Irrigation Considerations for Tobacco by George Duncan & Richard Warner Ext. Agr. Engrs. Biosystems & Agr. Engr. Dept. UK Coll. of Agri., Coop. Ext. Service For presentation at TOBACCO EXPO 2003 Jan. 22, 2003 Lexington KY
Considerations: Why increasing interest? Meet Quota, Financial Obligations Top Quality, Grade Market Needs, Contract… Emergency Bail-out? Or Planned Management? Insurance or Investment? Buy it, Use when disaster; Not likely profitable… Invest wisely; manage for profit… Frequency of Dry Years… Two Locations Possible / Potential Results… Data from several studies… Systems… Big Guns, Travelers, Trickle… Costs… Annual, Long-term Benefits…
It’s a Fact: In dry weather… any water applied helps tobacco ever how applied….. Biggest limitation to Irrigation of Tobacco in KY? Source of water! Need to plan for future surface storage! (Ph. I $?) If time runs out; you don’t follow all details… Handouts today; on web: Click on Tobacco Equip. & Facilities
Duncan & Warner, 1/03 BAE, UKY Frequency of dry years, Lexington:
Duncan & Warner, 1/03 BAE, UKY Frequency of dry years, Bowling Green:
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons UK Spindletop Farm (1984)
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons UK Spindletop Farm (1985)
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons UK Spindletop Farm (1986)
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons UK Spindletop Farm (1987)
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons UK Spindletop Farm (1988)
Duncan & Warner, 1/03 BAE, UKY Irrigation Comparisons (4-5 Yr. Avg.) UK Spindletop Farm:
Duncan & Warner, 1/03 BAE, UKY Irrigation Summary UK Spindletop Farm ( ) (Yr, Rain+Irrig, Spr., T.row, T.mid) Yield Increase by Irrigation
Duncan & Warner, 1/03 BAE, UKY Irrigation Trials, Anderson Circle Farm Mercer Co No. Irr. 6.3” rain No. Irr., 6.3” rain 4.8” rain, 4.8” rain, +4.5” Irr. 4.8” rain, + 7.” Irr. 6.3” rain ” Irr.
Duncan & Warner, 1/03 BAE, UKY Non Irrig Irrigated Non Irrig. Source: G. Palmer, Year 2000 Trials: “… Too much irrigation especially early in the season can produce a poor root system and reduce yields..”
Duncan & Warner, 1/03 BAE, UKY Non IrrigatedIrrigatedRaised Bed Irrigated Source: G. Palmer, Yr 2001
Duncan & Warner, 1/03 BAE, UKY Burley Irrigation Trials, Highland Rim Exp. Station, TN Source: J. R. Buchanan,
Duncan & Warner, 1/03 BAE, UKY Source: J. R. Buchanan, R=10.71” +2.86” YIELDYIELD ” +1.46” +0” R=4.40” +4.16” +2.65” +1.10” +3.90” Burley Irrigation Trials, Highland Rim Exp. Station, TN
WHEW…. Can you guarantee Lbs/Ac of yield increase every year with Irrigation???? 200 Lbs? How much?? Let’s look at some Systems, Features…. & Costs, Long term benefits…
Duncan & Warner, 1/03 BAE, UKY Some useful data for Sprinkler Irrigation: Soil Water Holding Capacity: Clay inches/ft of soil Clay-loam “ Silt-Loam “ Sandy Loam “ Infiltration (Application) Rate: Clay 0.15 inch/hour Clay-loam 0.30 “ Silt-loam 0.40 “ Sandy Loam 0.15 “ Suggested reduction rates based on slope: slopeRate reduction 0 – 5% 0 % 6 – 8%20% 9 – 12%20% 13-20%60%
Duncan & Warner, 1/03 BAE, UKY Movable Pipe & Sprinklers:: + Irregular shape, slope fields + Medium pressure, Hp (40-60 psi) + More uniform coverage + Medium cost, used Eq. available - High labor - Lots of pipe, sprinklers… - Wet soil for moving (use skip row) - Evaporation losses (25-35%) - Foliar disease potential
Duncan & Warner, 1/03 BAE, UKY Movable Pipe & Sprinkler Layouts::
Duncan & Warner, 1/03 BAE, UKY Movable Pipe & Big Guns:: + Comparable initial costs + Cover larger area/setting + Less labor to move - More uniform shape, slope fields - High pressure, Hp ( psi) - Wet soil for moving (use skip row) - Evaporation losses (25-35%) - Foliar disease potential - Corner coverage??
