an ideal tree to plant in cities. However, planting ginkgos can be a crap shoot, as young male trees and female trees—which eventually produce seeds—look identical.

However, they're decidedly not the same. The mature female ginkgos possess a less-than-ideal feature: When they shed their fruit each fall, the fruit rot and release a foul smell that’s often likened to vomit. The fruit contain butyric acid, which also can be found in both barf and rancid butter; scientists think that long ago, this scent may have compelled dinosaurs to eat and digest the fruit, thus spreading the seeds far and wide. Adding injury to olfactory insult, ginkgo seeds’ flesh contains a chemical similar to the one found in poison ivy, meaning it can cause rashes.

2. MISSOURI GOURD (CUCURBITA FOETIDISSIMA): ARMPIT

 
Visit the central and southwest U.S., and you may encounter the Missouri gourd, a.k.a. buffalo gourd—a vine-y plant that sprouts tiny gourds that deepen from yellow-green to yellow-brown when they mature.

Judging from its Latin name (Cucurbita foetidissima, the latter part meaning “very fetid”) and its nicknames (which include “fetid gourd" and “stinky gourd”), you can probably assume that the Missouri gourd doesn’t smell great. In fact, its leaves and fruit are said to smell like a ripe armpit, and one can pick up the noxious scent simply by brushing against a leaf.

For the most part, people steer clear of the Missouri gourd. However, the Apache used its roots and crushed leaves, stems, and fruits for medicinal purposes, and its saponin—which produces suds—for soap and shampoo.

3. SKUNK CABBAGE (SYMPLOCARPUS FOETIDUS): SKUNK, PUTRID MEAT, AND GARLIC


 
According to the late naturalist Neltje Blanchan, skunk cabbage, which grows in marshy, wooded areas, swamps, and along streams throughout North America, smells like “skunk, putrid meat, and garlic." Not surprisingly, the skunk cabbage’s Latin name, Symplocarpus foetidus, means “to stink.”

Skunk cabbage owes its odor to skatole, a crystalline organic compound that occurs naturally in feces, and cadaverine, an organic compound that’s produced when amino acids decompose in rotting animals. The plant's unsavory aroma attracts insects for pollination purposes, and makes it unappealing to grazing animals.

4. JACKAL FOOD (HYDNORA AFRICANA): POOP

 
Hydnora africana (also known as jackal food or jakkalskos) is native to southern Africa, and sprouts on the roots of other plants. It's a round, parasitic flower with narrowly-spaced, threadlike structures between its sepals To attract dung beetles, which pollinate the flower, jackal food emits the smell of feces. The beetles crawl into the flower, and the sepal's threads prevent the insects from leaving easily, forcing them to stick around long enough to finish the job.

5. CALLERY PEAR (PYRUS CALLERYANA): ROTTING FISH

 
A common tree throughout North America is the Callery pear (also called Bradford pear), a tree that’s native to China and Vietnam. The Callery pear was once prized for its hardiness, ability to thrive in disparate soil and climate conditions, and beautiful white blossoms, which are among the first to bloom in springtime. Now it’s notorious for the scent of its flowers, often likened to dead fish. Plus, thanks to its capacity to grow in any environment, the tree is swiftly becoming an invasive pest that crowds out native species.

6. BOXWOOD (BUXUS SEMPERVIRENS): CAT PEE

 
If you’ve ever caught a whiff of cat pee while strolling through a formal garden, chances are a feline wasn’t responsible. You likely smelled the common boxwood, or Buxus sempervirens—a leafy green landscape shrub that’s often planted into hedges or trimmed into topiaries. Their leaves contain an oil that, when heated by the sun, smells akin to your kitty’s urine.

7. CORPSE FLOWER (AMORPHOPHALLUS TITANUM): ROTTING FLESH


 
The mother of all meat-scented flowers is the massive titan arum—more commonly known as the corpse flower—which is native to the rainforests of Sumatra, Indonesia. Titan arum takes years to bloom, and when it finally does unfurl, it stays open for only a short period of time. Be glad the bloom doesn't last longer, as the blossom emits the stench of rotting flesh to attract pollinating flies and carrion beetles. Experts don't quite know what chemicals are responsible for titan arum's stink, but they have identified the main odorants: the molecules putrescine and cadaverine.

8. TREE OF HEAVEN (AILANTHUS ALTISSIMA): SEMEN

 
A Pennsylvania gardener introduced the Tree of Heaven to American soil during the mid-18th century, and Chinese miners and railroad workers brought it with them from Asia to America when they immigrated during the Gold Rush years [PDF].

The hardy deciduous tree is tolerant to air pollution and able to thrive in harsh environments, so you’ll find it growing everywhere from urban areas to rocky areas to roadsides. However, thanks to the Tree of Heaven’s capacity to rapidly grow and spread—along with a toxin in its leaves and bark that stunts the growth of the plants around it—it’s become known as a hated invasive species that crowds out native plants. Even worse? Male trees sprout blossoms each spring that are said to smell like semen.