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Sustainable Fertilizer Use

One of the most over-used words in the turf industry the past few years has been "sustainable." People throw it around (and I'm just as guilty) but don't really have much data to back it up. What is sustainable? On the golf course it means using the minimum required resources to produce the expected conditions. This fall I decided to take part in the Global Soil Survey (GSS) to really get a good idea of how sustainable my fertilizer practices really were.

I sent off my samples and received my comprehensive soil test results typical of PACE Turf. Here are my test results.

And here is where the test results differ from your typical soils tests:

As can be seen from the above tables, I don't currently have any nutrient deficiencies according to the Minimum Level for Sustainable Nutrition guidelines (MLSN). I would also have to agree as my greens look pretty good. In Table 2 you basically get a report card of how you are doing. Table 3 tells you how much nutrients you have in the reserves and Table 4 tells what you need to add in case you have any nutrient deficiencies. Pretty Cool!

Now any smart person could probably figure this out. It's a few not too complicated calculations. The really cool thing about the GSS is that the data you submit (soil samples from good performing turf) goes into the database that helps refine the MLSN guidelines! As turf managers get more sustainable in the fertilizer practices we should get an even better idea of what truly sustainable fertilizer practices look like!

These results make it quite clear that I still have some work to do to become more sustainable in my fertilizer practices. Apparently I have been over-applying most elements over the years so for the next year this is what I am required to add as fertilizer.

Yep, that's right. Next year I am required to add almost nothing other than nitrogen to my putting greens! With the GSS we are instantly able to become as sustainable as possible. They give you fertilizer requirements for a wide range of nitrogen rates so you can match it for any circumstance and climate. If I apply nothing but nitrogen next season I will only be applying what the plant needs. This is only made possible, however, from years of over fertilizing and eventually I have to expect that a more complete fertilizer program will have to resume. But for the next season at least, I can ride the coat tails of "half assed and guessy" fertilizer practices of years past.


Disclaimer WARNING! Charts ahead, leave now if you find info-graphics offensive.


Now you might be wondering, how does this actually impact my operation? Here are a few charts.

The following chart shows how the total amount of fertilizer applied to my course has gone down. The biggest improvements have come from using simple source fertilizers instead of blended fertilizer. In 2012 I switched to UMAXX granular on fairways and was able to get rates much lower. In 2013 I got a new sprayer and was then able to apply straight urea to the fairways further driving down amounts of fertilizer required. This not only has an impact on fertilizer cost and environmental impact, but also on shipping costs and the resultant carbon emissions from that process.



The changes to my fertilizer programs have also made a big impact on my fertilizer budget. Some savings came from simply applying less but the biggest savings came from switching over to simple soluble source nutrients. If I am able to get away with the GSS suggested fertility program next year the cost of the soil tests will be higher than the cost of fertilizer for my putting greens! In future years I will expect this to rise as the nutrient reserves in the soil are depleted and I am forced to apply a more complete fertilizer program.

I have also taken into account the total time I spend applying fertilizer. Overall I have managed to keep the amount of time constant even though I am not making much more fertilizer applications. I have managed to do this with experience, and modern sprayer technology. 2012 was a year of big changes and experimentation for me. I also had a small pull behind sprayer that made every application a time consuming and laborious process.


Going forward I can now say with confidence that my fertilizer practices are as sustainable as I can possibly get them. I am not applying any fertilizer that isn't required and the conditions on the course have only improved. I really hope that more people will consider the GSS for their soil testing needs as it really helps add to the database and helps refine and redefine what sustainable fertilizer practices really are.

If anyone else has taken part in the GSS or has similar results to share please feel free to leave a comment below or join the discussion with me on twitter @Pendersuper

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