Duncan & Warner, 1/03 BAE, UKY Flexible Hose & Traveling Gun:: + Cover larger rectangular areas + Lower labor + More uniform coverage than big guns - Higher initial cost, maintenance - High pressure, Hp ( psi) - Field size, slope limitations - Sod or Skip rows needed - Evaporation losses (25-35%) - Foliar disease potential
Duncan & Warner, 1/03 BAE, UKY Trickle (Drip):: + Low pressure + Lower labor to operate + No foliar wetting (less disease?) + Reduced water needs (evapor.) + More uniform coverage (if level terrain) + Possible automation ?? Same growth, yields? - Lay tube after lay-by or ?, salvage after harvest - Annual replacement of tubing - Moderate initial cost, maintenance - Low pressure, Hp (15-30 psi) - Field elevation limitations (zones) - Proper application rate, intervals
Duncan & Warner, 1/03 BAE, UKY Tobacco Drip Irrigation Design, An Example – 5 ac Given: 5 ac. Field Slope = 2% downslope Field Dimensions = 256 ft. x 850 ft. Row Spacing = 42 inches. One drip tape / row Pond to field = 400 ft., Slope = 0%
Duncan & Warner, 1/03 BAE, UKY Example layout, 5 Ac., 850’ x 256’
Duncan & Warner, 1/03 BAE, UKY Example layout, 50 Ac., 850’ x 256’
Duncan & Warner, 1/03 BAE, UKY Tape Specs. – 5 Ac. Select 5/8 in., T-tape 8” hole sp., 0.33gpm/100ft. Amount of tape : 12,446 ft/ac. (62,230 ft. / 5 ac.) Need 9 7,500 ft. / row = 67,500 ft. Flow rate / ac. = 41 gpm (205 gpm / 5 ac.) Select 4 ~ 51 gpm. Emission 10 psi inlet and 850 ft., 2% downslope = 85%. (12-15 ft elevation change = ~ 50% change in output)
Duncan & Warner, 1/03 BAE, UKY Pipe, Valve and Pump Size Pipe sizes: Header: 1 ¼ in. PE. Submain: 2 in. PE or PVC. Main: 2 in. PVC. Valves: 1 ½ in. Pump: psi (depending on filtration sys.) ft. of head. Pump efficiency = 60%. BHP = 2.53 Purchase 3 HP or 2.5 HP Electric (5-7 Hp Gas.) Filters: Screen or Disk rated for 60+ gpm flow, cleanable
Duncan & Warner, 1/03 BAE, UKY Estimated System Costs: Traveling Gun & Trickle per UT Info, Handout & The Burley Tobacco Farmer, Mar. 2002, Jeremy Stull, Fm. Mgt. Spec., & Randy Womack, Ed. Item Trav. Gun Trickle 5 Acre 20 Acres 5 Acre 20 Acres System $ (loan) $9,400 $20,150 $5,287 $8,936 Anl. Tr. Tape 1,095 4,049 Inv. Per acre $1,880 1,008 1, Anl Anl. Loan Pay. $2,480 $ 5,315 $1,395 $2,357 (5 Yr, 10%) Tr. Tape -- $1,095 $4,049 Total Anl. Cost $2,480 $ 5,315 $2,490 $6,406 Break-Even, Burley 354 lbs. 190 lbs 356 lbs 229 lbs
Irrigation Cash Flow Analysis By Years & Yields GAD,
Duncan & Warner, 1/03 BAE, UKY Summary on Trickle: Understand the management needs… Use means to know soil moisture… Know how much water is being applied… Not an ‘emergency’ system (in my opinion) But can be used to increase yields… Costs/Benefits needs further study…
Duncan & Warner, 1/03 BAE, UKY Summary on Sprinkler: System operation well known… Proven equipment readily available… Used equipment can be economical purchase… Long life with proper care… Custom operation possible… Resale potential…
Duncan & Warner, 1/03 BAE, UKY Thanks…. Lights please… Let’s hope droughts can be managed better in the future… 1983