Asking the right questions

Here’s another interesting article I came across recently. Dr. Carrow wrote an article in the October 1993 issue of GCM with the title Eight questions to ask: evaluating soil and turf conditioners. The article is about products, and deciding if they are required. It includes plenty of examples.

The very first question, Dr. Carrow wrote, should be “Is this product needed in my situation?” He uses the example of humic acid.

“Turfgrass growing in a soil, for example, produces organic matter, which decomposes to produce ‘natural’ humus and humic acids. A soil with just 1% organic matter content within the surface 8 inches [20 cm] would have 13,300 lbs. of organic matter per acre [14,920 kg/ha] on a dry weight basis with most of this as humus …

With a growing turfgrass and clippings returned, 2,000 lbs of crop residue (shoots plus roots) can easily be produced [per acre], which would decay to approximately one-third humus, or 660 lbs of new humus added each year to replace any lost humus. In addition, a half-inch thatch layer would contribute 28,000 lbs of organic matter per acre with one-third to one-half as potentially humus in nature. Thus, 16,000 lbs per acre of humus [17,950 kg/ha], consisting of about 50 to 70 percent humic acid, may be present in a typical turfgrass soil from ‘natural’ means.”

He doesn’t say humic acid is not required, but the example shows that with so much humic acid already in the soil, asking the question “is this product needed in my situation?” allows the turfgrass manager to come up with their own answer.

Here are the 8 questions to ask.

  1. Is the product needed in my situation?

  2. Are independent test results available?

  3. What is the magnitude of the response?

  4. Does this product provide consistent results?

  5. What is the duration of the response?

  6. Are there better alternatives?

  7. Do benefits justify costs?

  8. Should I try this product on a trial area?

I suggest reading the entire article for more examples.

Micah Woods
Micah Woods

Scientist, author, consultant, and founder of the Asian Turfgrass Center