C.W. Bednarz and W.D. Shurley University of Georgia and W.S. Anthony USDA-ARS Losses in Yield, Quality, and Profitability of Cotton From Improper Harvest Timing

IS THIS PROBLEM DUE TO: ENVIRONMENT? Soil Type MANAGEMENT? Varieties Population Densities Insect Control Harvest Timing

PERCENT HARVESTED BY WEEK (5 year average)

CommodityPlantedHarvested GA Cotton4/25-5/2510/5-11/15 GA Peanut4/25-5/209/10- 10/15 Cotton and Peanut “Most Active” Planting and Harvest Dates

What is This Harvest Delay Costing Us? (Objectives of Study) Investigate the effects of harvest timing on fiber properties in general and percent uniformity in particular. Investigate the effects of harvest timing on lint yield. Investigate the effects of harvest timing on profitability.

Cotton Defoliation Timing Study CPES - Ponder Farm Established 13 treatments (weeks) in the study area. Applied harvest aids every week for 13 weeks (NACB and %OB) Machine picked each plot two weeks after applying harvest aids. Seed cotton ginned on mini gin and the USDA-ARS Lab. HVI and AFIS on lint samples (3 per plot). Data subject to ANOVA.

Week% OBHvDAP% OBHvDAP% OBHvDAP Harvest Dates

Uniformity 1998 ab a a a a aa a a b P>F

Uniformity 1999 P>F cd abc ab a bcd e cd bcd cd de

Uniformity 2000 P>F d cd bc a abc ab d d d bc cd d

L(n)CV 1999 F = 4.17** c c c cc c bc ab aa

L(n)CV 2000 F = 6.19** bcd e de e cde abc bc abc ab a a

Why is Uniformity Changing? Increasing up to 70% OB Crop Maturity? Non-determinate Crop Decreasing after 70% OB Crop Weathering?

Strength 1998 P>F a b c bc c cde f cd ef de f def

Strength 1999 P>F ab aa abc bc d d cd d d

Strength 2000 F = 13.91** a a bbcbcd cdef def efg bcde fg g

HVI-UHM 1998 P>F a a a a a a a a aa a a a

HVI-UHM 1999 P>F a a a a a a a a a a a a a

HVI-UHM 2000 F = 3.94** ababc a bcde defcdef f bcde def f

AFIS-Length(n) 1999 P>F ab aaa a a abc bcd cd d

AFIS-Length(n) 2000 F = 8.70** cd ab abc a bcdcd defg deefg fg gg

AFIS-SFC(w) 1999 P>F cd bcd d d d d abcd abc ab abc a

AFIS-SFC(n) 2000 F = 9.24** def fg g efg def bcd cde bc ab a abc a

HVI Micronaire 1998 P>F c bc c ab a a a

HVI Micronaire 1999 P>F ee d bcdcd abc a ab

HVI Micronaire 2000 F = 59.40** g f e bcde cde bcdbca de bcbcdeab

Week EventsTotalEventsTotalEventsTotal Inches TOTAL Rainfall During Harvest

Week Color Grades

Week Cents per pound Sum of Premiums/Discounts

Week % OBLint% OBLint% OBLint c17795 f9633 f ab31881 ef30823 e ab de57896 de ab ab ab ab ab b a a ab ab bc ab ab cd bc ab bc a bc bc ab ab bc bc bc cd abc abc cd Lint Yields

CONCLUSIONS Application of Harvest-Aids at 60-80% Open Boll: Maximized Length Uniformity Fiber Length Lint Yield (1999) Profit (1999) Minimized Short Fiber Content