REFERENCE SUFFICIENCY RANGES
TURF AND LAWN GRASSES

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Bentgrass

C. R. Campbell and C. Owen Plank

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• Critical Values

  None established.

• Sampling Procedures

  A representative sample of clippings from a freshly mowed green is the best indicator of nutritional status. A double handful of clippings is an adequate sample. In as much as possible, the sample should be taken when clippings are free of foreign matter, including sand, pine straw, etc.

  Samples containing significant amounts of foreign matter should be processed by the following procedure.

  1. Sand
     To remove sand and heavy foreign matter, pour the sample into a 1000-mL beaker containing distilled water. The bentgrass and lighter materials float to the surface. Stir and remove quickly to avoid leaching water-soluble nutrients. Blot dry and place in dryer.

  2. Light-weight foreign matter
     After the sample is dry, sieve the sample on a 1-mm screen (No. 18 U.S. Testing Sieve). The bentgrass falls through the screen while other light-weight particles are retained for removal.

  For problem samples, a matching sample from a "good" green should be taken for comparison.

  Monitoring to fine tune fertility programs and/or maintain records of environmental stewardship is done by sampling greens monthly. Sampling should follow the same management sequence monthly to improve usefulness of the data over time.

  Samples are loosely packed and shipped to the laboratory in paper containers.

• Sufficiency Ranges
  
  
  • Clippings from Recently Mowed Green
    
    

    Macronutrients
    N	P	K	Ca	Mg	S
    4.0–5.0%	0.3–0.6%	2.2–3.5%	0.25–0.75%	0.2–0.4%	0.2–1.0%

    
    

    Micronutrients
    Fe	Mn	Zn	Cu	B
    50–300 ppm	25–300 ppm	20–70 ppm	5–15 ppm	3–20 ppm

    
    

    Important Ratios

    The N:S ratio should be 10 to 15. Ratios over 18 indicate a sulfur deficiency. The N:K ratio should be 1.2 to 2.2.

• DRIS Norms

  DRIS norms have not been reported for bentgrass.

• Remarks

  Sufficiency ranges are based on available literature and experience reviewing analytical results.

• References

  Mills HA, Jones JB Jr. 1996. Plant analysis handbook II: a practical sampling, preparation, analysis, and interpretation guide. Athens (GA): Micro-Macro Publishing.

Electronic Document Prepared by:
Catherine Stokes, Communication Specialist
Agronomic Division of the N.C. Department of Agriculture and Consumer Services. July 2000.