Eco-gardening is at its best in The Monday Garden
October 30, 2005, Issue 183
POISON IVY: THE FALL VIEW
By now, I hope that all readers of The Monday Garden can recognize the summer form of poison ivy but can you also recognize the equally dangerous fall version, especially after the poison ivy leaves have fallen and mingled with the harmless oaks and maples? Never jump in a leaf pile or burn leaves (not a good idea anyway) without first checking for poison ivy. The pictures tell the story.
Picture: poison (poison oak –looking variety) on a wall, 5th Street, Stamford ct Oct 2005.
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Pictures: summer and fall view of poison ivy on a Norway maple trunk, 5th Street, Stamford CT summer and fall, 2005. Note the leaves on the right have the notched “oak leaf” form but those on the left on round-edged. View same tree in winter
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Pictures (above and below): 6 samples of fall poison ivy leaves, Stamford CT Oct 2005. Note the wide range of color from yellow-brown, to pure yellow, to orange, red, and burgundy.
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Picture: poison ivy leaves climbing a tree in the swamp at the Bartlett Arboretum and along path at the Stamford Nature Center, both pictures: Stamford CT Oct 2005
Photo credits: Sue Sweeney
© Sue Sweeney 2005
Comments (3)
Great article!
Near where I live there is a nice marsh with Poison Sumac growing in it. This small tree's leaves turn brilliant red in the fall. There is one place along the boardwalk through the marsh where a small Poison Sumac shrub grows right beside the trail. And every fall I am amused to see that someone has collected a branch with its beautiful red leaves! Oops! Most people have no idea what this shrub looks like - it's not very common and as well most people don't go where it grows.
Posted by Walter Muma | November 1, 2005 10:01 PM
Posted on November 1, 2005 22:01
You can see pciutres of poison sumac on Walter's wonderful site at http://ontariotrees.com/main/s/sumac/poison/
Sue
Posted by S. W. Sweeney | November 2, 2005 8:28 AM
Posted on November 2, 2005 08:28
Largely because I am one of the folks who still do not respond to the Poison Ivy oil, and thus still grub some up every once in a while (and wash up aftewards to protect other people), I want to add a bit about what a wonderfully sneaky plant this is. It would not be anywhere near as much of a problem if it did not do the "scandens" thing. Poison Ivy seedlings actually do have a tap root, and for the first year or so, they rise from it like some delicate shrub, but once they get comfortable, they send out horizontal shoots that grow out much faster than the vertical shoots grow up (even the ones that find something to climb do not grow so fast). These thin red horizontal shoots run right along the surface of the ground, underneath ground covers, turf thatch, and leaf litter trying to root at every leaf node. The next year, there are shoots at the nodes that root. The shoots are usually twiggy, but each one is just part of a rapidly growing network that is looking for anything to climb up towards more sun.
The best course is to find the seedling before it kicks into spread mode. For all the Poison Ivy berries the birds eat around here, they are surprisingly uncommon. Even if the plant has started to spread, remembering that it is spreading from a center can help to identify patches to try to control. I once removed a 6' wide patch behind my brother's barn and found only one deep root. If that tap root is not removed, you can be sure the Poison Ivy will be back. I think that getting the center with its tap root out substantially weakens the rest of the plant, but I have not rigorously tested that idea.
Posted by JonathanJustice | April 24, 2006 3:11 AM
Posted on April 24, 2006 03:11