The effect of different densities of tussocks (Festuca novae-zelandiae, Poa laevis) in short tussock grassland associations was studied using transplanted cocksfoot (Dactylis glomerate) seedlings as indicators of inter-tussock plant growth. The dense tussock associations considerably modified the microclimate, reduced frost damage and initially promoted cocksfoot growth. Sparse tussock associations did not generally promote cocksfoot growth unless plants were near the tussock base and sheltered from the prevailing wind
The effect of protection from sheep grazing on indigenous plant species in relatively mesic, strongly modified Poa cita grassland, was examined using paired grazed and ungrazed sites. Ungrazed sites, fenced at times ranging from four to more than 24 years ago, had fewer species, lower indigenous cover and lower tussock density than adjacent grazed sites. The dominance of adventive species, particularly cocksfoot (Dactylis glomerata), in ungrazed sites appeared to be important to these differences.