YUMA VALLEY  COTTON DEVELOPMENT ADVISORY
                                    AUG 31, 2008 
PLANTING                                                               +/- normal
DATE+-------------------------------------------------------------------------+
    |            |   |     |      |         |           |           |         |
    |            |   |     |      |         |           |           |    4046 |
2/1 **************************************************************************-1 day
    |            |   |     |      |         |           |           |   3969  |
2/15**************************************************************************-1 day
    |            |   |     |      |         |           |           |   3844v |
3/1 **************************************************************************-1 day
    |            |   |     |      |         |           |           |    v3713|
3/15**************************************************************************-1 day
    |            |   |     |      |         |           |           |v  3513  |
4/1 **********************************************************************    -1 day
    |            |   |     |      |         |           |           |         |
    |           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 = 4145;  Last year = 4312;  Normal = 4232
HUs since Jan 1 are running about 3 days behind normal.
HU last week = 204


HISTORICAL STATISTICS 
--------------------------------
  Last Week : AUG 24 - AUG 30             This Week : AUG 31 - SEP 6
           HIGH  LOW DEWPT HUs  RAIN               HIGH  LOW DEWPT HUs
  Normal    105   77   63  200  ----       Normal   104   76   60  198
  Recorded  100   79   69  204  0.28         2007   106   81   62  208


ESTIMATED WATER USE 
--------------------------------
      Planting date :     2/1    2/15      3/1    3/15     4/1
Water Use (last week):     .96"   1.05"     1.2"   1.36"    1.6"


HEAT STRESS LEVELS 
--------------------------------
Date     8/24   8/25   8/26   8/27   8/28   8/29   8/30  
Stress    L1     L1     L1     L2     L1     L1     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.