Does Poison Ivy Grow in Oregon? Identifying and Avoiding Rash-Causing Plants

Does Poison Ivy Grow in Oregon?

Poison ivy is a common plant found throughout many parts of the United States, including Oregon. It's important for Oregon residents to be able to identify poison ivy and understand where it grows in order to avoid coming into contact with it. Contact with poison ivy can cause an itchy and sometimes painful rash in most people.

What is Poison Ivy?

Poison ivy (Toxicodendron radicans) is a plant that can be found growing in all corners of the United States except for Hawaii, Alaska, and parts of the western states. It typically grows in the form of a vine or shrub near trees, forests, and along the edges of trails and fields.

Poison ivy gets its name from the rash it can cause in people who come into contact with it. The rash is caused by an oily resin called urushiol that is found in all parts of the poison ivy plant - the leaves, stems, and roots. Urushiol triggers an allergic reaction when it comes into contact with skin, resulting in redness, swelling, itching, and blisters.

Identifying Poison Ivy

Poison ivy can be identified by its distinctive leaf pattern. Leaves emerge from the stem in groups of three, which is where the saying "leaves of three, let it be" comes from. The leaves have pointed tips and may have smooth, toothed, or lobed edges. Leaves can be green or red depending on the time of year.

The plant may grow as a vine climbing up trees, rocks, or poles. Or it may grow as a shrub up to 4 feet tall. Older vines can get quite large with stems up to 1 foot wide. Small greenish-white or cream flowers appear in clusters in spring, followed by waxy white berries.

Where Does Poison Ivy Grow in Oregon?

Poison ivy is found throughout most of Oregon, apart from the high mountain and desert regions. It grows best in moist soils and part- to full-shade conditions. Some of the most common places to encounter poison ivy in Oregon include:

• Forests - especially along trails, streams, and forest edges
• Fields and meadows
• Backyards and gardens
• Parks
• Along fencerows or stone walls
• Disturbed areas like roadsides or construction sites

Poison ivy thrives along the banks of streams and rivers. It also does well in open forests and at the edges of woods. Backyards, parks, trails, campgrounds, and roadsides are other prime locations to find poison ivy in Oregon.

Tips for Identifying and Avoiding Poison Ivy

Here are some useful tips for identifying poison ivy and avoiding contact with it when spending time outdoors in Oregon:

• Learn how to identify the unique leaf pattern - leaves of three, each with pointed tip.
• Look for hairy aerial rootlets on the vine - these help the plant climb up surfaces.
• In spring, small green-white flowers appear in clusters.
• Berries form after flowering. They are green at first then become cream or yellowish-white.
• Avoid areas where poison ivy grows. Stay on trails and wear long pants and boots.
• After hiking or gardening, wash skin and clothes right away to remove any lingering oil.
• Use barrier creams or lotions before going into areas where poison ivy may grow.

What to Do If You Contact Poison Ivy

The best defense against poison ivy is avoiding contact with it in the first place. However, if you do brush against the plant or walk through an area where poison ivy grows, act quickly to try and prevent a rash:

• Wash any exposed skin with soap and warm water immediately to remove urushiol oil.
• Clean under fingernails thoroughly to remove any residue.
• Wash clothing, shoes, tools, backpacks, etc that may have touched poison ivy.
• Apply rubbing alcohol, degreasing dish soap, or products like Tecnu to the exposed area to dissolve urushiol.
• If a rash develops, avoid scratching as this can spread the reaction. Apply cool compresses and over-the-counter hydrocortisone cream.
• See a doctor if the rash is severe, covers a large area, or if fever or swelling develops.

Treating and Removing Poison Ivy

If poison ivy is growing in your yard or garden, carefully remove it to prevent accidental exposure. Make sure to wear gloves, long sleeves, pants, and eye protection when handling the plant. Some treatment options include:

• Cutting or mowing - repeated mowing can control growth but won't kill the plant.
• Digging up roots - use a shovel or weed puller to remove as much of the root system as possible.
• Herbicides - products with glyphosate or triclopyr can be effective when applied correctly.
• Goats - goat grazing can help control poison ivy since goats are immune to the toxic oils.
• Avoid burning poison ivy as this can cause urushiol particles to spread in smoke.

Properly disposing of poison ivy plants is also key. Wear protective clothing while handling, seal in plastic bags, and discard with household trash pickup - never in compost piles.

Other Plants That Can Cause Skin Irritation

While poison ivy, oak, and sumac are the most notorious for causing itchy rashes, there are a number of other plants found in Oregon that can irritate the skin for some people:

Stinging Nettle

Stinging nettle (Urtica dioica) is a bushy perennial plant with sharply toothed leaves covered in tiny needle-like hairs. Brushing against these hairs injects chemicals that cause stinging, itching, redness, and swelling. This plant grows in moist soils along streams, in forests, and in disturbed sites.

Bull Nettle

Bull nettle (Cnidoscolus stimulosus) is an annual native to Oregon that grows in open sunny areas. The stems and undersides of leaves are covered in stinging hairs. Contact causes burning, stinging, and blisters in some people.

Wood Nettle

Wood nettle (Laportea canadensis) is a relative of stinging nettle that grows in moist forests. The topside of leaves and stems have stinging hairs that cause pain and irritation upon contact.

Spurge Nettle

Spurge nettle (Cnidoscolus angustidens) is a native plant of the spurge family found in woodlands and thickets. The leaf undersides and stems have stinging hairs that can irritate skin.

Giant Hogweed

Giant hogweed (Heracleum mantegazzianum) is a large invasive plant with thick hollow stems and umbrella-shaped flower heads. The clear sap contains chemicals that sensitize skin to sunlight causing blistering burns and scarring.

Wild Parsnip

Wild parsnip (Pastinaca sativa) has yellow flowers resembling cultivated parsnips. The sap contains chemicals that cause the skin to react badly when exposed to UV rays, leading to burns, blisters, and discoloration.

Spurges

Some spurge plants like leafy spurge (Euphorbia esula) and cypress spurge (Euphorbia cyparissias) produce an irritating white sap when damaged that can cause skin inflammation.

Common Mullein

Common mullein (Verbascum thapsus) has woolly leaves that can be skin irritants for some people. The small

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.