Barley Growing Degree Days
The North Dakota State Climate Office developed September’s featured climate tool, which is used primarily by those in agriculture. This utility provides barley growing degree days (GDD) and Haun growth stages for over 70 stations that comprise the North Dakota Agricultural Weather Network (NDAWN). As the most common temperature index to estimate plant development, GDD are useful for scientists, crop consultants, and producers for planning crop management decisions such as irrigation, pesticide application timing, or harvest scheduling. While growth stages of barley can be determined by visual inspection, using the accumulation of heat or temperature units above a base temperature (in which no growth occurs) supplies a good estimate as well. This utility uses a base temperature of 32°F (0°C) for barley.
The tool highlighted here allows the user to view either a table of raw values or maps of barley GDD and Haun growth stages for one or more of the NDAWN stations. The planting and end dates must be entered, and options to compare GDD from the current year to previous years and normal values are also available. Note that this utility has parameters set to avoid adding GDD when plant growth is prevented or slowed due to extreme high or low temperatures. Additional instructions for navigating the tool are also available on the website.
The information supplied by this tool has proved to be very useful for farmers in North Dakota. Similar web applications are available for different crops such as corn, canola, sugarbeet, wheat, and sunflower, with of course different settings for the base and threshold temperatures for the growth stages. These can be found at the NDAWN site: http://ndawn.ndsu.nodak.edu/applications.html.
Each month, an AASC-developed climate tool will be featured from our “Climate Tools Database”, expanding on the short description already listed in the table.
Assistant State Climatologist OWSC