Wednesday, May 22, 2013
Poison Ivy Likes the Rain
This Poison Ivy leaf has just filled out and by the way the raindrops are rolling off its surface, it also has the oil present that causes us humans problems.
An oil on the surface of all parts of this plant is what many people are allergic to, and contact with the oil causes the familiar skin irritation. It also causes these water drops to just roll off the leaf.
Poison Ivy's irritant is also anaphylactic to us humans, which means you can touch it every day for 20 years and have no reaction and then touch it another day and have a severe reaction.
So here it is. Each leaf stem has three
leaf-lets. Which is where the rhyme comes from..."leaves of three...leave it be."
Poison Ivy is technically a shrub, and in more southern areas it grows taller and also grows as a large hairy vine covering the trunks of tall trees.
As a boy I learned to avoid climbing those trees, unless there was something very interesting in the top of the tree.