Wicked Plants: The Weed That Killed Lincoln's Mother and Other Botanical Atrocities - Amy Stewart (2009)

SOCIAL MISFITS

The way some plants behave is disgusting and downright embarrassing. There are the arsonists—plants that use fire as a weapon to clear the way for their offspring and kill off their competition. Some even require a good hot fire for their seeds to germinate. Some cities in drought-prone areas even publish lists of flammable plants to avoid.

Other offenders stink, slobber, and even bleed. Don’t invite any of these horticultural misfits to your next garden party.

image

Pyromaniacs

GAS PLANT OR BURNING BUSH

Dictamnus albus

   

A flowering perennial native to Europe and parts of Africa. On a hot summer night, the plant produces enough volatile oil that lighting a match nearby can set it on fire.

EUCALYPTUS TREES

Eucalyptus spp.

   

Native to Australia but naturalized in California; the highly volatile oil produced by the trees helped spread the deadly Oakland fire that killed twenty-five people and destroyed thousands of homes.

PAMPAS GRASS

Cortaderia selloana

   

A South American native that has become a much-hated invasive plant in the western United States. Each clump can reach over ten feet tall and produce so much dry, brittle biomass that it can accelerate and redirect wildfires.

On a hot summer night, the gas plant produces enough volatile oil that lighting a match nearby can set it on fire.

CHAMISE

Adenostoma fasciculatum

   

A flowering chaparral shrub that produces a flammable resin; the plant is also rejuvenated by fire and is one of the first plants to sprout out of the blackened earth.

Stinkers

CORPSE FLOWER OR TITAN ARUM

Amorphophallus titanium

   

Resembles an enormous burgundy calla lily. It usually goes several years without blooming, but when it does, it produces a single flowering stalk that can reach up to ten feet tall and weigh over a hundred pounds. When a corpse flower blooms in a botanical garden, visitors line up to see it, but they are warned to enter the conservatory carefully as the stink can be overpowering.

RAFFLESIA

Rafflesia arnoldii

   

Produces the largest single flower in the world at over forty inches across. (The enormous corpse flower is actually a cluster of many small flowers on a stalk, knocking it out of the running.) This squatty, speckled, orange plant parasite is truly a flower that only a botanist could love. The flowers last only a few days and stink of rotting meat while they bloom, attracting flies that feed off dead animals in the Indonesian jungle where it lives.

The flowers last only a few days and stink of rotting meat while they bloom, attracting flies that feed off dead animals in the Indonesian jungle.

WHITE PLUMED GREVILLEA

Grevillea leucopteris

   

An Australian plant in the protea family that produces gorgeous stalks of yellowish white blooms. Unfortunately, most people won’t go near it because of the stink, which is reminiscent of smelly old socks.

STINKING IRIS

Iris foetidissima

   

A lovely English woodland iris whose purple and white blossoms fill the air with the scent of roast beef. Some gardeners believe it more closely resembles burning rubber, garlic, or raw meat gone bad.

STINKING HELLEBORE

Helleborus foetidus

   

Popular in England for its lime green flowers and dark, dramatic foliage. When crushed, the leaves give off an odor that has been described as “catty” or “skunky” or simply “acrid and unpleasant.”

SKUNK CABBAGE

Symplocarpus foetidus

   

Grows in wetlands throughout eastern North America and in parts of Asia. Known for its ability to give off heat; in winter, skunk cabbage can break through frozen ground and melt the snow around it, allowing it to bloom and attract pollinators ahead of spring flowers. Crushed skunk cabbage leaves give off an unpleasant scent similar to a skunk’s spray.

VOODOO LILY

Dracunculus vulgaris

   

Popular among gardeners despite its rotting meat scent. The flowers, which bloom every spring, resemble purplish black calla lilies. The plant grows to three feet tall, making it a striking feature in the garden. Fortunately, the flowers only stink for a few days while they are in full bloom.

STINKING BENJAMIN

Trillium erectum

   

A lovely red or purple trillium that thrives in moist woodland conditions in eastern North America. This is one of the milder stinking plants—botanists have described it as having a musky scent or smelling like a wet dog.

Just Disgusting

SLOBBER WEED

Pilocarpus pennatifolius

   

Actually, you’re the one who will drool. The 1898 King’s American Dispensatory reported on the plant’s powerful effect on the salivary glands, stating that “the secretion of saliva increases to such an extent as to greatly embarrass speech, the person being often obliged to assume an inclined position that the escape of the saliva may be facilitated. During its salivary action one or two pints of saliva, and even more, may be secreted.”

Don’t try this as a party trick, however. The drooling is often followed by hours of nausea, dizziness, and other unpleasant symptoms. Other plants that make you drool include the betel nut, which produces bright red saliva, as well as the Calabar bean and pencil tree, both of which also bring on unpleasant and sometimes fatal side effects.

SANGRE DE DRAGO

Croton lechleri

   

A shrub in the Euphoribiaceae family that oozes a thick red sap. The “blood” is used by some Amazon tribes to stop bleeding and treat other medical ailments.

PTEROCARPUS TREE

Pterocarpus erinaceus

   

Secretes a dark red resin that is used as a dye. The wood can be used to produce fine wood products; its leaves make good feed for cattle; and it may have some medicinal qualities.

DRACO

Daemonorops draco

   

Grows in southeast Asia; the reddish brown resin it excretes has been collected and sold in small, solid chunks as “red rock opium.” Poison control centers and law enforcement agencies in the United States started seeing the substance on the streets in the late 1990s. However, laboratory tests confirmed that it has no hallucinogenic properties and certainly contains no opium.

During slobber weed’s salivary action one or two pints of saliva, and even more, may be secreted.

image

PAINFUL

Whistling Thorn Acacia

ACACIA DREPANOLOBIUM

One of the most wicked of the hundreds of acacias found throughout the world, this scrubby East African tree employs painful, three-inch thorns to keep browsers away from its lacy leaves. It is also host to a band of aggressive, stinging ants.

FAMILY:
Fabaceae or Leguminosae

HABITAT:
Dry tropics, Kenya

NATIVE TO:
Africa

COMMON NAME:
Whistling thorn

Four different species of ants have taken up residence in these trees, although they can’t occupy the same tree without going to war with each other. They live in the swollen bases of acacia thorns, which they enter by chewing a hole through the thorn. That small hole creates the strange whistling sound that the tree makes in the wind.

The ants are not only ferocious; they’re organized, too. Small militias patrol the branches looking for predators. They will swarm over a giraffe or other grazing animal to keep it from destroying their home. Other ants selectively prune the tree, allowing new growth only near their colonies so that they can enjoy the tree’s nectar. The ants will also chew climbing vines and other invasive plants down to stumps. If a tree occupied by a rival colony stretches its branches too close, the ants will decimate half of their own tree to keep the canopies from touching and creating a bridge to enemy territory.

The little zombies carry the acacia seeds around as if they were their own dead, helping to disperse the seeds and start the next generation.

And when the tribes do fight, they fight to the death. Researchers once tied the branches of neighboring trees together to provoke a conflict, and the ant corpses were piled a half-inch deep on the ground the next morning.

Meet the Relatives     Some species, including Acacia verticillata, secrete a chemical that induces necrophoresis, or corpse-carrying behavior, in ants. The little zombies carry the acacia seeds around as if they were their own dead, helping to disperse the seeds and start the next generation. Many also have thorns; the cat claw acacia, A. greggii, is sometimes called the wait-a-minute bush because its prickles will grab hold of a hiker and refuse to let go.