Early or delayed sowing for ryegrass control?


Research organisaton
Funding source

Trial details

Researcher(s) Sarah Noack and Peter Hooper (Hart Field Site Group), Chris Preston and Sam Kleemann (University of Adelaide)
Year(s) 2014
Contributor Hart Field Site Group
Trial location(s) Site 5, Hart, SA
Early or delayed sowing for ryegrass control? locations

To investigate the effect of early or delayed sowing on reduction of ryegrass numbers in combination with different pre-emergent herbicides

Key messages

The early break to the 2014 season meant soil moisture and rainfall conditions were similar between ToS 1 and 2 and there was little variation in annual ryegrass control among pre-emergent herbicides tested. Grain yield and quality were not affected by pre-emergent herbicide however, there was a 1.22 t/ha yield penalty for the later ToS

Lead research organisation Hart Field Site Group
Host research organisation Hart Field Site Group
Trial funding source GRDC UA00149
Related program N/A

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

Other trial partners Not specified
Download the trial report to view additional trial information


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

Hart 2014

Sow rate or Target density Seed sown @ 80kg/ha
Sow date 4 May 2014 4 May, 2 June 2014
Harvest date Not specified
Plot size 1.75m x 10m
Plot replication 3

Seeding: 80kg/ha DAP, 8/7/14: 95L/ha UAN, 15/8/14: 100L/ha UAN

Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

@T1: ToS 1 (04-05-2014) @T2: ToS 2 (02-06-2014)
# Treatment 1
Screenings (%) Test weight (kg/hL) Protein (%) Grain yield (t/ha) Ryegrass density (plants/m2) Ryegrass heads (heads/m2) Ryegrass density (plants/m2) Ryegrass heads (heads/m2)
1 Sown 4 May 3 81.6 10.2 4.15
2 Sown 2 June 3 81.5 11.4 2.93
3 Untreated control 59 350 77 164
3 IBS Boxer Gold @ 2.5L/ha 21 74 12 35
4 IBS Sakura @ 118g/ha 8 39 8 41
4 IBS Boxer Gold @ 2.0L/ha + triallate @ 2.0L/ha 6 20 12 36
5 IBS Sakura @ 118g/ha + triallate @ 2.0L/ha 3 32 3 9
5 IBS Boxer Gold @ 2.0L/ha + POST Boxer Gold @ 1.5L/ha 8 71 6 14

Grain yield t/ha


Protein %


Ryegrass density plants/m2


Ryegrass heads heads/m2


Screenings %


Test weight kg/hL

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Site 5, Hart, SA Calcarosol
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



Site 5, Hart SA 2014

Observed climate information

Rainfall trial gsr (mm) 280mm

Derived climate information

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 15:07pm AEST