Effect of skip‐row planting on cotton yield, biomass and soil moisture in 

South Carolina

J.O. Payero, A. Khalilian, R. Davis, M. Marshall, and A. Nafchi

NRCS‐CIG grant    Drought Adaptation Options: 

1. Conservation Tillage2. Cover Crop3. Deficit Irrigation4. Variable rate irrigation5. Sensor‐based irrigation6. Drought tolerant varieties7. Skip‐row planting

Objectives:

• Demonstrate skip‐row planting to farmers in SC

• Evaluate agronomic, economic and environmental benefits

2013 (Dryland)

• FARMER – (S, SS)• EREC – (S,SS, AS, DS)

Skip (Included)

Solid

Skip

Skip (Included)

Skip (Included)

Solid (Excluded)

Solid (Included)

Rep 1 Rep 1 Rep 1

Solid (Included)

Solid (Excluded)

Solid (Included)

Solid (Excluded)

2014 Planting Configurations:• S, SS, DS, AS

Water regimes:• Dryland• Deficit irrigation • Full irrigation 

2015Solid

Alternate SkipSingle Skip

Water regimes:• Dryland• Deficit irrigation • Full irrigation 

Planting:• S, SS, DS, AS

Measurements

• Soil moisture• Biomass• Yield• Economics

Decagon Watermark

Lint yield 2013

Biomass 2014Biomass (g m‐2)

Configuration Full Deficit  Dryland Average ΔB (%)Solid (S) 1091   1072 856   1006   a 0%Single Skip (SS) 1020 945 933   966 ab ‐4%Double Skip (DS) 809   722 621   717   c ‐29%Alternate Skip (AS) 938 682 689 770 bc ‐23%

ANOVA (P>F):Planting configurationIrrigation

****

Biomass (g m‐1)Configuration Full  Deficit  Dryland Average ΔB (%)Solid (S) 1091 1072 856 1006   a 0%Single Skip (SS) 1359  1260 1244 1288 ab 28%Double Skip (DS) 1618  1444 1242 1435   a 43%Alternate Skip (AS) 1877  1363 1378 1540   a 53%

ANOVA (P>F):Planting configurationIrrigation

****

Dryland Biomass (g/m)

Dryland Biomass (g/m2)

2013 ‐Decagon

Cumulative soil water Gain & Use

2014 ‐Watermark ‐

Cumulative Stress

Economics at EREC 2013

Item Solid SingleSkip

AlternateSkip

DoubleSkip

Seed cost ($/ac) $84.00 $56.28 $42.00 $42.00Yield (lb/ac) 964 1129 765 8312013 cotton price ($/lb) $0.90 $0.90 $0.90 $0.90Gross Income ($/ac) $868 $1,016 $688 $748Income - seed cost ($/ac) $784 $960 $646 $706% income of Solid 100% 122% 83% 90%Income over Solid ($/ac) - $176 (-$137) (-$78)

Economics at FARMER 2013

Item Solid Single SkipSeed cost ($/ac) $84 $56.28Yield (lb/ac) 939 10882013 cotton price ($/lb) $0.90 $0.90Gross Income ($/ac) $845 $979Income - seed cost ($/ac) $761 $923% income of Solid 100% 121%Income over Solid ($/ac) - $162

$0

$200

$400

$600

$800

$1,000

$1,200

Solid Single Skip Alternate skip Double Skip

E5 field Bates field

+$176/acre

‐$137/acre‐$78/acre

Income ‐ Cost of seeds ($/acre)

Conclusions:

• The skip‐planting treatments tended to:– Conserve soil water– Produce bigger plants (higher biomass/m)– Reduce biomass per unit area (g/m2).

• Biomass (and yield) of SS were similar to S.• SS reduced seed cost and increased income, but DS, and AS reduced income.