The Potential of Compost and Compost Tea on Athletic Turfgrass

Methods

Summary

           The results from this project will be collected through both direct sampling and remote sensing.  The direct measurement methods will include pre and post soil samples including the minerals, percent organic matter, and plant tissue samples all run through Clemson Extension.  Additionally, Haney and Phospholipid Fatty Acid (PLFA) tests will be done by Ward laboratories to determine the microbial biomass in the soil. Infiltration tests will be conducted within an infiltration ring and bulk density will be tested from soil cores. Both of these tests will be done on site or in Dr. Kloot’s lab on campus.  Soil testing is being done in addition to above ground turfgrass testing because the compost should largely affect the soil health and in turn promote a healthy stand of grass, so testing the soil is a major component of the research. 

            On top of these tests, remote sensing will be used as a practical method of allowing more frequent measurements to be taken without increasing the project budget.  A Trimble Greenseeker (Trimble Inc., Sunnyvale CA) will be used to calculate the normalized difference vegetation index (NDVI) of the turfgrass.  The Greenseeker will be steadied with a stand twenty-four inches above the turf to get readings at the center ten inches of each plot.  Four readings will be taken from each plot in the cardinal directions and then averaged for the NDVI of the plot.  

            Lastly, microscopy methods will be used for analysis.  Microscopy will be used to evaluate the compost to ensure that there is not a substantial presence of harmful microbes in the compost pile. Soil samples from the field will also be studied with the same methodology to see the difference in the microbial community throughout the study.  Lastly, roots from the test plots will be cleared and stained so that they can be evaluated under a microscope for arbuscular mycorrhizal fungi (AMF).

Challenges

The biggest foreseen challenge is contamination of the compost and compost tea plots with fertilizers and other chemicals.  A tarp will be use to cover the plots that do not get chemical treatments while the athletic department is out treating the field.  This is require both cooperation and communication between the department and myself.

Time and funding will also a major constraints on this experiment since there is less than a year from the proposal date to the defense and we want to keep the costs down.  For this reason, the duration of the experiment as well as the methods of data collection have been specifically chosen to fit within these parameters. 

Pre Analysis Plan

Hypotheses:

Hypothesis 1: Plots treated with compost tea will show no significant difference in plant color, vigor or biomass compared to conventionally treated plots.  

Hypothesis 2:  Plots treated with solid compost will show no significant difference in plant color, vigor or biomass compared to conventionally treated plots.  

Hypothesis 3: Plots treated with compost or compost tea will show measurable changes in belowground microbiodiversity compared to conventionally treated plots.

Hypothesis 4: Plots treated with compost or compost tea will show measurable changes in conventional soil test values (Mehlich 1, Clemson University Extension Labs) compared to conventionally treated plots.

Hypothesis 5: Plots treated with compost or compost tea will show measurable differences in bulk density and infiltration rates compared to conventionally treated plots.