Green couch (Cynodon dactylon) varieties have been used on elite and community sports fields as a standalone species or within combination swards, oversown with ryegrass (Lolium spp.) for decades. Over the past few years’ choice of green couches has expanded significantly; most notably Plant Breeder’s Rights (PBR) and or trademarked varieties.
Some new and improved varieties have superior wear tolerance, which can be attributed to high lignin production and thatch production. Thatch is largely misunderstood by the majority of turfgrass managers. Fundamentally people believe that all thatch is bad and it should be removed. However, thatch is a normal component of actively growing turfgrass and beneficial levels of thatch can actually increase the resilience of the turf to heavy traffic (e.g. sports field usage).
A twelve week study, commencing 30 July 2013, was commissioned to investigate the performance of various oversowing techniques currently used by curators of elite sports stadiums.
Turfgrass varieties
- Cynodon dactylon (green couch) variety OZ TUFF®; and
- Lolium spp. (ryegrass) mix ‘Striker Stadium’ from Nuturf®. This is a mixture of Fiesta 4, Barlennium and Top Hat which is the preferred ryegrass mix for Stadiums Queensland venues.
Trial Setup
A randomized complete block design containing three (3) replications will be adopted to include the following factors. (i) ryegrass oversown using the drill seeder only at 500 kg/ha rate; (ii) verticutting then oversowing using the drill seeder at 500 kg/ha rate; (iii) ryegrass oversown using the drop spreader only at 500 kg/ha rate; (iv) verticutting then oversowing using the drop spreader at 500 kg/ha rate; and (v) a control plot. Findings from TU10015 identified that Australian sports turf practitioners of elite venues initially apply between 300-600kg/ha of ryegrass when oversowing into green couch. The mean value was 500kg/ha which was adopted for this particular study.
Plots were setup at Australian Lawn Concepts Cunungra farm 30 April 2013
ASTC Director Matt Roche applying one treatment of ryegrass seeding using a drop spreader.