Tillage Update - 10th February 2022
In this week's Tillage Update Shay Phelan, Teagasc Crops Specialist has fertiliser advice for 2022 plus the latest on winter oilseed rape, Green Area Index (GAI) and using the GAI app, winter crop walks information and details of the recent Malting Barley webinar, all here on Teagasc Daily.
Fertiliser Advice for 2022
With the increase cost of fertilisers, particularly nitrogen, putting significant pressure on crop margins for 2022 much debate over the last few months has been around how much should be applied to crops for the coming year. Richie Hackett addressed this issue with his paper at the recent Teagasc Virtual Tillage Conference 2022 where he looked at the relationship between the cost of nitrogen and the value of grain. Based on the most recent costs he calculated that for winter wheat and barley crops that the optimum rate of nitrogen should be reduced by between 25 and 30 kg/ha from the maximum recommended rate. This is based on the Breakeven Ratio (BER) i.e. the ratio between the price of grain and the price of nitrogen changing from a 6:1 ratio in 2021 to 11.4:1 in 2022. He also noted that this decrease in nitrogen rate may reduce yield by up to 0.2 T/ha but that this will depend on a variety of factors.
Figure 1. Nitrogen response curve 2022 vs 2021 based on BER
In the case of P and K fertilisers then the advice is where soils are index 3 or less then match applications to the average off-takes over the last three years. It will be prohibitively expensive to build fertility at soil indices 1 or 2 this season but you should still meet the crop requirements. Where soils are index 4 then there are opportunities to take P or K “holidays” for this season, however beware of high pH soils where there is an allowance in index 4 for 20 kg/ha of P due to a lockup issue.
Winter Oilseed Rape
The Green Area Index (GAI) of crops vary widely this year with pigeon grazing continuing in many crops. To get an accurate measurement of the Green Area index of the crop you can simply use the GAI app on your IPhone. This is very important this year as it will directly influence the amount of chemical nitrogen required. Teagasc have recently published a video showing how to use the GAI app to calculate the green area index and this is available on the Teagasc Crops YouTube channel (watch below).
Calculating the Green area Index is an important tool in calculating the nitrogen requirement of oilseed rape.
A nitrogen calculator is available on the Teagasc Website at Oilseed Rape - fertilisers
P & K recommendations for winter oilseed rape
Fertiliser: Apply a compound fertiliser that matches the N, P & K requirements of the crop at the first application. Allow for 25-30 Kg/ha of Sulphur for winter oilseed rape crops in the fertilizer, this should be applied in the first and second splits.
Winter Crop Walks
A series of winter crop walks concentrating on the agronomy of winter cereals and oilseed rape will commence on Tuesday February 15. For further details visit the events page on the Teagasc website. Also see Teagasc Regional Winter Crop Walks - February 2022
Malting Barley Webinar
At the recent Malting Barley webinar, topics such as nitrogen advice for distilling barley, the contribution of cover crops, Boortmalt/Teagasc joint programme and the carbon balance of crops were discussed.
View the Malting Barley webinar below:
Find out more information and advice from the Teagasc Crops team here. The Teagasc Crops Specialists issue an article on a topic of interest to tillage farmers every Thursday on Teagasc Daily. Find your local Teagasc office here