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FACTORS THAT AFFECT TRANSPIRATION
PLANT FACTORS
1) leaf area - smaller leaf area decreases transpiration

2) leaf orientation - vertically orientated leaves decrease transpiration

3) leaf surface - waxy, hairy or shiny leaf surfaces decrease transpiration

4) stomata - when stomata are closed, transpiration decreases

ENVIRONMENTAL FACTORS
1) humidity - high humidity decreases transpiration

2) temperature
     a) low temperature decreases transpiration.
     b) high temperature increases transpiration, but when it gets too hot the stomata close, 
          then transpiration may decreases.

3) light intensity
     a) darkness decreases, because stomata close, (except for CAM plants open at night).
     b) high light intensity increases temperature which increases transpiration, until stomata
         close then transpiration may decrease; occurs midday during heat of summer.

4) wind - as wind increases, transpiration increases, but if the wind gets too high, then the 
         stomata close and transpiration decreases

5) soil water
     a) when soil is moist, transpiration occurs according to the above factors
     b) when soil is too dry, stomata close causing transpiration to decrease (overrides
         the above factors)

TECHNIQUES USED TO DECREASE TRANSPIRATION
1) mist or spray foliage 
     a) in propagation an intermittent mist system is used
     b) mid-afternoon sprinkler irrigate plants in greenhouses/nurseries

2) decrease light intensity - grow plants under shade

3) harden-off seedlings
     a) decrease watering,
     b) decrease temperature, or
     c) decrease fertilizer, especially N.

4) antitranspirants - chemicals that close or clog stomata.
     Two Types
     a) physiologically cause stomatal closure
   b) wax, resin or latex that clogs stomata