Leaves of Three, Let It Be: The Poison Ivy Pest


Depsite the prevalence of poison ivy on Long Island, many residents don't know the proper techniques for handling and removing the pest.

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“Leaves of three, let it be.”

That’s the age old saying children on Long Island either take to heart, or learn the hard way by spending weeks applying calamine lotion to a painfully itchy rash.  Toxicodendron radicans, otherwise known as poison ivy, is definitely considered a major pest, cropping up in nearly all landscapes and leaving the unfortunate and uninformed with an itchy skin irritation that can last up to two weeks.  But is that six-word rhyme all you need to know to keep yourself poison ivy free?  Probably not.
Poison ivy can be quite tricky.  The plant can be most easily identified by the shiny, three-part leaves that range from green to bright red.  But not all poison ivy look alike.  Some plants have smooth and shiny leaves, others have a dull and textured appearance.  The plant can grow as a trailing or climbing vine or as a low-growing bush.  The leaves are oppositely arranged, and the three leaflets (the “leaves of three”) can grow between two and four inches long.  In a dark forest, you might encounter a thick vine with furry shoots growing off it in all directions without a single three-some of leaves to suggest the identity of the plant.  These vines, which can grow quite large, send out lateral branches for support whose size makes them easily confused for benign tree limbs.  The picture below shows a thick poison ivy vine (compare with the size 8 women’s boot) with hair-like shoots growing up the entire length.
Poison ivy grows throughout much of North America, and if you spend any time in the forested areas of Long Island, you know that poison ivy is especially prevalent in our region.  The plant forms a major part of the herbaceous diet of large grazing animals, such as the white-tailed deer, which was once far more common on Long Island.  As human populations strangle natural woodlands and reduce habitats for the deer, poison ivy has flourished.  Although poison ivy enjoys wooded areas, as a pioneer plant it grows equally well in rocky and sandy areas. It is especially drawn to the edge of the forest, which is why it is so common growing along fences and sidewalks, and in areas that have just been cleared of vegetation.
During the spring and summer months, the volatile oil found in the sap, urushiol, is present in all parts of the plant.  Many people believe that contact dermatitis, the medical name for the reaction caused by the urushiol, can only be a result of contact with the leaves.  But that is entirely false.  Even when the poison ivy plant has no leaves, contact with the stem or any part of the plant can cause the same reaction.
What do you do if you’ve touched poison ivy?
There are specially made soaps that should be used on all surfaces that have come into contact with poison ivy, including clothing, toys, pets, and bare skin.  People have been known to suffer an allergic reaction to the poison ivy oils from their pets fur, or from their own clothing after coming into contact with poison ivy.  If you do not have a special soap, the next best option is dish detergent since it can help break down the oil and wash it from you skin before a reaction takes place.  
How do you safely remove poison ivy?  
For starters, let’s review what you shouldn’t do to get rid of this herbaceous pest.  
1. Do not dig it up.  Poison ivy has an extensive root system, and the handling of any part of the plant, roots included, is hazardous.  
2.  Do not attempt to burn the plant.  Smoke from a burning poison ivy plant can carry traces of the urushiol, enough to still cause a serious reaction.  And, because it is airborne, the toxic chemical can easily make its way into your mouth, nose, throat and lungs.
The safest and most effective way of being rid of poison ivy is the use of chemical controls.  Be sure to dress appropriately since application of the herbicides requires the applicator be in close proximity to the plant.  Familiarize yourself with the impact of the herbicide on your vegetable and flower gardens because it can easily destroy other plants that are growing nearby.  Even after you have applied the herbicide and the plant appears dead, do not attempt to remove it.  It is best to let the poison ivy decompose since contact with the dead plant can still cause severe irritations.  Long Island has several lawn and yard care businesses that specialize in the removal of poison ivy.  The safest alternative is always to hire an expert who can recognize the many faces of poison ivy and has extensive experience in handling the plant.  
Poison Ivy can be completely harmless if you take the necessary precautions to avoid it.  That includes remaining on wide, cleared paths at local parks and not trailing off into the forest.  If you’ve recently cleared land, or are planning to, consider contacting a poison ivy control expert to preempt any growth of the plant.  Don’t touch any vines growing in the woods if you are not completely familiar with the species.  Monitor the edges of your own backyard before you send your kids outside to play.  Poison ivy doesn’t have to get you down during the warm seasons, and if you stay informed about all the hazards of this pesky plant the odds are you won’t have to be rushing to the drug store to pick up a family sized bottle of Benadryl and calamine lotion.
If you have any poison ivy stories or advice, share them in our Long Island Lounge forum discussion on Backyard Gardening.