1998 Iowa Turfgrass Research Report

1998 Iowa Turfgrass Research Report

Modifying Athletic Field Soils with Calcined Clay and Tillage

David D. Minner and Jeffrey J. Salmond

The objective of this study was to evaluate calcined clay in a tilling renovation process and its effects on turfgrass growth.

A study was initiated in November 1997 at an Ames High School football practice field in Ames, Iowa, to evaluate calcined clay (Turface^® MVP) in a tilled renovation procedure. The study was conducted on a separate irrigated practice field (different from the calcined clay topdressing study). The 15,750 sq.ft. experimental plot area was arranged between the hash marks and the goal lines. Each individual plot measured 15 ft. by 50 ft., and was centered on every yard line marker (goal line, 5, 10, 15, 20, etc.) (Table 1) such that 7.5 ft. was on one side of the yard line and 7.5 ft. was on the other side of the same yard line. Treatments consisted of calcined clay at 1 ton/1000 sq.ft., calcined clay at 2 tons/1000 sq.ft., and an untreated control (Table 2). Treatments were completely randomized and replicated seven times. Each replication was 45 ft. by 50 ft. with three treatments. Treatments were topdressed at their respective rate and tilled into the top 4 inches of soil with a Rotadairon (Bryan Wood, Commercial Turf & Tractor). The Rotadairon is used to level a playing surface and prepares the seed bed while burying roots, rocks, clods, clumps, or grass. The untreated control contained no amendment and was tilled. The total plot area will be seeded in spring 1998 with a bluegrass blend containing 'Nublue', 'Limousine', and 'Touchdown'.

The control will be topdressed with sand in 1998 and the calcined clay-amended plots will be topdressed with Turface^® MVP.

Table 1. Experimental plot layout of calcined clay tilled renovation. Treatments were applied on November 13, 1997.

	[Center of field]	Plot #
Goal Line	________3________	1	Plot size is 50 x 15 ft
	1	2	REP 1
	2	3
	1	4	Plots are centered Between hash marks
	3	5	REP 2
	2	6
	3	7	Each 5-yard line is the Center of the plot
	1	8	REP 3
	2	9
	1	10
50-yd Line	________2________	11	REP 4
	3	12
	1	13
	2	14	REP 5
	3	15
	1	16
	3	17	REP 6
	2	18
	3	19
	2	20	REP 7
Goal Line	________1________	21

Table 2. Treatment listing and respective rates.

	Treatment	Rate (tons/1000 ft2)
1	Turface	1
2	Turface	2
3	Untreated control*	NA

Turface applied to plots with topdresser and then tilled with Rotadairon to 4-inch depth.

*Untreated control received no amendment but was tilled with the Rotadairon.

ISU Horticulture:Publications:1998 Turfgrass Report

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