Cotton Petiole Logic – 2012
Links: UGA Simplified Cotton Petiole Program – 2011 Original N and P logic for periods 1-10 Original program logic Petiole Submission Form Announcement
Notes: Logic below is based on links 1 and 2. N in the Condition column is Nitrate-N. P2 is phosphorus at period 2, P3 is phosphorus at period 3, etc.
Condition	Recommendation
Period 1 – Week before first bloom [Period 1 is not an option on the form, but we can provide recommendations if needed.]
P<800 and N<9000	Unless as much as 40 pounds of P2O5 per acre was applied pre-plant or later, sidedress an N-P2O5 fertilizer if possible (5-15 pounds of N and up to 50 pounds of P2O5 per acre).
N>=13000	Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=7000 and N<12999	Nitrogen is adequate.
N>=5000 and N<6999	N is low but not strongly deficient. The next sample period is very important.
N<5000	If squaring rate or insect is fair or poor: Apply 0.2 pounds of actual boron and 2 pounds N as urea in 2 to 5 gallons of solution per acre. Urea aids in boron uptake. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects. If squaring rate and insect control are good or excellent: If more than 40 pounds of soil N was applied: N is deficient. Apply 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre. If less than 40 pounds of soil N was applied: Apply 15 pounds of N per acre to the soil. Also apply foliar N of 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre.
Period 2 – Week of first bloom
P<800 and N<4500	Unless as much as 40 pounds of P2O5 per acre was applied pre-plant or later, sidedress an N-P2O5 fertilizer if possible (5-15 pounds of N and up to 50 pounds of P2O5 per acre).
N>=12500	Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=4500 and N<12500	Nitrogen is adequate.
N<4500	If squaring rate or insect control is poor: Apply 0.2 pounds of actual boron and 2 pounds N as urea in 2 to 5 gallons of solution per acre. Urea aids in boron uptake. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects. If squaring rate and insect control are fair to excellent: If more than 40 pounds of soil N was applied: N is deficient. Apply 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre. If less than 40 pounds of soil N was applied: Apply 15 pounds of N per acre to the soil. Also apply foliar N of 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre.
K<2.5	If the yield potential is at least 1 ½ bales per acre, apply 50 pounds K2O per acre to the soil.
K>=2.5 and K<3.5	If the yield potential is at least 1 ½ bales per acre, and less than 50 pounds K2O per acre was applied to the soil based on the soil test, apply 50 pounds K2O per acre to the soil. Otherwise, no K2O is needed.
Period 3 – Bloom plus one week
N>=11000 and (P<P2-400)	Analyses suggest fruit loss. Check for cause.
N>=11000	Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=3500 and N<11000	Nitrogen is adequate.
N<3500	If fruiting rate or insect control is poor: Apply 0.2 pounds of actual boron and 2 pounds N as urea in 2 to 5 gallons of solution per acre. Urea aids in boron uptake. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects. If fruiting rate and insect control are fair to excellent: If less than 40 pounds N per acre applied to the soil, and soil moisture excessive, good, or slightly dry: Apply 15 pounds of N per acre to the soil. Also apply foliar N of 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre. If less than 40 pounds N per acre applied to the soil, and soil moisture droughty: N is deficient. Apply 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre. If more than 40 pounds N per acre applied to the soil: N is deficient. Apply 5 pounds N as urea in 5 to 10 gallons of water or liquid insecticide per acre.
K<2	If the yield potential is at least 1 ½ bales per acre, apply 10 pounds potassium nitrate (KNO₃) or its equivalent as a foliar application.
K>=2	Petiole potassium is sufficient; do not apply more K.
Period 4 – Bloom plus two weeks
N>=9500 and (P<P3-400 or P<P2-600)	Analyses suggest fruit loss. Check for cause.
N>=9500	If boron was not recommended based on earlier analysis: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=2500 and N<9500	Nitrogen is adequate.
N<2500	If fruiting rate or insect control is fair or poor: Apply 0.2 pounds of actual boron and 2 pounds N as urea in 2 to 5 gallons of solution per acre. Urea aids in boron uptake. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects. If fruiting rate and insect control are good or excellent: If less than 60 pounds N per acre applied to the soil, and soil moisture good for past two weeks: Apply 15 pounds of N per acre to the soil. If less than 60 pounds N per acre applied to the soil, and soil moisture dry or droughty this or last period: Apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of solution per acre by airplane, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N. If more than 60 pounds N per acre applied to the soil: Apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of solution per acre by airplane, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N.
