Thursday, January 17, 2013

Drawing Flies

On the scale of good to bad smells, rotting meat is usually listed on the bad end of the scale.  Most people are disgusted and repulsed by the smell, but many insects find the smell irresistible.  Many species of flies especially love the smells.  Some species of plants and fungi have developed adaptations that take advantage of flies' attraction to this smell.  They use the flies that are drawn to the odor to help them reproduce.  In Mid-Michigan three species that have adapted in this way are the Carrion Flower, Skunk Cabbage, and Bearded Stinkhorn.

You can follow your nose to find these plants.


I previously listed the flowers in the next photos as Carrion Flower (Smilax lasioneura).  This identification was incorrect.  This flower is actually Upright Carrion Flower (Smilax ecirrata).  Upright Carrion Flower rarely reach over 2 - 3 feet in height and lack the tendrils that are present on S. lasioneura.  Both species like a variety of habitats including forest, meadows, and stream banks.  Both species feature ball-shaped flower clusters that measure about 1.5 inches across and is green colored.  The flowers bloom during May and June in  Mid-Michigan.

Carrion Flower blooms

The plant is named after its smell and lives up to its name - it smells like a rotting animal carcass.  The first time I found this plant was by smell.  I was able to smell the plant from more than 20 foot away.  Any Carrion Flower in full bloom will usually have a swarm of small flies surrounding it.

Despite the odor, Carrion Flower plants are quite attractive.  After pollination the plant develops clusters of inedible purple-black berries.

Carrion Flower berries

Skunk Cabbage (Symplocarpus foetidus) is another native wildflower that easily found by smell.  Both the flower and leaves have a distinct odor.  But unlike the Carrion Flower which blends in with its surroundings the Skunk Cabbage is hard to miss.  It is among the earliest flowers to bloom in the spring, beginning in mid-March and continuing for two months.  The flower blooms directly on the ground and is up to six inches tall.  It has a brown to purple spathe (or hood) with green spots that covers a yellow-green spadix.

Two blooms and an emerging leaf.  The yellow-green spadix is visible inside the spathe.
 It usually flowers before its leaves emerge in the spring.  This flower generates so much heat when it blooms that it can melt snow on the ground around it.  Not only flies but beetles are attracted to the smell and the location of its flowers.

Three more flowers
The flowers take a long time to decay and can be found any month of the year.  After the flowers bloom, the plant's large cabbage-like leaves emerge and grow quickly to a size of 1 - 3 foot tall. They can easily carpet the floor of swamps and other wet woodlands.  A wetland species, the Skunk Cabbage also grows along stream banks.

A large colony of Skunk Cabbage

A closeup of the leaves

Bearded Stinkhorn (Phallus duplicatus) is a species of fungus that occurs throughout eastern North America.  Also called Skirted Stinkhorn, it is found in habitats ranging from forests to field and lawns.  The mature fruiting body is 2 - 6 inches tall and consists of an "egg" emerging from the ground and a stalk topped by a globe covered with a smelly olive green "slime".  The fungus' spores are contained within this slime and are eaten and dispersed by flies that are attracted to the smell.  Below the globe hangs a net-like beard or skirt.  The smell of this fungus is quite intense and approximates the smell of dead medium sized animal such as  a raccoon.  I have found this species only once and was able to locate it by smell from over 30 foot away in dense undergrowth.

Bearded Stinkhorn


  1. Fascinating. Now when I avoid an area in the woods due to the stench of what I believe is a dead raccoon or opossum, perhaps I will search instead and see if it might be a stinkhorn.

  2. Unfortunately, when you smell something dead, it's usually just something dead... but sometimes you get lucky.