Appendix G — Critical pressure head values of root water extraction

Table G.1: Critical pressure head values of root water extraction according to Taylor and Ashcroft (1972)
Crop h3h
(cm)
h3l
(cm)
Vegetative crops
Alfalfa -1500 -1500
Beans (snap and lima) -750 -2000
Cabbage -600 -700
Canning peas -300 -500
Celery -200 -300
Grass -300 -1000
Lettuce -400 -600
Tobacco -300 -800
Sugar cane tensiometer -150 -500
blocks -1000 -2000
Sweet corn -500 -1000
Turfgrass -240 -360
Root crops
Onions early growth -450 -550
bulbing time -550 -650
Sugar beets -400 -600
Potatoes -300 -500
Carrots -550 -650
Broccoli early -450 -550
after budding -600 -700
Cauliflower -600 -700
Fruit crops
Lemons -400 -400
Oranges -200 -1000
Deciduous fruit -500 -800
Avocadoes -500 -500
Grapes early season -400 -500
during maturity -1000 -1000
Strawberries -200 -300
Cantaloupe -350 -450
Tomatoes -800 -1500
Bananas -300 -1500
Grain crops
Corn vegetative period -500 -500
during ripening -8000 -12000
Small grains vegetative period -400 -500
during ripening -8000 -12000
Seed crops
Alfalfa prior to bloom -2000 -2000
during bloom -4000 -8000
during ripening -8000 -15000
Carrots at 60 cm depth -4000 -6000
Onions at 7 cm depth -4000 -6000
at 15 cm depth -1500 -1500
Lettuce during productive phase -3000 -3000