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Context: Tagasaste (Cytisus proliferus), a fast-growing leguminous tree, has potential to supplement pasture production in steep-hill country and to increase pasture resilience. Aims: In the companion paper, we quantified tagasaste production characteristics. Here, we determine the effect of proximity of 10-year-old tagasaste trees on productivity of eight pasture species including grasses (perennial ryegrass, Lolium perenne ; cocksfoot, Dactylis glomerata ; prairie grass, Bromus willdenowii ; microlaena, Microlaena stipoides), perennial legumes (white clover, Trifolium repens ; red clover, T. pratense ; lotus, Lotus pedunculatus), and an annual legume (subterranean clover, T. subterraneum). Methods: A site was established in the East Coast region of the North Island of New Zealand on steep-hill country (>20° slope). Herbage production, nutritive value and survival of pasture species established as spaced transplants were measured over 3 years. Results: Cocksfoot had high survival, herbage production and metabolisable energy content but was negatively affected by proximity to tagasaste. Microlaena was not significantly affected by proximity to tagasaste; however, it was much less productive and had lower nutritive values than the other grasses. Only 40% of perennial ryegrass transplants survived 3 years, and survival of perennial legumes was negligible. Subterranean clover was able to set seed in the open and in shade. Conclusions: Cocksfoot was the most productive grass species, and microlaena was least affected by proximity to tagasaste. Given the poor persistence of perennial clovers, annual clovers may be better suited to a tagasaste silvopasture on steep, dry hillsides. Implications: Mixtures of cocksfoot and subterranean clover may be well suited to summer-dry hillsides, between and under trees in a tagasaste silvopasture. Microlaena may provide some forage and can maintain groundcover despite shade. Growth and survival of eight pasture species in proximity to the forage shrub tagasaste were quantified in drought-prone hill country. Cocksfoot and subterranean clover were highly productive only in lightly shaded areas, whereas microlaena, although less productive than other grasses, was not significantly affected by shade treatment, and perennial legumes showed negligible survival. Cocksfoot and subterranean clover could be established between trees in a tagasaste silvopasture, with naturalised microlaena maintained beneath the canopy to provide groundcover. [ABSTRACT FROM AUTHOR]

Perennial ryegrass (Lolium perenne L.) is a widely sown pasture species in temperate regions. Under heat and moisture-deficit stress, its production is suppressed and tiller mortality increases, particularly when plants are simultaneously exposed to other stresses such as intense defoliation. We investigated the effects of extended grazing exclusion periods in spring and summer on herbage and soils of rotationally grazed, perennial ryegrass-dominant pastures at a summer-wet site and a summer-dry site in sheep and beef hill country in New Zealand. Treatments comprised 'grazed' (conventional rotational grazing), 'early opening' (grazing exclusion from mid-spring to mid-summer to allow perennial ryegrass to flower), and 'deferred grazing' (grazing exclusion from mid-spring to late summer to allow perennial ryegrass to flower and set seed). At both sites, deferred grazing increased perennial ryegrass tiller density and total vegetation cover, and reduced the abundance of broadleaf species and Pseudopithomyces chartarum spores for up to 15 months after exclusion compared with the grazed control. Herbage production was reduced during the deferred period but there was a growth surge thereafter so that herbage production over the study period was similar in the deferred and grazed treatments. Pasture nutritive values were lower in the deferred than the grazed treatment during the exclusion period but were similar in all treatments by the end of the following winter. In the autumn after deferring, seedlings contributed ~50% of the perennial ryegrass tillers present at the summer-dry site but only ~10% at the summer-wet site, where regrowth tillering of existing plants contributed a high proportion of the perennial ryegrass tillers present. Overall, early opening had few effects on the pasture, whereas deferred grazing had numerous positive effects on the pasture but only short-term effects on soil quality. We investigated the impacts of deferred grazing (livestock excluded from mid-spring to late summer to enable perennial ryegrass to flower and set seed), early opening (livestock excluded from mid-spring to early summer to enable perennial ryegrass to flower) and standard rotational grazing on hill country pastures and soils under beef and sheep grazing. Compared with standard rotational grazing, deferred grazing had positive effects on pasture productivity but only short-term effects on soil quality, whereas early opening had few effects on the pastures or soils. [ABSTRACT FROM AUTHOR]