Jewelweeds Help Each Other

Some plants are known to reduce their uptake of nutrients when growing close to others of their species, helping the other plant to thrive.  Now our common jewelweed (Impatiens pallida) has been found to do the same thing above ground.  A study from McMaster University in Ontario reports that its usually short leafy stalks are present when growing close to other species.  When growing close to other jewelweed, "it grows taller stalks with fewer leaves, thus sharing the sunlight".  The story is reported in this months Smithsonian Magazine.

This is just another fascinating aspect of this common Missouri flower.  Also known as the pale touch-me-not
Impatiens pallida is distinguished from its cousin Impatiens capensis pictured below by its pale yellow flowers and the spur that points downward at right angle to the flower. 

Jewelweed frequently is found growing close to stinging nettle in low moist woods, thickets and along streams.  Their close proximity may be how Native Americans discovered that the jewelweed juice soothes the burning skin caused by coming in contact with the stinging nettle's hairs.  
Many cultures felt that plants with medicinal properties grow next to toxic plants. The gumbolimbo tree whose sap is used to treat sunburn as well as the poison ivy-like burning from contact with its neighboring black poison wood tree.  In Belize, the gumbolimbo tree is also called the tourist tree as it has a red trunk with thin white strips of bark that look like a sunburned tourist.  You have to love a tree named gumbolimbo.
A more entertaining characteristic of jewelweed is found in the seed pod.  When ripe, they seem to literally explode as the pod springs open, throwing the seeds out several feet. More details about this plant with pictures of the seed pods can be found on this page of  Missouriplants.com.