<P> The effect of wind velocity on the transpiration rate of plants . </P> <Li> <P> The effect of humidity on the transpiration rate of plants . </P> </Li> <P> The effect of humidity on the transpiration rate of plants . </P> <P> During a growing season, a leaf will transpire many times more water than its own weight . An acre of corn gives off about 3,000--4,000 gallons (11,400--15,100 liters) of water each day, and a large oak tree can transpire 40,000 gallons (151,000 liters) per year . The transpiration ratio is the ratio of the mass of water transpired to the mass of dry matter produced; the transpiration ratio of crops tends to fall between 200 and 1000 (i.e., crop plants transpire 200 to 1000 kg of water for every kg of dry matter produced). </P>

Explicate three methods that make transpiration to occur in plants