Growth potential for C3 and C4 grasses
The animated GIFs for cool season grasses (C3_GP) and warm season grasses (C4_GP) were created by plotting Growth Potential (GP) based upon 30 year normal average monthly temperature (data from National Oceanic and Atmospheric Administration 1950-1980 - tempertures are likely a little higher now, but the trends will be similar) for each zipcode by latitude and longitude. There are about 40,000 data points plotted per month. The GP model has been modified a couple of times over the years, most recently to maximize C4 growth potential when average temperature exceeds the estimated optimum temperature for C4 grasses (88 F or 31.1 C). Refer to this graph for an illustration of the GP model functions.
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MLSN and GP at the 2017 GIS
Jason Haines (@PenderSuper on Twitter) and Larry Stowell (@paceturf on Twitter) taught a half-day course on Minimum Levels for Sustainable Nutrition (MLSN) guidelines and Growth Potential (GP) to more than 100 golf course superintendents from around the world. The slide presentation and handout materials used for the course have been provided at the links below:
Global Soil Survey 2015 Report
The Global Soil Survey was launched in August, 2013 to enlist turf managers from around the globe to collaborate in the development of new, more sustainable turf nutrient guidelines. After two years, there are several key results to report:
- The Second Annual Report on the Global Soil Survey was issued November, 2015.(The first report was issued September, 2014). The new report has links to all the data, a summary of results, an updated location map and more.
- We have designed a repository of all of the Global Soil Survey data. This will allow anyone who is interested to access the annual report, study or analyze the Survey data, or review our analytical approach.
- Information and results of the Global Soil Survey have been shared with researchers and turf managers in the following presentations and articles:
- A presentation, Only what the turf needs: Updating the Minimum Levels for Sustainable Nutrition Guidelines on the results of the Global Soil Survey.
- Getting there first: Global Soil Survey for Sustainable Turf guides superintendents to reduce nutrient inputs. Golf Course Industry, August 5, 2014.
- Global Soil Survey results challenge conventional guidelines. Golfdom, April 22, 2014.
- Sustainable fertilizer use, by superintendent Jason Haines, Pender Harbor Golf Club, January, 2014.
- Just what the grass requires: using minimum levels for sustainable nutrition. by Micah Woods, Larry Stowell and Wendy Gelernter. January, 2014 Golf Course Management article.
- A Golf Course Industry podcast from Dr. Micah Woods, Share your soil, on the Global Soil Survey.
Sign up for the Global Soil Survey!!. Sign up by mail or sign up online, and become part of history!!
More information on the Global Soil Survey for Sustainable Turf: