Pasture establishment on non-cultivable hill country

Abstract

To determine the best method of pasture establishment on non-cultivable hill country (>20o slope), four treatments were compared in one year on north and south aspects at four sites with contrasting climates and soil types. Sites were located in Waikato (1), Hawke's Bay (2) and Canterbury (1). The treatments included seed mix (grasses, legumes and herbs (GLH); legumes only (LEG)) and sowing time (spring; autumn). Six weeks after sowing, seedling establishment, as a percentage of viable seeds sown, was: i) greater on south than north aspects for perennial ryegrass (31% vs 18%) and birdsfoot trefoil (5% vs 4%); ii) greater for total sown species (14% vs 8%), subterranean clover (7% vs 4%) and red clover (25% vs 14%) in the GLH than LEG mix, but greater for white clover in the LEG than GLH mix (17% vs 8%); iii) greater in autumn than spring for perennial ryegrass (36% vs 13%) and total sown grasses (22% vs 9%) but greater in spring than autumn for lotus (6% vs 3%). Plantain established well in spring in summer-wet environments, while in summer-dry environments establishment was greater in autumn. Broadcasting seed on south aspects during autumn is likely to result in the highest establishment of sown grasses and legumes, but not necessarily of herbs. The trials were conducted in an unusually wet season. Repeating a subset of the treatments at these sites will provide a greater understanding of responses to climatic variation. Keywords: pasture renewal; pasture establishment; pasture mixtures; oversowing.

High spatial variation in population size and symbiotic performance of Rhizobium leguminosarum bv. trifolii with white clover in New Zealand pasture soils

“…If these areas are not supplied with sufficient rhizobia, variable or poor establishment and performance of legumes may result. Given the fundamental importance of legume and BNF in pastoral farming systems [ 4 ], and difficulties experienced in legume establishment in hill country soils [ 5 ], ensuring legumes are matched with an effective nodule-forming and nitrogen fixing (nod +/ nif + ) strain is important. As the cost of accurately mapping populations in soils is high, and given that high variability in effective populations is expressed at field level, a precautionary approach is to supply rhizobia where clover is being sown.…”

“…Constraints can include hostile soil conditions (e.g. pH, high Al 3+ content, P-infertility), adverse climatic conditions (soil moisture deficit, extremes of temperature), through to pests, diseases, and weeds (see review by Tozer et al 2013 [ 5 ] and references therein). In many cases, these can be addressed through careful selection of legume species that match the soil and environmental conditions, and effective management of the farming system such as timing of over-sowing and controlling of grazing pressure [ 5 ].…”

“…pH, high Al 3+ content, P-infertility), adverse climatic conditions (soil moisture deficit, extremes of temperature), through to pests, diseases, and weeds (see review by Tozer et al 2013 [ 5 ] and references therein). In many cases, these can be addressed through careful selection of legume species that match the soil and environmental conditions, and effective management of the farming system such as timing of over-sowing and controlling of grazing pressure [ 5 ]. However, the success of legumes in agricultural systems is also affected by the availability of sufficient population sizes of nodule-forming (nod + ) and nitrogen-fixing (fix + ) rhizobia in soils [ 6 , 7 ].…”

Resiembra natural de plántulas de Plantago lanceolata cv. ‘Ceres Tonic’ en una pradera establecida

“…The removal of a high post-grazing canopy provided a layer of dead litter in the base of the sward and may, therefore, have created a more suitable environment for the establishment of seedlings. Similarly, Tozer et al (2016) found the presence of litter (dead vegetation) enhanced seedling establishment of broadcast grass, herb, and legume seed by over 3-fold. Furthermore, Hamre et al (2010) observed mulching (mowing once a year then leaving the hay in situ after cutting) had a positive effect on the plant density of plantain in semi-naturalised grassland.…”

Quantifying the value proposition for white clover persistence on a New Zealand summer-dry hill-country farm

“…It had declined by the following autumn (March 2017) to 14% but in autumn 2019 and 2020 was 17-18%. The introduction of additional white clover on a single south-facing slope at Tangihanga was successful in the short term as a result of using well-recognised techniques: seasonal timing in terms of reliable soil moisture content and sufficiently warm temperature conditions; control of cover via grazing management and herbicide prior to over-sowing; and with good seed-soil contact via stock trampling (Tozer & Douglas 2016). The challenge appears to be retaining the established plants in the sward over the longer term , where they are subject to selective grazing, competition from well adapted grass species and seasonal variation in soil temperature and moisture (Wedderburn et al 1996).…”