Poukawa Research Station

On-farm Research, Hastings

What was achieved

  • Increased understanding of seasonal growth pattern and productivity of annual and perennial legumes in Hawkes Bay dryland.

About the study site

Poukawa Research Farm is a 290 ha dryland farm (750 mm annual rainfall) located 14 km south of Hastings. The farm operates a 50:50 sheep cattle ratio. 800 ewes are mated to a terminal ram with all lambs finished. 50 cows are mated to a wagyu bull and all stock finished. Flexibility is maintained with winter trade lambs purchased and killed at heavy weights in spring and cull dairy cows purchased in early winter and slaughtered in early summer once clean-up duties are finished. Contour ranges from flat to moderately steep with a mix of north and south facing slopes. Approximately 80% of the property is cultivatable and approximately 25 ha are used for early season dryland squash. Poukawa Research Farm is typically winter warm and summer dry with an annual rainfall of 730 ± 26.5 mm.


Study 1 - Seasonal growth pattern of annual and perennial legumes in Hawkes Bay dryland

What was trialled

  • Dry matter (DM) production and time of flowering of a range of annual (8) and perennial clovers (2) along with pure swards of annual ryegrass, perennial ryegrass, plantain and chicory were compared.
  • Ten legume species, two grass species and two herb species were each sown as pure swards.
  • Plots where managed under different cutting regimes in order to measure seasonal DM production of each species under repeated cuts versus a single end cut.

Key findings

  • In a difficult year (dry autumn 2020 and 2021) the annual clovers were comparable in terms of dry matter (~8 tonne) with perennial ryegrass and plantain.
  • Viper balansa and Woogenellup sub clover flowered early and produced the greatest amount of dry matter up to the beginning of November, however, the early flowering of these clovers may cause difficulties in enabling seed set under set stocking systems.
  • The perennial clovers (Kopu 11 white clover and Relish red clover) had higher total yields but 38% of total production occurred in summer.
  • Regular cutting produced higher total yields than a single end cut for the annual and perennial clovers with the exception of the arrowleaf cultivars.
  • Arrowleaf clover is best utilised with a single grazing late in the season.


Study 2 - Understanding the productivity and seasonality of hill country grass species in a dryland environment

What was trialled

  • The productivity and seasonality of various hill country grass species in a dryland environment in both the presence and absence of fertiliser was compared.
  • Dry matter production (DM) of a range of 6 hill country grass species (Perrenial Ryegrass, Browntop, Brome, Cocksfoot, Tall fescue, Phalaris) and 2 herb species (chicory, Plantain) with and without supplemental nitrogen fertiliser over a 3-year period was measured.
  • At the end of the trial, an analysis of species composition and dead and bare ground was undertaken.

Key findings

  • In the absence of grazing and with no fertiliser applied the ranking of total DM production was chicory > brome > Phalaris > cocksfoot > ryegrass > plantain > tall fescue > browntop.
  • Production across this trial was generally poor, particularly for the unfertilised treatments. Though, for two years of the trial (2020 and 2021) there were significant autumn and winter droughts, yet production was still within the range of DM measured at Poukawa over a 20 year period.
  • Across all species, the response to applied nitrogen was 14.6 kg DM/ha although the grasses responded better to nitrogen fertiliser than the herbs did.
  • Browntop maintained very healthy plant populations over the three years of the trial. Cocksfoot, brome and ryegrass maintained high levels of sown species and low levels of other grasses and weeds in both fertilised and unfertilised plots.
  • Plantain and chicory populations decreased over three years with a much higher proportion of other species and bare ground in the herb plots than in the grass treatments.

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