Answer:
Congress grass can lead to various kinds of allergies to humans. The grass attacks your respiratory system, which can further lead to sinus, rhinitis, bronchitis as well as various forms of asthmatic issues. It can also lead to skin allergies and dermatitis. The grass spreads its effect through either direct touch or through air.
Other mediums which cam cause the spread of congress grass( also known as carrot grass) are water, cattle, vehicle and humans which become carrier to the essence of grass. Further, when flowers appear from grass, it spreads into the environment through pollen. The grass is more dangerous if it appears in "not so open" surroundings like between colonies. Since the cattle do not graze this grass, it remains growing like anything. Cause of various ailments-particularly allergies-this grass is bane to the health and well beings of humans. Incidentally, congress grass depletes fertility of the land on which it grows.