Pasture / Hay Irrigation options and Management

1. Micro-Irrigation for High Tunnels Pasture / Hay Irrigation options and Management Chris Henry, Ph.D., P.E. Assistant Professor and Water Management Engineer Contact Information: E-mail: cghenry@uark.edu Office: 870-673-2661 Special thanks to Phil Tackerand KSU Extension for inspiration and assistance with this presentation Special thanks to Phil Tacker for inspiration and assistance with this presentation

2. Micro-Irrigation (drip/trickle) The slow, low pressure, precise, application of water and nutrients directly to plants’ roots in a predetermined pattern.

3. What is irrigation and why do we irrigate? • The watering of land by artificial means to foster plant growth (Merriam Webster Dictionary). • Food security

4. Drip Irrigation • Efficiency 95 – 100% • Less disease problems • Reduced weed growth • Fertilizer injection is possible

5. Types of Micro Irrigation • Point Source (includes bubblers) • Line Source • Micro Spray

6. Point Source Application: Individual plantings like orchard trees, grapes etc.

7. Point source emitters ‘Drippers’ Mini sprinklers Spaghetti tubes and drippers 2 GPH emitter Each is rated for dripping at a pre-determined rate usually expressed in Gallons Per Hour (GPH) 1-3 GPH are common sizes

8. Emitters • Pressure: 1 psi minimum (2.3 ft, 0.7 meter elevation) • Typical output: ½, 1, 2 gallons per hour • (2, 4, 8 liters per hour) • Outlet spacing is almost unlimited 2 – 12 feet is most common (0.6 – 3.6 meters) • Run length will be limited at low pressure (1 psi) approx. 15 feet (5 meters) • 5-15 psi on larger systems (> 15 ft)

9. ½” Polyethylene Tubing Emitter Punch Hole Insert Emitter Emitter Installed

10. Slow application Covers 12 – 16 inch diameter circle

11. Can be hidden under mulch – don’t bury emitter in the ground!!!

12. Wire Staple hold in place End Closure

13. Line Source Application: Irrigation in vegetable garden and/or rowed plants

14. Drip Tape • Pressure 1psi minimum (2.3 ft, 0.7 meter elevation) • Flow: approx. 0.5 gpm/100 ft (2 lph/42 meter) • Hole spacing: usually 12 inches (30 cm) • Covers about 12 inch (30 cm) wide strip

15. Concept introduced in England after WWII Adopted in Israel for irrigating crops in the desert American ‘invented’ the modern drip-tape concept Tube in a tube… Built in ‘pressure compensation’ over 5-15 PSI. Allows long runs with uniform water distribution

16. Line source emitters Drip tape or drip tube ‘Leaky’ pipe Weep hose Line can be for dripping at a pre-determined rate usually expressed in Gallons Per Length Hour (GPH) - 25 G/100’/Hr is the most common drip capacity.

18. Drip Tape Wall Thickness 10 to 12 mil Probably best for cost and durability

19. Header line with drip tape connected at each row

20. Fittings connect to header line and to drip tape End of tape is easily sealed

21. Surface water supplies and well water supplies will probably require filtration for micro-irrigation.

22. Micro Spray Application: Solid or close plant spacing

23. Micro Sprays • Pressure: 5 psi minimum (12 feet, 3.6 meters elevation) probably require pump • Flow: 1.5 – 65 gallons per hour (6 – 250 liters per hour) 10 to 15 gph (38 to 57 lph) common • Coverage distance: 2 – 25 feet (0.6 – 7.6 meter) • Various wetting coverage patterns

27. Drip Irrigation • Irrigations are usually frequent since applying low amounts of water • Every 1 to 2 days is common

30. 1 meter minimum

35. Homemade Drip LineOrifice Discharge (gph)

39. http://sowingshalom.blogspot.com/2009/11/simple-bucket-drip-irrigation-system.htmlhttp://sowingshalom.blogspot.com/2009/11/simple-bucket-drip-irrigation-system.html

40. Mulching Combined With Irrigation

41. Large Scale Micro-irrigation

44. 30 “ wide 1 ½” rise Plastic mulch= 48” wide Rolls are 2,000 to 4,000 ft long Cost $110-130/acre

45. Drip Tape or Tube 8 mil (annual) 15 mil (several years) $130-140/roll 1.6c/ft. Rolls or spools 8 mil- 7,500 ft (acre spool) 15 mil- 4,000 ft

46. Single rows or double rows planted on beds Offset Tomatoes Melons Large flowers Nursery stock Centered Peppers Cole crops Strawberries Small Flowers

47. Hand planting Mechanical or ‘punch’ planter

48. Remove a crop and plant another so that the beds are used 2-3 times per season.

49. Components of a drip system • ( backflow preventer) • Filter • 150 mesh screen • Pressure regulator • 5 to 15 PSI • Manifolds • Drip tubing or drip line Optional Pressure gauges Injectors Controllers

50. Screen or mesh filters for well or municipal systems (closed water source) 150 or greater mesh flush valve to clean (pressure gauge to indicate filter clogging)