Number sign. Not to be confused with the Chinese character äº, the sharp sign (â¯), the viewdata square (â), the numero sign (â), the equal and parallel to symbol (â) or the game Tic-tac-toe's grid. The symbol # is most commonly known as the number sign, hash, or pound sign.
The poison ivy rash is not contagious. When a person touches the poison ivy leaf, a substance on the surface of the leaf (a resin) rubs off. Over the next 48 to 72 hours the skin reacts to the resin by becoming red and developing bumps and blisters at and around the site where the resin was.
Poison ivy can take the form of an erect shrub or climbing vine or grow in large colonies along the ground. Poison ivy has aerial rootlets that it uses to attach to the bark of trees. The rootlets have a hairy appearance. Twigs of poison ivy may be covered with fine hairs.n oily resin called urushiol, which is found in all parts of the plant, is what causes skin rashes when people come in contact with it. People vary in their sensitivity to poison ivy, but may become more sensitive after repeated exposure to it. One common misconception is that the poison ivy rash itself is contagious.