A comparison of three contrasting farming systems on forage production and soil characteristics over three years

Abstract

There has been considerable interest in regenerative agriculture and the potential impact of diverse forage mixes and grazing to higher residuals on pasture production and soil quality. This study aimed to evaluate the forage productivity, botanical composition, and soil characteristics of three different forage mixtures managed as per best practise for each forage type over three years in a summer-dry environment. The three treatments were A: ryegrass/clover (4 species) rotationally grazed by lambs in winter/spring and yearling cattle in late spring/summer; B: a hyperdiverse mix (23 species) grazed by cattle with daily shifts; and C: plantain/clover/chicory (7 species) rotationally grazed by weaned lambs in winter, and ewes and lambs in spring. Over three years the hyperdiverse mix produced significantly less dry matter than the ryegrass and plantain mixtures (29246, 36709 and 32743 kg DM/ha respectively P<0.001). Thirty months
after sowing the number of species present had declined to nine, three and four in the hyper-diverse, ryegrass and plantain pastures respectively. There was no effect of farming system on soil carbon, earth worm number or organic matter disappearance. Water infiltration rate was significantly slower on the hyper-diverse treatment, potentially due to the effect of cattle treading. Three years after sowing, the use of a hyper-diverse forage system provided no advantage for forage production or soil health over sowing a plantain or ryegrass mix.