Early or delayed sowing for improved ryegrass control?


Research organisaton
Funding source

Trial details

Researcher(s) Sarah Noack, Peter Hooper (Hart Field Site Group), Chris Preston and Sam Kleemann (Univeristy of Adelaide)
Year(s) 2015
Contributor Hart Field Site Group
Trial location(s) Site 5, Hart, SA
Early or delayed sowing for improved ryegrass control? locations

To investigate the effect of early or delayed sowing on reduction of ryegrass numbers in combination with different preemergent herbicides.

Key messages
  • The early break to the 2015 season meant soil moisture and rainfall conditions were similar between ToS 1 and 2 and there was little variation in annual ryegrass control among preemergent herbicides tested.
  • Grain yield and quality were not affected by pre-emergent herbicide; however, there was a 0.7 t/ha yield penalty for the later ToS.
  • Over two seasons of research ryegrass seed set was greater when sowing was delayed.
Lead research organisation Hart Field Site Group
Host research organisation Hart Field Site Group
Trial funding source GRDC
Related program N/A

The financial assistance of GRDC to undertake this research is gratefully acknowledged.


Other trial partners University of Adelaide
Download the trial report to view additional trial information


Crop type Wheat
Treatment type(s)
  • Herbicide
  • Herbicide: Type
  • Sowing
  • Sowing: Timing
Trial type Experimental
Trial design Randomised,Replicated,Blocked

Hart 2015

Sow rate or Target density Estoc wheat @ 80 kg/ha
Sow date 30 April 2015
Harvest date Not specified
Plot size 1.75m x 10m
Plot replication Not specified
  • DAP (18:20) + 2% Zn @ 100 kg/ha
Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

@T1: ToS 1 (30-12-2014) @T2: ToS 2 (27-05-2015)
# Treatment 1
Ryegrass density (plants/m2) Ryegrass density (plants/m2)
1 Nil 18 6
1 IBS Boxer Gold 3 1
2 IBS Sakura 1 2
2 Triflualin + triallate 2 2
3 IBS Sakura + IBS triallate 0 1
3 IBS Boxer GOld + POST Boxer Gold 1 2

Ryegrass density plants/m2

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Site 5, Hart, SA Not specified
Derived trial site soil information
Australian Soil Classification Source
Trial site Soil order
Site 5, Hart, SA Chromosol
National soil grid Source
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties



Derived climate information

No observed climate data available for this trial.
Derived climate data is determined from trial site location and national weather sources.

Site 5, Hart SA


Some data on this site is sourced from the Bureau of Meteorology

SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.

Trial last modified: 06-06-2019 15:37pm AEST