Guide to Poisonous Plants and Irritants in Arkansas' Forests and Gardens

Be Wary of These Poisonous Plants in Arkansas

Arkansas' forests, fields, and backyards host a variety of plants with the potential to cause reactions and injury. Familiarizing yourself with the most common poisonous plants and their identifying features will help you steer clear of accidental exposure when adventuring or gardening in The Natural State.

Poison Ivy

Perhaps the most infamous is poison ivy. This plant contains urushiol oil that causes an itchy, blistering rash in most people. Poison ivy grows as a vine or groundcover with three pointed, smooth-edged leaflets. Leaves can be reddish in spring then green in summer, turning red and orange in fall. Rashes develop 12-48 hours after exposure and last 2-3 weeks. Calamine lotion and antihistamines provide relief while the reaction runs its course.

Poison Oak

Closely related is poison oak, which also contains urushiol. It has leaves of three leaflets like poison ivy. But poison oak's leaves are deeply lobed with a more rounded shape and notable veins compared to poison ivy's smoother edged leaves. Poison oak can take the form of a shrub or vine and develops white berries through summer. Reactions cause similar itchy rashes.

Poison Sumac

Poison sumac is a shrub or small tree reaching up to 20 feet tall in boggy soils. Compound leaves have 7-13 smooth edged leaflets arranged in pairs with one at the end. White berries in drooping clusters turn gray in winter. Again, urushiol causes rashes but poison sumac reactions can be more severe.

Stinging Nettle

This green perennial has sharp hairs on its stems and leaves that release chemicals inducing a stinging, burning sensation. Leaves are oval with toothed edges, arranged oppositely on square stems. Small green flowers give way to small brown seeds. Rubbing the rash with nettle leaves or dandelion, mint, or sage can relieve the sting.

Bull Nettle

Similar to stinging nettle but only growing up to 2 feet tall. The single, tube-shaped yellow-green flowers have stinging hairs. Leaves are egg-shaped with pointy tips in pairs along the stem. Reactions cause swelling and hives in sensitive individuals.

Cow Itch Vine

Also called velvet bean, this trailing vine has three-parted leaves and purple flowers. Be careful of the brown, furry seed pods whose tiny hairs contain chemicals that irritate the skin, often severely. It grows in southern Arkansas as a popular decorative vine for arbors.

Spurges

This diverse genus has over 200 species in Arkansas. The popular garden plant snow-on-the-mountain or variegated spurge can cause a rash when the milky sap inside the stem and leaves touches skin. The woodland spurges false loosestrife and cypress spurge also contain skin-irritating latex and grow in wooded areas.

Toxic Plants in Arkansas

Some plants in Arkansas contain poisonous compounds that can cause more toxic reactions if ingested, causing issues ranging from mouth irritation to organ damage.

Water Hemlock

A highly poisonous flowering plant found statewide, usually in wet areas. Stems are stout, smooth, and hollow with purple streaking.Compound umbels of small white flowers sit atop stems reaching 6 feet tall. All plant parts contain the toxic compound cicutoxin.

Poison Hemlock

This introduced species has fern-like, lacy leaves and white flower clusters. The stems are smooth, hollow and spotted purple. Poison hemlock contains toxic piperidine alkaloids that can induce respiratory paralysis and death if eaten.

Jimsonweed

Also called thorn apple, this weed has trumpet shaped white flowers and prickly seed pods. Leaves are oval with toothed edges, releasing an unpleasant odor when crushed. All parts contain tropane alkaloids causing delirium, confusion, rapid heart rate and possibly coma.

Pokeweed

A large perennial herb with bright purple-red berries on red stems. Leaves are oval with pointed tips. The root contains the most toxins, but all plant parts can cause vomiting, diarrhea, low blood pressure and convulsions.

Castor Bean

Castor beans are seeds from the decorative castor oil plant, which is sometimes grown in gardens. They contain the deadly toxin ricin with no antidote. Just 1-3 beans can be lethal if ingested. Keep away from children.

Lantana

This shrub with small, colorful clustered flowers is a popular landscaping plant. Green unripe berries contain the toxin lantadene. Eating them causes stomach issues. Ripe black berries are less toxic.

Rhododendrons

Available in garden centers, these woody shrubs have large, showy flower clusters. All plant parts contain toxins called grayanotoxins that can cause vomiting, dizziness, weakness and heart issues if eaten.

Skin Irritants

Some Arkansas plants won't cause major illness but can irritate skin on contact, especially in sensitive individuals. Here are some to know:

Wood Nettle

Similar looking to stinging nettle but larger, growing in partial shade. The leaves and stems have stinging hairs producing a rash when touched. Leaf edges are more rounded with deeper serrations.

Devil's Walking Stick

A small tree with compound leaves having 11-41 pointed leaflets. The bark is prickly and touching the plant causes skin redness, swelling and blistering in some.

Camphorweed

Also called pluchea, this aromatic weed has leaves with strong camphor scent when crushed. Contact dermatitis reactions occur in sensitive individuals after touching.

Parsnip

Wild and cultivated varieties of this flowering plant contain compounds called furanocoumarins that can cause skin irritation and burns when contacted in the presence of sunlight.

Preventing Poisonous Plant Injury

Avoiding contact is the best way to prevent reactions to poisonous plants. Here are some tips when adventuring or gardening in Arkansas:

• Learn to identify problematic plants in your area.
• Wear long sleeves, pants, boots and gloves in wooded, overgrown areas.
• Wash skin and clothing after exposure to suspicious plants.
• Use caution when removing unknown plants and weeds.
• Keep potentially poisonous ornamentals away from children and pets.
• If you suspect you touched a poisonous plant, wash immediately with soap and cold water.

Being able to identify poisonous plants helps steer clear of them. But if you suspect contact, seek medical help for severe reactions. With vigilance, you can admire Arkansas' natural beauty while avoiding hazardous plants.

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.