Drought Calculator

• Arnold Norman, NRCS Fort Worth, TX• Gale Dunn, ARS Fort Collins, CO• Megan Christensen, ARS Fort Collins• NDSU Research Ext. Centers• ARS-Mandan, Miles City

• Monthly Precip.• Plant Growth Curves• Long Term monthly Precip.• Growth Model or Long Term research

• Temperature• Timing and Intensity of precip.• 75% Accuracy

• Forage Growth potential

Carry-Over Potential

• One year-Less than 50% correlation• Several years-negative effect• Carry-over not used by Drought Calculator

Rainfall and Forage Growth

J F M A M J J A S O N D0

0.5

1

1.5

2

2.5

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3.5

4

growthrainfall

• Half of normal March-June• 5 inches in July…too late

Drought Plan

• Protect the Resource• Implement a grazing system• Develop Water• Monitor at Critical Dates• Prepare to sell down• Accept it…Drought Happens

http://www.nrcs.usda.gov/wps/portal/nrcs/site/nd/home/