MARICOPA COTTON DEVELOPMENT ADVISORY AUG 31, 2008 PLANTING +/- normal DATE+-------------------------------------------------------------------------+ | | | | | | | | | | | | | | | | | v3624 | 3/15************************************************************************ +2 days | | | | | | | v 3439 | 4/1 ********************************************************************* +1 day | | | | | | | v | | 4/15***************************************************************** 3255 +1 day | | | | | | | v | | 5/1 ************************************************************ 3025 +1 day | | | | | | v| | | 5/15******************************************************** 2800 +3 days | | | | | | | | | | Pin Sus 1st 1" Pk. Bloom Cut-Out Terminate | | head Sq. Flowr Boll +---+---+ +---+---+ +---+---+ | | S M F S M F S M F | +-------+-------+-------+-------+-------+-------+-------+-------+-------+-+ 0 400 800 1200 1600 2000 2400 2800 3200 3600 HEAT UNITS ACCUMULATED FROM PLANTING to AUG 30 v = Heat Units on AUG 23; S,M,F = Short, Medium, and Full Season Varieties HEAT UNITS -------------------------------- Heat Unit (HU) accumulation since Jan 1 = 3952; Last year = 4262; Normal = 3926 HUs since Jan 1 are running about 1 day ahead of normal. HU last week = 187 HISTORICAL STATISTICS -------------------------------- Last Week : AUG 24 - AUG 30 This Week : AUG 31 - SEP 6 HIGH LOW DEWPT HUs RAIN HIGH LOW DEWPT HUs Normal 100 72 60 182 ---- Normal 100 70 57 178 Recorded 99 73 64 187 0.22 2007 102 73 62 190 ESTIMATED WATER USE -------------------------------- Planting date : 3/15 4/1 4/15 5/1 5/15 Water Use (last week): 1.35" 1.56" 1.77" 2" 2" HEAT STRESS LEVELS -------------------------------- Date 8/24 8/25 8/26 8/27 8/28 8/29 8/30 Stress L1 ns ns ns ns ns ns Key : ns = no stress; L1 = Level 1 Stress; L2 = Level 2 Stress WEATHER UPDATE -------------------------------- A weak storm system & trough of low pressure may produce a significant rain event Sunday & Monday. Warm & dry air will follow this system & could signal the end of the monsoon season. Expect sunny & warm conditions from Tuesday on with much lower humidity. Boll maturity estimates can assist growers with de- cisions pertaining to late season irrigations & crop termination and are avail- able at at http://ag.arizona.edu/azmet/Boll_Maturity_2006.pdf. This will be the final advisory for the 2008 season. We would like to thank the Arizona Cotton Research & Protection Council for their funding assistance which helps keep this program functional. Your feedback regarding the future of this program would be most appreciated. Please email Paul Brown at pbrown@ag.arizona.edu.