Thatch and Mat Management in an Established Creeping Bentgrass Golf Green

Abstract

Thatch is a layer of partially decomposed organic matter between green shoot tissue and the soil surface, and mat is thatch partially intermixed with topsoil. Excessive thatch-mat layering (.2.54 cm) is generally detrimental to turfgrass management, and numerous techniques including various mechanical and topdressing regimes, have been attempted to reduce its severity. This factorial experiment investigated the effectiveness of combining mechanical-biological and topdressing treatments for controlling thatch-mat levels in an established USGA-specified golf green planted with 'A-1' creeping bentgrass [Agrostis stoloniferous L. var. palustris (Huds.)]. Two levels of topdressing were used, and the mechanical-biological treatments included vertical mowing at two different depths and timings, core cultivation, grooming, a biological granular supplement (Thatch-X), and combinations of core cultivation with grooming and/or vertical mowing. Differences among the mechanical-biological treatments were detected following 2 consecutive yearly applications. Thatch-mat depth (mm) was 12 to 15% greater for Thatch-X and topdressing alone compared with other treatments. Organic matter content (g kg 21 ) increased 32% for the untreated and decreased 19% for core cultivation combined with vertical mowing and grooming, whereas all other treatments maintained pre-study levels. Compared with the untreated, surface hardness was reduced |9% for all treatments using core cultivation, while water infiltration rates increased 127 to 168%. Vertical mowing treatments improved water infiltration rates by 40 to 65%. Turfgrass quality was not greatly impacted by the mechanicalbiological treatments as ratings ranged from 8.4 to 10.0. However, mower scalping and dry spots contributed to unacceptable or only marginally acceptable turfgrass quality (6.4-7.2) for the untreated by the end of the study. Compared with topdressing alone, ball roll distance was decreased 6% by vertical mowing 7 days after treatment (DAT) and 5 to 8% by core cultivation up to 14 DAT. Sand topdressing alone was insufficient for managing thatch-mat levels in an established creeping bentgrass golf green.

Creeping Bentgrass Color and Quality, Chlorophyll Content, and Thatch–Mat Accumulation Responses to Summer Coring

“…Spring-plus-summer coring resulted in increased chlorophyll levels as well as improved turf color and quality in late summer. Eggens, 1980;White and Dickens, 1984;Murphy et al, 1993;McCarty et al, 2005McCarty et al, , 2007. Murray and Juska (1977) observed that coring reduced total organic matter in the thatch of Kentucky bluegrass (Poa pratensis L.), but the eff ect was short-lived.…”

“…× C. transvaalensis (Burtt Davy)]. The most extensive coring studies in creeping bentgrass were reported by McCarty et al (2005McCarty et al ( , 2007 and Murphy et al (1993). Murphy et al (1993) investigated the eff ects of hollow-and solid-tine coring on thatch-mat in a 'Penneagle' creeping bentgrass green.…”

“…Hereafter, this organic layer will be referred to as thatch-mat. Excessive thatch-mat layers can have numerous negative eff ects on turfgrasses as outlined by McCarty et al (2005McCarty et al ( , 2007. In addition, creeping bentgrass stems and roots become elevated in thick surface organic layers, and plants can be rendered more susceptible to injury from summer stresses and disease (Dernoeden, 2002;Turgeon, 2008).…”

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

“…We speculate the greatest difference in soil physical properties was most prominent shortly after hollow tine or solid tine core cultivation; which diminished as roots grew, compaction dissipated, and core channels were covered or filled. Other researchers have reported greater air porosity and saturated water conductivity in turf managed with hollow tines compared to solid tines, and enhanced water infiltration in turf managed with hollow tine core cultivation compare to untreated turf (Murphy et al, 1992;Baldwin et al, 2006;McCarty et al, 2007).…”

“…As a result one would anticipate increased soil compaction with the solid tine cultivation and greater accessibility of soil adsorptive sites with the hollow tine cultivation. This would influence infiltration and hydraulic conductivity (Murphy et al, 1992;Baldwin et al, 2006;McCarty et al, 2007) as well as pesticide availability for transport (Liu et al, 1995;Gardner et al, 2000;Raturi et al, 2005). Analysis of pesticide loads with runoff volumes and pesticide concentrations in the runoff showed loads were attributed to runoff volume more than chemical concentrations for both management practices (volume r 2 = 0.78 to 0.90, concentration r 2 = 0.05 to 0.22).…”