Cultural and Chemical Controls of Thatch and Their Influence on Rootzone Nutrients in a Bentgrass Green

Abstract

Thatch accumulation is a serious problem in densely grown turfgrass maintained under low mowing heights. Opinions differ concerning effectiveness of cultural and chemical controls of thatch. The objectives of these studies were to determine the effectiveness of mechanical and chemical treatments in controlling thatch and their influence on soil nutrient retention and pH in a creeping bentgrass (Agrostis palustris Huds.) green growing on a U.S. Golf Association (USGA) rootzone. Thatch control treatments were vertical mowing (VM 4 and 8x/yr), coring (core 4x/yr), wetting agent (Wet Ag 7x/ yr), extra K (4x/yr), lime (L 4x/yr) and various combinations, and interactions of these with topdressing (Tpd 3 and 6x/yr). Rootzone nutrients determined were Ca, K, and P and rootzone pH levels were determined. Thatch measurements were determined with a rapid surface sod compression instrument termed the Thatchmeter II. Treatments and measurements were conducted for 6 yr with results reported for the last 3 yr. Lowest non-significant levels of thatch resulted following VM 4x or 8x/yr and VM + coring. Tpd 3x or 6x/yr also effectively prevented thatch buildup. When combining mechanical and chemical methods with Tpd, lowest non-significant levels of thatch resulted following VM 4x or 8x/yr, VM + coring, and VM + L, all combined with Tpd 6x/yr. Extra K (VM + K + L, K + L, K) and Wet Ag resulted in increased thatch. Lime did not influence thatch depth. Loss of rootzone K was 94% and increased with mechanical and chemical treatments. Loss of rootzone P was 86% but extra K and L treatments reduced P loss, especially under pH 7.3 following L treatments. Loss of rootzone Ca was 56% but L and extra K treatments under pH 7.3 reduced this loss.

Evaluation of core cultivation practices to reduce ecological risk of pesticides in runoff from Agrostis palustris

“…Golf course fairways and greens are often managed with core cultivation during the spring or fall to control thatch, alleviate surface compaction, enhance water infiltration, and stimulate root and shoot growth [9][10][11][12][13][14]. Although a limited amount of thatch is beneficial to lessen weed invasion, moderate soil temperatures, and enhance turf durability, an excessive thatch mat can reduce water infiltration and hydraulic conductivity, increase disease and pest pressure, and reduce cold temperature tolerance [11,13,[15][16][17].…”

Characterization, Development, and Management of Organic Matter in Turfgrass Systems

“…Numerous authors have reported thatch-mat thickness data (White and Dickens, 1984;Berndt et al, 1990;Callahan et al, 1997Callahan et al, , 1998McCarty et al, 2005McCarty et al, , 2007Barton et al, 2009;Fu et al, 2009). Measurements have been made on uncompressed thatch (Callahan et al, 1997;McCarty et al, 2007;Berndt, 2008;Fu et al, 2009) and compressed thatch (White and Dickens, 1984;Mancino et al, 1993;Callahan et al, 1997Callahan et al, , 1998.…”

“…Measurements have been made on uncompressed thatch (Callahan et al, 1997;McCarty et al, 2007;Berndt, 2008;Fu et al, 2009) and compressed thatch (White and Dickens, 1984;Mancino et al, 1993;Callahan et al, 1997Callahan et al, , 1998. Berndt (2008) reported that the uncompressed thickness of hybrid bermudagrass thatch-mat from Tifdwarf and TifEagle pu ing greens averaged 32 mm.…”

“…Berndt (2008) reported that the uncompressed thickness of hybrid bermudagrass thatch-mat from Tifdwarf and TifEagle pu ing greens averaged 32 mm. Callahan et al (1998) reported compressed thickness of thatch-mat from a 'Penncross' creeping bentgrass green ranged from 4.70 to 8.29 mm. Variation in the thickness of the thatch-mat layer has been observed among turfgrass types, management regimes, regions, and methods of measurement.…”

Efficacy of Management Practices to Mitigate the Off-Site Movement and Ecological Risk of Pesticides Transported with Runoff from Agricultural and Turf Systems

“…A cultivation method widely accepted by vegetable growers is the use of Fairways comprise approximately one-third of the managed turf of a typcial golf course (Watson et al, 1992;Lyman et al, 2007), which may be adjacent to surface waters such as streams, ponds and lakes. Golf course fairways and greens are often managed with core cultivation during the spring or fall to control thatch, stimulate root and shoot growth, alleviate surface compaction, and enhance water infiltration (Beard, 1973;White & Dickens, 1984;Turgeon, 1985;Carrow et al, 1987;Dunn et al, 1995, Callahan et al, 1998. Solid tine core cultivation requires a reduced amount of labor and is less disruptive to the surface of the turf but is believed to cause localized compaction.…”