The effects of clover and nitrogen fertiliser on the presence of pasture pests in dairy pastures


  • Alison Popay AgResearch
  • Derrick Wilson AgResearch
  • Colin Ferguson AgResearch
  • David Chapman DairyNZ
  • Julia Lee DairyNZ
  • Gerald Cosgrove AgResearch
  • David Stevens AgResearch



environmental constraints, host plants, insect nutrition, macronutrients, pest management


A comprehensive dataset obtained from sampling four trials investigating interactions between perennial ryegrass and white clover under two levels of applied nitrogen (N) has highlighted different effects of pasture composition and N use on pasture pests.
• For swards with white clover, presence of clover root weevil, whitefringed weevil and grass grub increased under low N by 36%, 11% and 5%, respectively, compared with high N treatments.
• High N increased the presence of both Argentine stem weevil and root aphid by 7%.
• Unexpectedly, clover reduced the presence of two grass feeders, Argentine stem weevil and black beetle, by 7% and 11% respectively.
• Presence of grass grub was 17-30% lower under tetraploid ryegrasses than under diploids.
• More clover and reduced N fertiliser inputs could reduce the frequency of black beetle and Argentine stem weevil with environmental benefits.






Resilient Pastures Symposium 2021