Tillage Update 29th April 2021
The promise of some weekend rain is welcome as soil moisture deficits are running close to 40mm in many parts of the country. Winter crops are generally growing well but many later sown spring crops are struggling with the dry cold conditions as Michael Hennessy, Head of Teagasc Crops outlines here
Most winter wheat crops are either approaching leaf 3 emerged or are already have leaf 3 fully emerged, so the first fungicide is now due. Some crops that were sprayed in the last few weeks are showing significant signs of scorch from the frosty and dry weather, this should serve as a reminder to avoid complicated tank mixes in these weather conditions.
The cold dry weather over the past few weeks has reduced disease pressure which will allow reduce spend by using some of the "older" Azole SDHI mixes such as Acsra Expro, Elatus Era or even Adexar (which is in use up this season) at 80% rates. Don't forget to add the multisite Folpet at 1.5 L/ha to help with septoria control and resistance management. In varieties like Bennington, Torp, JB Diego and Graham yellow rust continues to be an issue. Target fungicides with strong rust control like Elatus Era at near full rates.
It’s a difficult time to apply a growth regulator to winter barley during the cold weather as crops are under stress. Many crop are already showing signs of scorch from application in the past few days.
Disease pressure has remained relatively low in winter barley, with the exception of Cassia which as some rhynchosporium appearing in the past few days. Although be careful as some crops leaf scorch from the last plant protection application and this may link similar to rhyncho. If in doubt contact your agronomist. Most crops will not need fungicide till awn emergence timing where ramularia will be the key target. Ramularia is most likely to appear on stressed crops. Early fungicide application is critical to controlling ramularia as these work preventatively. Revysol, Prothioconazole and Folpet all have activity on ramularia but not the level of control achieved by chlorothalonil.
Relatively good emergence has been achieved in spring crops across the country. Crops in lighter soils are starting to struggle due to lack of moisture and trace element deficiencies are evident. Earlier sown crops are at early tillering, weed control and final nitrogen are the priority.
Barley Yellow Dwarf Virus risk is low to moderate for the majority of crops that emerged in the late March/early April window. Below average temperatures, wind and low numbers in winter crops are all factors that reduce risk. Previous Teagasc research has shown that there is no justification for the prophylactic use of insecticides in March sown crops therefore for crops that are now at the important 3-5 leaf stage it is difficult to justify an insecticide application. Aphids may fly into the crop at a later stage and feed but research has shown that while symptoms may show later in the season there is no significant yield reduction.
Crops that emerge from mid April are at higher risk and if an insecticide is justified (aphids in the crop), a Pyrethroid insecticide should be applied at the 3-4 leaf stage.
Louise McNamara, Teagasc OakPark chats about Aphid Control in Cereals and gives some good advice to achieving the correct result in this short video below.
Tillage Edge podcast
Veronica Nyham, a tillage advisor in Laois explained that a number of spring crops are struggling due to pest damage and perhaps sub optimal conditions at planting.
Eoin Lyons, Teagasc/Boortmalt joint program advisor in Wexford, said these poorer crops were mainly confined to the very early planted crops, with a plant stands of 250 plants per meter squared in many crops.
Both Veronica and Eoin also discussed the necessity of completing key agronomic tasks in the coming week despite the cool conditions. The main tasks discussed are plant growth regulators to barley and oats and the main fungicide to winter wheat.
Listen to the podcast here below
For more episodes and information from the Tillage Edge podcast go to: teagasc.ie/thetillageedge
Crop Agronomy webinar
The next in the series of Crop Agronomy webinar is on May 4th at 11.30am
Teagasc researchers, specialists and advisors discuss strategies to controlling weeds, disease and pests on crops from around the country. The webinar will look at cereals, beans, and beet and also look at how to get the best from the plant protection products used on your farm.
IASIS points are available for the webinar. (Zoom login necessary)
The Teagasc Tillage Crop Specialists issue an article on a topic of interest to Tillage farmers every Thursday here on Teagasc Daily