Dr. Katherine Tozer

Senior Scientist - Farm Systems

E: Katherine.Tozer@agresearch.co.nz


B. Ag. Sci. (University of Melbourne)
Masters Ag. Sci. (University of Melbourne)
PhD (University of Melbourne)

Research interests & activities

Undertaking and managing research related to pasture establishment and persistence in dairy, and sheep and beef pastures. This includes research on:
  • morphological traits associated with persistence.
  • impact of abiotic and biotic stresses on ryegrass growth.
  • pasture establishment methods in non-cultivatable hill country.
  • ecology and management of summer-active grasses in North Island dairy pastures.
I have also been involved in developing AgPest, a website to disseminate independent information on the impact, biology and control  of key pasture weeds and pests. www.agpest.co.nz.

Professional Memberships

  • New Zealand Grassland Association
  • New Zealand Plant Protection Society


Tozer KN, Cameron CA, Matthews L 2015. Grazing defoliation and nutritive value of Setaria pumila and Digitaria sanguinalis in Lolium perenne-based swards. Crop and Pasture Science 66: 184-191.

Tozer KN, Chapman DF, Bell NL, Crush JR, King WM, Rennie GM, Wilson DJ, Mapp NR, Rossi L, Aalders LT, Cameron CA 2014. Botanical survey of perennial ryegrass-based dairy pastures in three regions of New Zealand: implications for ryegrass persistence. New Zealand Journal of Agricultural Research 57: 1-16.

Tozer KN, Marshall AJ, Cameron CA, Edwards GR 2013. Salt (NaCl) application as a tool to reduce the annual grass weed, ripgut brome, in New Zealand South Island hill/high country pastures. New Zealand Journal of Agricultural Research 56: 117-129.

Tozer KN, Minneé EMK, Cameron CA 2012. Resistance of New Zealand dairy pastures to ingress of summer-active annual grass weeds. Crop and Pasture Science 63: 1026 -1033.

Tozer KN, Cameron CA, Thom ER 2011. Weed ingress and pasture persistence in Bay of Plenty dairy farms: field observations and farmer perceptions New Zealand Plant Protection 64: 68-74.

Tozer KN, Barker GM, Cameron CA, James TK 2010. Relationship between seedbank and above-ground botanical composition during spring. New Zealand Plant Protection 63: 90-95.

Tozer KN, Chapman DF, Cousens RD, Quigley PE, Dowling PM, Kearney GA, Cameron CA 2009. Effects of perennial species on the demography of annual grass weeds in pastures subject to seasonal drought and grazing. Crop and Pasture Science 60: 1088–1096.

Tozer KN, Chapman DF, Quigley PE, Dowling PM, Cousens RD, Kearney GA, Sedcole JR 2008. Controlling invasive annual grasses in grazed pastures: population dynamics and critical gap sizes. Journal of Applied Ecology 45: 1152–1159.