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Vegetation Climate Maps

Go to Chilling Hours Maps

Chilling Hours Maps:  Many plants become dormant during the cool season.  If the cool season is not cool enough for a long enough period, many fruit-producing plants have a difficult time knowing when to overcome dormancy.  Like growing degree-day units that are used to track temperature differences over a certain threshold over a period of time, chilling hours offer a way to track length of exposure to optimum dormancy temperatures.  Maps of accumulated and chilling hours and chilling hours departure have been developed for growers to monitor the number of chilling hours over a dormant season based upon popular chilling temperature ranges. For more information, see our "About Chilling Hours Product" page.

Go to Keetch-Byram Maps

Keetch-Byram Drought Index (KBDI):  The Keetch-Bryam Drought Index (KBDI) is one of the few daily indices used to monitor drought.  It is most often utilized in the wildfire community, for it can give a real-time indication of the drying potential for the finer fuels such as grasses and shrubs.  While most commonly used to monitor the risk for wildfire ignition, because it is one of the only drought monitoring indices that are updated on a daily basis, it also offers the potential for many other vegetation applications. To learn more, see our "About Keetch-Byram Drought Index" page.

Go to Stress Degree Day Maps

Stress Degree Days (SDD):  All plants have an optimum range of temperatures for growth.  While it may be obvious that temperatures too low will inhibit growth (if not damage the plant), temperatures that are too high can cause stress for the plant.  Stress Degree Days (SDD) are a way of tracking how much stress a type of plant has been subjected to within its growing season. To learn more, see our "About Stress Degree Days" page.

Go to GIS Map Products

GIS Vegetation Climate Maps:  The GIS Vegetation Climate Map contains the Chilling Hours, Keetch-Byram Drought Index, and Stress Degree Days maps, all in one GIS interface. To learn more about the individual maps, see their "About" pages.