K<1.75	Apply 10 pounds potassium nitrate (KNO3) or its equivalent as a foliar application.
K>=1.75	Petiole potassium is sufficient; do not apply more K2O.
Period 5 – Bloom plus three weeks
N>=7500 and (P<P4-400 or P<P3-600)	Analyses suggest fruit loss. Check for cause.
N>=7500	If boron was not recommended based on earlier analysis: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=1500 and N<7500	Nitrogen is adequate.
N<1500	If fruiting rate or insect control is fair or poor: Apply 0.2 pounds of actual boron and 2 pounds N as urea in 2 to 5 gallons of solution per acre. Urea aids in boron uptake. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=750 and N<1500	If fruiting rate and insect control are good or excellent: Apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of solution per acre by airplane, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N.
N<750	If fruiting rate and insect control are good or excellent: N is deficient. Apply foliar N as follows: (a) 9 pounds of N as urea in 20 gallons of water or liquid insecticide per acre with ground equipment, or (b) if necessary, make two applications of 4.5 pounds of N as urea (total 9 pounds of N) in 5 to 10 gallons of water or liquid insecticide. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N.
K<1.75	Apply 10 pounds potassium nitrate (KNO3) or its equivalent as a foliar application.
K>=1.75	Petiole potassium is sufficient; do not apply more K2O.
Period 6 – Bloom plus four weeks
N>=7000 and (P<P4-800 or P<P5-400)	Analyses suggest fruit loss. Check for cause.
N>=7000	If boron was not recommended at previous test periods: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=1000 and N<7000	Nitrogen is adequate.
N<1000 and ( (P5 sampled and P>=P5+400) or (P4 sampled and P>=P4+600) )	If fruiting rate and insect control are good or excellent: N is deficient. Apply foliar N as follows: (a) 9 pounds of N as urea in 20 gallons of water or liquid insecticide per acre with ground equipment, or (b) if necessary, make two applications of 4.5 pounds of N as urea (total 9 pounds of N) in 5 to 10 gallons of water or liquid insecticide. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N.
N<1000 and ( (P4 and P5 not sampled) or (P<P4+600 or P<P5+600) )	Apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of solution per acre by airplane, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment. Under droughty conditions, do not apply more than three consecutive weekly foliar applications of N.
K<1.75	Apply 10 pounds potassium nitrate (KNO3) or its equivalent as a foliar application.
K>=1.75	Petiole potassium is sufficient; do not apply more K2O.
Period 7 – Bloom plus five weeks
N>=6000 and (P<P6-400)	Analyses suggest fruit loss. Check for cause.
N>=6000	If boron was not recommended at previous test periods: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=1000 and N<6000	Nitrogen is adequate.
N<1000	If fruiting rate and insect control are good or excellent, and if climate and fruiting conditions are good or excellent, apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of water or liquid insecticide solution per acre by air, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment.
K<1.75	Apply 10 pounds potassium nitrate (KNO3) or its equivalent as a foliar application.
K>=1.75	Petiole potassium is sufficient; do not apply more K2O.
Period 8 – Bloom plus six weeks
Always	If boron has not been applied to this crop: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=500 and N<4000	Nitrogen is adequate.
N<500	If boll load or insect control are good or excellent, and if climate and fruiting conditions are good or excellent, apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of water or liquid insecticide solution per acre by air, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment.
Period 9 – Bloom plus seven weeks
N>4000	If boron has not been applied to this crop: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=500 and N<4000	Nitrogen is adequate.
N<500	If boll load or insect control are good or excellent, and if climate and fruiting conditions are good or excellent, apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of water or liquid insecticide solution per acre by air, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment.
Period 10 – Bloom plus eight weeks
N>4000	If boron has not been applied to this crop: Apply 0.2 pounds of actual boron in 2 to 5 gallons of water or liquid insecticide per acre as a foliar spray. Boron hastens translocation of N and sugars, improves fruiting, and may make plants less attractive to insects.
N>=500 and N<4000	Nitrogen is adequate.
N<500	If boll load or insect control are good or excellent, and if climate and fruiting conditions are good or excellent, apply foliar N as follows: (a) 5 pounds of N as urea in 5 gallons of water or liquid insecticide solution per acre by air, or (b) 7 pounds of N as urea in 15 gallons of water or liquid insecticide per acre with ground equipment.