Wednesday, October 8, 2008

Poison Ivy

I decided to start with the plant that seems to be most pervasive where I live, poison ivy! The scientific name for poison ivy is Toxicodendron radicans. We live on about three acres of mostly new growth woods and poison ivy is rampant! We have poison ivy creeping in our yard. We have it growing healthily over our trails. We have poison ivy bushes in the undergrowth and poison ivy vines running up the trunks of trees into the canopy where they send out branches a few feet long making dead trees sometime looks like they have returned to life!

How do I identify it? Well...everyone knows "leaves of three let them be", but we have a lot of other plants that mimic poison ivy. We have tons of box elder seedlings. I can distinguish them from poison ivy because their leaf clusters grow directly opposite each other instead of alternately like poison ivy. Virginia creeper joins poison ivy in covering our tree, but I can tell the different because mature virginia creeper has leaves in groups of five. If I see a young vine with leaves of three, and I think it might be virginia creeper, I carefully follow it to find out if it attaches to another vine with leaves of five. Also virginia creeper doesn't send out lots of hairy roots like poison ivy does. Wild strawberry has leaves of three but they have serrated edges. Poison ivy leaves may have a few serrations, but they are not serrated to the extent that the wild strawberry is. Our blackberries and rasperries have leaves of three, but they are thorny and have light colored undersides to help distinguish them.

I went out today to take some poison ivy photos. A lot of the foliage is already starting to droop from the cold weather. I had trouble getting good photos. I asked the kids if I should bring some samples inside, but they were opposed to that idea.

So have we had a lot of problems with allergic reactions to the poison ivy since we moved here? We have had some, but we have gotten better (especially the kids) at avoiding it over the last three years. I don't think Diana has had a rash yet, but she might not have been sensitized. I had my first rashes this year. (I was one of those lucky ones who wasn't sensitized previously myself.) I generally don't mind it. We warn others who visit us, and as far as we can tell a visitor has never gotten a rash. The kids get several minor rashes a summer, but as I said, less each year. If we stay here, we will probably try to reduce the amount of poison ivy, but I doubt it will ever be all gone.

A few interesting facts about poison ivy: it doesn't grow in California or Newfoundland, at very high elevations, or in the desert, but other than that it is found in most parts of North America. It is a native plant of North America and is more common now than it was in previous centuries. I likes both shade and sun and all types of soil It can grow in land that is frequently flooded with brackish water making it common even in beach areas.
1. poison ivy (Toxicodendron radicans)


Steve Ballmer said...

Good blog here!

SoundHunter said...

Hey this is cool! 100 is a lot, this will be fun. Maybe me and my oldest and I should do this too.