Early or delayed sowing for improved ryegrass control: summary of three seasons


Research organisaton
Funding source

Trial details

Researcher(s) Sarah Noack (Hart), Peter Hooper (Hooper Consulting) and Sam Kleemann, Chris Preston and Gurjeet Gill (UoA)
Year(s) 2016
Contributor Hart Field Site Group
Trial location(s) Site 5, Hart, SA
Early or delayed sowing for improved ryegrass control: summary of three seasons locations

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

Key messages
  • Delayed sowing provided no advantage over early sowing in reducing ryegrass plant or head number.
  • In two out of three seasons, later sown crops were lower yielding and did not provide as good crop competition allowing ryegrass head number to increase.
  • Sowing time had no effect on the performance of pre-emergent herbicides for ryegrass control.
Lead research organisation Hart Field Site Group
Host research organisation Hart Field Site Group
Trial funding source GRDC UCS00020, UA00149
Related program N/A

The financial assistance of GRDC to undertake this research is gratefully acknowledged (projects UA00149 and UCS00020).

Other trial partners Hooper Consulting and The University of Adelaide
Download the trial report to view additional trial information


Crop type
Treatment type(s)
  • Herbicide
  • Herbicide: Timing
  • Sowing
  • Sowing: Timing
Trial type Experimental
Trial design Blocked, randomised and replicated

Hart 2016

Sow date 20 April 2016
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Download the trial report to view additional method/treatment information

Trial results Table 1

# Treatment 1
Screenings (%) Test weight (kg/hL) Protein (%) Grain yield (t/ha)
1 20th April 2016 0.8 79.2 8.7 3.6
2 2nd June 2016 0.8 81.5 7.1 4.9

Grain yield t/ha


Protein %


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 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.