Precision Irrigation and Fertigation What is Irrigation Irrigation

Precision Irrigation and Fertigation

What is Irrigation? Ø Irrigation is the application of water to a crop for assisting the production of a crop. What is precision? Ø A degree of mutual agreement among a series of individual measurements, values, or results.

What are we looking for in precision irrigation? Irrigation Efficiency and/or Uniform Coverage Ø Plus site-specific application Ø Efficiency is what you get out, for what you put in. Efficiency = output / input OR Water stored in root zone / water delivered to the field

Decreased Efficiency Wind Drift Evaporation from vegetation Evaporation from soil surface Infiltration Runoff Deep percolation

Flood Drip Furrow Spray

Spray Irrigation Evaporation (Major Loss) l Wind speed l Humidity l Air temperature l Canopy density l Sprinkler evaluation l Sprinkler pressure Ø Deep Percolation (Minor Loss) l System uniformity l Total application depth Ø Runoff (Minor Loss) l Application rate l Slope l Vegetation Density Ø

Furrow Irrigation Ø Evaporation (Minor Loss) l l l Ø Deep percolation (Major Loss) l l l Ø Wind speed Humidity Air temperature Unit flow rate Field length Soil texture Field slope Total application depth Runoff (Major Loss) l l l Unit flow rate Field slope Soil texture

Drip Irrigation Ø Evaporation (Minor Loss) l Minor soil surface evaporation for drip Ø Deep percolation (Minor Loss) l l System uniformity Total application depth Ø Runoff (Minor Loss)

How to Improve Irrigation System Ø Night Irrigation – Low temp, low wind, high humidity Ø Lower operating pressure – bigger droplet size Ø Low drift nozzles – bigger droplet size Ø New Technology

Low Energy Precision Application (LEPA) Ø Irrigates with the plant rows Ø Drops water in the furrow Approximately 90% application efficiency

Efficiency Ø Standard Multi Sprinkler 75 -80% Ø Moving Multi Sprinkler l LEPA Ø High Pressure Gun Ø Standard Flood Ø Drip Irrigation 90+% 60 -75% 40 -70% 90% A high efficient irrigation system will help increase the precision of the application of water and nutrients to the plant.

Fertigation / Chemigation The use of an irrigation system to apply the necessary application of nutrients or chemicals to the crop.

Management Need to know and understand the equipment.

Advantages Ø Uniformity of application Ø Prescription applications Ø Economics - expense Ø Timelines Ø Incorporation and Activation Ø Reduced Compaction Ø Operator hazard

Disadvantages Ø Calibration of equipment Ø Additional equipment Ø Environmental Hazard Ø Increased application times Ø Unnecessary Water Applications

Why use Fertigation? Ø Your irrigation system does the work. Ø Overfeeding and Underfeeding is decreased. Ø Dry applications need water to dissolve the granules. Ø With precise application, the overall amount of chemicals applied is reduced vs. the dry application.

Precision Irrigation The use of fertigation or chemigation with site-specific technology. Ø Technology l l l GPS – locate soil type, water holes, weeds, obstructions, and boundaries GIS (Geographical Information System) works with data captured from spatial reference points. VRT (Variable-rate controllers) System “Brain” sets the rate of application dependent on soil type, slopes, ponds…etc. Weather Station / Mesonet (ET rate) Green Seeker / Weed Seeker • NIR (Near Infrared Band) • Red (Red Band) • Thermo sensor

Site Specific Irrigation/Fertigation Pivot Animation

Sources Ø Ø Ø Ø www. florence. ars. usda. gov/ www. betterpivots. com/how. html http: //weather. nmsu. edu/ www. nrw. gld. gov. au/ www. ag. ndsu. nodak. edu/abeng/ www. fertigationsystems. com http: //msucares. com/pubs/pulications/p 1551. htm Dr. Kizer. Oklahoma State University. April 18, 2008

Questions?