Summary
The broad objective of DAN 082 was to develop and promote Lotus technology in New South Wales. Specific objectives were as follows:- Experimental objective: To determine if grazing intensity and strategic spelling affects expression of the adaptive characteristics of Greater lotus and birdsfoot trefoil and to examine whether the level of grass competition interacts with the response to grazing intensity and strategic spelling.
Industry objective:
(a) To define grazing management strategies that enable Greater lotus and birdsfoot trefoil to maintain at least 30% of total pasture dry matter in a mixed grass/ legume pasture, for at least 4 years in beef breeding system
(b) To demonstrate the use, management and economic benefit of Greater lotus and birdsfoot trefoil cultivars to grow out steers in conjunction with graziers, seed companies, extension officers and other stakeholders through a series of colearning sites.
These project objectives required a methodology that combines field research to develop sound grazing management practices for Lotus persistence, with technology transfer work to promote increased use of Lotus based pastures. The R&D process implemented to achieve this comprised a research phase (the core experiment with sites in each target region north coast, south coast, northern tablelands, southern tablelands), combined with an extension phase (co-learning groups and on-farm demonstrations in each of the regions involving farmers, project workers and industry stakeholders).
The core experiment was established at 4 sites (Casino, north coast; Nowra, south coast; Glen Innes, northern tablelands; Canberra, southern tablelands) to examine the effects of grazing intensity and strategic spelling on the persistence of Lotus in relation to the adaptive characteristics of each Lotus species and cultivar. Treatments at each core site were factorial combinations of grazing strategies (continuous grazing, rotational grazing, autumn spelling, summer spelling), grazing intensity (low biomass, high biomass), Lotus cultivars (GL Maku, GL Sharnae, BFT Goldie, BFT Spanish) and companion grass type (volunteer, introduced). A standard protocol was implemented to ensure uniform management practices and measurement procedures across the 4 experiment sites. The treatments were imposed for 24 - 40 months depending on site) and measurements made of Lotus establishment, botanical change, rhizome/seedbank development and seedling recruitment to determine whether the grazing treatments affected Lotus persistence.
The experimental and co-learning phases were linked where practicable by paired comparisons at the co-learning sites of key treatments from the core experiment. Seventeen co-learning sites were established on farms; 6 on the northern tablelands/slopes, 4 on the north coast, 4 on the southern tablelands, and 3 on the south coast. Activities at the colearning sites were designed to assess adaptation of the target Lotus cultivar for the district and to compare traditional grazing management with strategic grazing management for effects on Lotus persistence. For GL co-learning sites (ie. coastal), the comparison was of continuous grazing versus autumn spelling as autumn spelling was considered to be the best bet treatment to promote rhizome extension, and hence Lotus persistence. For BFT co-learning sites (ie. hinterland), the comparison was of continuous grazing versus summer spelling as summer spelling was considered to be the best bet treatment to promote prolific flowering/podding for seedbank development and seedling recruitment, and hence Lotus persistence.
