1. Irrigation Requirements Arboriculture HORT 350 Spring 2001

2. Arboriculture Irrigation Requirements Terms: –water potential (Ψ, kPa, MPa) –Field capacity –Permanent wilting point –Available water –macropores, micropores –crop coefficient

3. Arboriculture Irrigation Requirements Field Capacity~0.03 MPa –amount of water held against the force of gravity; usually measured 24 h after irrigation Permanent Wilting Point ~1.5 MPa –amount of water resulting in wilting from which plant will not recover; developed for agronomic crops

4. Arboriculture Irrigation Requirements/ Harris et al. 1999 ~30 kPa ~1500 kPa

5. Arboriculture Irrigation Requirements/ Harris et al. 1999 mm water/ 600 mm soil

6. Arboriculture Irrigation Requirements/ Harris et al. 1999 Infiltration rate (mm/h)

7. Arboriculture Irrigation Requirements/ Harris et al. 1999 Water content Saturated

8. Time (min) Arboriculture Irrigation Requirements/T ransplanting Water Loss (mg/cm 2 ) Water Lily

9. Arboriculture Irrigation Requirements/ Harris et al. 1999 June December

10. Arboriculture Irrigation Requirements/ Las Cruces, NM Inches

11. Dr. Death’s Tree Care Guide Alfalfa Irrigation Requirements Water (in/mo)

12. Dr. Death’s Tree Care Guide Pecan Irrigation Requirements Water (in/mo)

13. Dr. Death’s Tree Care Guide Afghan Pine Irrigation Requirements Water (inmo)

14. Dr. Death’s Tree Care Guide Las Cruces’ Tree Water Requirements Water Use (in/yr) After Sammis & Jerigan 1992

15. Arboriculture Irrigation Requirements/ Sammis

16. Dr. Death’s Tree Care Guide Las Cruces’ Tree Water Requirements

17. Dr. Death’s Tree Care Guide Las Cruces Water Requirements Crown diameter = 15 ft Well diameter = 10 ft Ratio= 1.5:1 Crown area = 177 ft 2 Well area = 79 ft 2 Ratio = 2.2:1 How much water does my tree really need? Therefore, if my tree needs 1” of water, I need to supply 2.2” to the well.

18. Arboriculture RainBird ‘DriWater’ Irrigation Supplement Slow release water over 90 d (but check within 45-60 d) Cost $3/ea Use: –1 gal = 2- 4 –5 gal = 4- 8 –15 gal = 11-16 –24” B&B = 18-20