What role does poison ivy play in its natural ecosystem?

Answer 1

Poison ivy provides a food source for many species of birds, as well as larger mammals such as white-tailed deer. Smaller animals use it as shelter. Some animals might even prefer poison ivy so much that they would eat it rather than your garden plants.

It commonly grows on the edges of forests, streams, and roads, or in disturbed areas. The edges of forests are commonly vibrant with several species of briars which serve to create a protective layer to shield the inner forest from harsh weather conditions, as well as providing a layer of shelter for smaller animals. A teacher once explained this to me as a sort of skin for the forest. I suspect that poison ivy provides a similar service, as it is often found among briars and the edges of forests.

The Cherokee revered poison ivy and other "warrior plants" for their ability to quickly respond to disturbances in the forest. When an area is disturbed, say from a storm knocking down trees, or human development, plants like poison ivy and some briars like blackberry or smilax, are some of the first plants to become established in that area. These plants have strong roots and help to limit erosion and condition the soil to prepare it for more forest to grow there in the future.

Poison ivy is not very shade resistant, it needs lots of sun. So it can sometimes be found in the understory of a forest, but most likely if it is then that forest is relatively young. In a mature forest (100+ years) it is unlikely to find poison ivy crawling on the ground, although it still may climb up the sides of some trees.

Ironically, the level of CO2 in the air affects the growth rate and the level of dermatitis causing oil in poison ivy, so with the rising levels of CO2 caused by human activity in our air, the more obnoxious poison ivy becomes.

Also ironically, the more development that occurs, hence the more we disturb ecosystems, the more prolific the population of poison ivy will become.

It seems as if it is seriously trying to combat our growth as we know it.

The Cherokees may have been more right than they knew, or maybe they did know.

Answer 2

poison ivy was around during the time of the dinosaurs and is an adaptive plant that has a potent defense system. i saw on a site that if you take one part Urushiol the resinous sap like oil which is the cause and mix that with 60,000 parts olive oil and can still cause infection.

Answer 3

Poison Ivy is actually considered a weed. It constricts other plants, smothers them, and takes their nutrients. The oil on the plant just happens to give humans a negative reaction as our skin is sensitive to the chemical composition of the oil.

Answer 4

What causes the rash:

There is an oil, called urushiol, that causes an allergic reaction after the first sensitizing exposure. The oil is in the leaves, vines, and roots.

Immunity:

Some people appear to be immune, others become immune. HOWEVER, you can gain or lose immunity, so to assume you can't get it if you never have before is foolish. People change as they age.

You can get it from.....

Although pets can also become contaminated by running through patches of poison ivy, animals do not react to the poison. A sensitive person can be poisoned merely by petting a contaminated animal. The oil is also said to be vaporized by heat such as would be present in a bonfire or a smudge. The oil may be vaporized, or sprayed out like an atomizer, from fresh plants as they are being cut and contaminate a nearby person or the person's clothing even though there is no direct contact with the poison ivy plant.

Why aren't animals affected?

Urushiol ultimately interacts to trigger the allergy with the human T-cell. The same reason a dog can not not get HIV, or the Bubonic Plague, but a human can.