Can Lotus pedunculatus over-sowing in low-fertility tussock country increase farm resilience?

Abstract

The range of legumes to boost farm productivity in low-fertility hill country are limited. Lotus pedunculatus (Lotus) provides an option when soil pH is below 5 but is intolerant to severe and regular grazing. However, itcan be used at sites that are only grazed occasionally during spring summer and autumn. Oversowing of Lotus pedunculatus has been used to improve 17% of the total area of Avenel Station, Millers Flat. Measurements of pasture growth and animal production were collected over three years post-sowing, indicating a doubling of pasture production from the native form while providing liveweight gains of 0.135 and 0.75 kg/d in lambs and yearling cattle respectively. Systems modelling was used to re-examine the current farm-system configuration to test the possible outcomes from implementing further enterprises that may capture the increased late spring and summer production effectively. Reducing ewe numbers and concentrating on improving lamb survival were the most cost-effective and environmentally effective options. Buying in further finishing lambs to use the summer surplus also improved profitability. Increasing cow numbers was similarly profitable. Increasing ewe numbers also required an increase in winter feed supply and was the least profitable way to capture the benefits. Testing using climatic extreme scenarios demonstrated that the oversowing of Lotus on the higher, wetter tussock country increased the resilience of the farm by providing a buffer during dry summers.

Tagasaste silvopastures in steep-hill country. 2. Effect of increasing proximity to tagasaste on growth and survival of companion pasture species

“…Subterranean clover must also be grazed lightly to enable the seed production necessary for its continued regeneration (Sheath 1980; Brock et al . 2003; Stevens et al . 2020; Moss et al .…”

“…White clover, red clover and lotus can benefit from infrequent and lax defoliation during their reproductive period and during drought to enable seed production and protect the carbohydrate reserves. Subterranean clover must also be grazed lightly to enable the seed production necessary for its continued regeneration (Sheath 1980;Brock et al 2003;Stevens et al 2020;Moss et al 2022). Given the lack of persistence of legumes in our study, we suggest that a less frequent and/or less severe defoliation regime may be required to improve legume persistence.…”

A review of legume research and extension in New Zealand (1990–2022)

“…continue to be advocated for improving productivity of low pH, high aluminium soils (e.g. Stevens et al 2020) but their niche opportunity is often thwarted by inconsistent seed supply (Monk et al 2016) and difficulties of establishment in extensive high country terrain, under a predominantly set-stocked management (Berenji et al 2018). Dairy research on L. corniculatus has demonstrated increased milk yields and feed conversion efficiency compared with ryegrass and white clover pastures (Harris et al 1998) but to date the challenges of maintaining it in a dairy rotation have prevented adoption.…”

“…continue to be advocated for improving productivity of low pH, high aluminium soils (e.g. Stevens et al . 2020) but their niche opportunity is often thwarted by inconsistent seed supply (Monk et al .…”