1. Master Gardener Class 2011 Carol Fryer

2. How I Did My Research GoogleGoogle search by topic and specify a university or extension website Search examples:Search examples: degree days site:edu growing degree days site:vt.edu degree days site: ext.vt.edu

3. Results of Google Search

5. My Choices

6. So What are Growing Degree Days? Growing Degree Days : Integrated Pest Management tool Tracks and predict stages of insect development based on temperature Uses a mathematical calculation system Can compare from year to year Easy and fun to do!

7. What does it involve? * Record daily high and low temperatures and find an average temperature for the day. Example: Example: 70º Max & 50° Minimum temp/2 = 60° average daily temperature *Subtract 50º Base Temperature from average temperature: 60 - 50 = 10 Growing Degree Days (GDD) *Add the GDDs for the Accumulated Growing Degree Days(AGDD) and compare to a chart of insect development by degree days.

8. Mathematical Equation of GDD Max temperature + Minimum Temp /2 minus Base Temp = Daily GDD 70°(MT) + 50°(min t) /2 = 60°– 50°(BT) = 10 GDD

9. Charting

10. Winfield Solution GDD Calculator

11. GDD for Insects University of NH - Growing Degree Days for Insect Management, Nancy E. Adams, Extension Educator, Agricultural Resources

12. Insect GDD - Cornell University

14. Summary – GDD & Insect Control Record daily high and low temperatures and calculate the average temperature Subtract the base temperature from the daily average Keep a daily accumulated total of the Growing Degree Days Check plants for signs of pests Use list of insect development to predict time periods for potentials pests

15. Don’t Forget the Beneficial Insects

16. Resources Websites: www.extension.unh/agric/GDDays/Do cs/growch.pdf www.gardening.cornell.edu www.virginiafruit.ento.vt.edu/Underst anding-Degree-Days.html www.wfsag.com/UserFiles/File/GDDCalcula tor.xls

17. Questions

18. The END Potato insect larva - handmade candy