Autumn drilling
With drilling of winter cereals having already started there have been many questions posed about the required seed rates for the different crops and varieties. Shay Phelan, Teagasc Crops and Potato specialist, discusses autumn drilling.
As always the rates used last season may not be exactly correct for the current season as the thousand grain weight (TGW) for 2022 crops will have been different than those harvested in 2021, therefore the seed rates may well have to be adjusted to reflect this.
With ground conditions being very good at the moment there is some scope to reduce seed rates earlier in the season and then increase the rates as you progress through October. As soil conditions normally deteriorate the later you drill, seed rates need to be increased to compensate for potentially lower establishment rates. Base the seed rate on the current TGW which should be printed on the bag, for home saved seed then simply count out 1000 grain and weigh them this will give you the TGW for your seed. Remember TGW may change between batches of seed and varieties so carry out regular checks.
Table 1. Indicative winter barley seed rates for early autumn drilling 2022
| Sowing date (week) | Sept – 4th Week | Oct – 1st Week | |
| Target plants m² | 270 | 280 | |
| Sowing seeds m² | 318 | 350 | |
| % Establishment | 85% | 80% | |
| TGW1 | Kg/ha | ||
| KWS Cassia | 53.5 | 170 | 187 |
| LG Casting | 52 | 165 | 182 |
| KWS Infinity | 53.1 | 169 | 186 |
| Bordeaux | 54 | 172 | 189 |
| KWS Joyau | 48.9 | 155 | 171 |
| KWS Tardis | 55.9 | 178 | 196 |
| Sy Armadillo | 47.7 | 152 | 167 |
| Belfry* | 46.6 | 93 | 93 |
| Bazooka* | 47.6 | 95 | 95 |
Notes; * 6 row hybrids are drilled at 200 seeds/m2
1 TGW quoted on the table are from the 2023 DAFM recommended list which are the 3 year average may be different than what is available.
Weed control in winter cereals
Many growers have now moved to pre-emergence weed control for autumn drilled cereals as this tends to give better control of grass weeds. Products such as Firebird, Defy, Flight, Stomp Aqua, Tower etc. are very effective when used pre-emergence of the crop or weed. However good knowledge of the predominant weeds in the field is required to ensure that the correct herbicide or mix of herbicides are selected to control those weeds. Contact your local Teagasc advisor for details of the weeds controlled by different herbicides.
Jimmy Staples describes the results from the 2020 weed screen trial in Oak Park which compares the performance of different herbicides used both pre and post emergence to control a variety of weeds.
Spraying pre-emergence herbicide
Tillage edge podcast
On this week’s episode of the Tillage Edge podcast, you’ll hear from moderator Andy Doyle discussing the issue of fertiliser supply and costs with Kieran McEvoy from the IFA, Clive Carter from IGG, as well as Donal Maloney from Tirlán, Enda McDonald from Grassland Agro, Bill Callanan from the Department of Agriculture, Food and the Marine, and Teagasc’s tillage specialist, Ciarán Collins.
For more episodes and information from the Tillage Edge podcast go to:
https://www.teagasc.ie/crops/crops/the-tillage-edge-podcast/
Find out more information and advice from the Teagasc Crops team here. Find your local Teagasc office here