Doc. # 7430-0710-01 Rev. C
Page
102
9 Appendix C. Managing Agricultural Calculations
9.1 Chill Hours Calculation
Some crops develop their vegetative and fruiting buds in the summer and, as winter approaches,
the already developed buds go dormant in response to both shorter day lengths and cooler
temperatures. This dormancy or sleeping stage protects these buds from oncoming cold weather.
Once buds have entered dormancy, they will be tolerant to temperatures much below freezing
and will not grow in response to mid-winter warm spells. These buds remain dormant until they
have accumulated sufficient chill hours of cold weather. When enough chilling accumulates, the
buds are ready to grow in response to warm temperatures. As long as there have been enough
chill hours, the flower and leaf buds develop normally. If the buds do not receive sufficient
chilling temperatures during winter to completely release dormancy, crops can develop one or
more physiological symptoms.
Refer to the
http://aggie-horticulture.tamu.edu/stonefruit/chillacc.htm
for more information on
this calculation.
Configuring the Chill Hours Calculation
Chill Hours can be performed on any temperature sensor in the eKo network. Typically users
would choose the eKo eS1201 ambient temperature for best results.
