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Hairy vine – No friend of mine!

Poison Ivy and Poison Oak

Nothing takes the fun out of being outdoors faster than an encounter with poison ivy. It regenerates readily, is everywhere, and people loathe it. All are perennials in the cashew family, and all cause a rash, blisters, and itch. “Leaves of three, let them be” is still the best way to identify poison ivy and poison oak. Poison ivy’s leaves are pointed. Poison oak’s leaflets are rounded. Poison Ivy’s “leaves of three” are glossy-green, but are tinged with pink in the spring, and take on a brilliant orange in the autumn. It has small, pearl-colored berries that are a favorite treat of many birds, which spread poison ivy seeds around the countryside.

The poison is an oily resin called urushiol that occupies every part of the plant, including the roots. The leaves, especially young ones, contain the most toxins. The oil can remain on tool handles and clothing for as long as a year. Dogs and cats can carry its potency on their fur. This is why you can come down with a rash without having seen poison ivy in months. Fortunately, the oils don’t always go to work immediately, especially on dirty or work-hardened hands.

Both poison ivy and poison oak grow in sun or shade, in wet or dry places, and turn vivid colors in fall. The berries are white and are a good identifier once the leaves have fallen off in early winter. Poison ivy can grow as a groundcover, a shrub, or a vine. Emerging leaves have a red tint to their edges. It grows as a vine or shrub. Both poison ivy and poison oak climb trees, sending out thick, hairy, aerial roots. Virginia creeper is often mistaken for poison ivy, but Virginia creeper has five leaflets, and blue-black berries.

Protect Yourself – If you come in contact with poison ivy, wash at once and launder your clothes using old yellow laundry soap or borax to cut the oil. (Soaps made with fat are ineffective.) For mild cases use calamine lotion, over-the-counter cortisone creams, and saltwater soaks, but severe cases require prescription cortisone. A barrier cream, IvyBlock, containing quaternium-18 bentonite, which bonds with the urushiol, promises to be effective 68%of the time, if applied before any contact with poison ivy.

Wear long sleeves, pants, closed shoes, thick gloves, and even a mask when removing poison ivy and poison oak. Ivy Block is an FDA-approved lotion that, when applied before exposure, prevents skin that comes in contact with urushiol from developing the rash. It’s available at drugstores.

Wash all clothes, even shoelaces (without touching them with your bare hands), after working near poison ivy and poison oak. Use hot water, detergent, and two wash cycles.

Wipe down any surface that has come in contact with the oil (tool handles, doorknobs, shoes, etc.).

Wash it away. Do not wipe with water. Urushiol is an oil. Rinse the affected skin with isopropyl (rubbing) alcohol, then with cold water. Don’t wipe. Wiping spreads the oil.

Burt’s Bees Poison Ivy Soap and Res-Q Ointment also remove the oil and relieve itching. Without treatment, the infected area will blister within a few hours to three days. The fluid in the blisters will not spread the rash, but any clothing that has come into contact with the oil will. Oral antihistamines can help, if needed.

Poison ivy and poison oak spread by seed and by their vigorous root systems. Birds eat the berries and deposit the seeds. If you have wooded or neglected areas surrounding your property, you probably have poison ivy as a neighbor, and given time, it will creep into your yard. Plants can be destroyed by covering them with black plastic or spraying them with the appropriate herbicides, but beware—even dead plants are infectious.

Five ways to beat this foe into submission:

1. Keep it out. Prevent poison ivy or poison oak from taking hold in the first place. If you are landscaping or tilling soil for a new bed or garden, don’t leave the ground bare for long.

2. Small infestations are more easily controlled than larger ones, because they have less-developed root systems, fewer stored food reserves in roots and rhizomes, and a smaller seed bank in the soil. Poison ivy can be readily pulled in early spring if only a few plants are involved.

3. Cut it off. As with all perennials, you must completely remove the root or the plant will resprout. Unfortunately, poison ivy roots can run underground for many feet before the plant reappears above ground. If endless digging is not appealing or an option, repeatedly cutting the plant to the ground eventually starves the root system and causes the plant to die. Plants climbing trees should be severed at the base. Don’t bother removing the vines from the tree; they don’t do any harm. The weed is just using the tree for anchorage. It’s not a parasitic relation- ship.

4. Smother it. Cover the infested area with thick black plastic sheeting, and plan to leave it there for at least a year, possibly longer. Make sure the plastic isn’t the type that degrades in the sun, and cover the edges with dirt to exclude all light.

5. Chew it up. Grazing animals, especially goats, are not bothered by urushiol and can clean up an infested area. They won’t take out the root system but will get rid of the top growth, weakening the plant overall.

Dispose of poison ivy and poison oak in plastic bags and put them out with the trash. The easiest way to do this is to put the plastic bags over your gloved hands, pull the plants into the bags, and then pull the bags inside out off your gloved hands, encasing the poison ivy inside the bag. Be nice to your garbage man and put the poison-ivy-filled bags into a larger, uncontaminated bag.

Don’t compost it. Urushiol remains potent for years—even, in dry climates, decades.

Never burn it. Breathing in smoke or soot from the plants may cause serious inflammation of respiratory mucous membranes.

Other Itchy plants are:

Myrtle spurge, or donkey tail has toxic, milky latex that can scar the skin.

Rue contains a photochemical in all parts of the plant that causes a heightened reaction to sunlight.

Spotted knapweed causes hives with repeated exposure.

The sap from the century plant will burn your skin.

Wild parsnip has a juice found in the leaves, stems, and fruits that causes photosensitization.