Facts about Poison ivy

13 Poison ivy facts


This inconspicuous and common plant is known for its injurious properties. Contact with any part of the poison ivy may cause burns, pain, and blistering. It is not poisonous, but causes unpleasant and severe allergic reactions in most people due to its urushiol content.

Poison ivy
It is native to North America and Asia.
Two Poison Ivy species are found in North America and one in Asia.
American species differ in plant appearance.
  • Western poison ivy is a more shrub-like plant that usually grows to 1m (3ft) height.
  • Eastern poison ivy is often climbing or trailing plant with long stems. There are eight subspecies of eastern poison ivy.
Poison Ivy grows in Canada and most of the contiguous United States.
It is widely spread throughout the central and northern parts of the continent, but the eastern poison ivy is found even in the mountainous regions of Mexico.
Contrary to popular opinion, it's not poisonous.

It has a bad reputation because of its skin-irritating attributes.

Contact with plant sap may result in itching, pain. The substance responsible for the appearance of the above symptoms is urushiol.

Urushiol is an organic compound that causes an allergic reaction in most people.
It is produced not only by poison ivy but also by poison oak, poison sumac, or the Chinese lacquer tree. After contact, it is absorbed by the skin very quickly. It takes about 10 minutes for 50% of the urushiol to penetrate deep into the skin.
Urushiol does not only adhere to the skin.
It may also stick to clothing, shoes, and anything rubbed against the plant and remain harmful to humans for many days after.
About 15 to 25 percent of people are immune to urushiol.
It is crucial to wash the body as soon as possible.
A quick wash with soap and water is advisable to escape unpleasant conditions. The sooner the better because after a few minutes, the urushiol penetrates the skin and cannot be removed by washing.
Over 350 thousand people in the USA suffer from urushiol contact each year.
The rash typically lasts about a week, but there are cases where it lasted more than a month.
Poison ivy has trifoliate leaves.

Their color ranges from light to dark green, and the leaves usually darken with age. 

The leaflets are on average about 10 cm (4 in) long, and the maximum leaf length is up to 30 cm (11,8 in).

In autumn they turn bright red or yellow and are shed in winter.

It is one of the first plants that change leaf colors in autumn.
Yellow and Red leaves are still dangerous and can give you a rash, so be careful.
Blooming season lasts from May to July.
The flowers are small, grow in clusters and are yellowish-white or greenish-white in color.
The flowers of Poison Ivy develop into green berries in late summer. After ripening in fall, they turn white.
The berries are edible for birds but not for people. Birds eagerly consume berries and help spread ivy seeds over long distances.
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