Ethylene is a colorless flammable gas with a faint “sweet and musky” odour when pure. It is a gas that is naturally produced by plants. It also aids in the growth and development of the crop. However, it must be closely monitored as too much ethylene can damage the plants and in turn ultimately affect it value on the market. Decaying foliage, ripening fruit and stressed plants produce more ethylene than young, healthy plants. Other sources which can contribute to the levels of ethylene gas are blowers, trimmers and carts with combustion engines.