Disease levels rise in tandem with temperatures
Published 13/05/2015 | 02:30
Despite the beautiful weather of late April there was little growth due to the very cold and frosty nights. While last week saw lots of rainfall, temperatures remained low and growth has continued to stall.
Winter crops have been under pressure during the cold spell with poor growth but this has helped to keep disease levels low. The improved moisture availability and hopefully improved temperatures this week will change this. This should lead to rapid growth and invariably an increase in disease levels.
The poor weather has made it very difficult to apply the T1 to wheat and barley. Disease levels, particularly Septoria, may start to get a foothold and should receive immediate treatment to remain in control of this disease over the next few weeks.
It is imperative that a very robust rate of a Triazole plus an SDHI is now used, if not already sprayed.
While barley crops have been relatively clean and particularly short to date we can expect this to change suddenly with the main fertiliser application kicking in due to the weather change.
With many crops more backward and shorter than normal a second growth regulator might have been avoided. However, especially for hybrids, if awns have not yet appeared it may be appropriate to apply Cerone at this stage as rapid growth will lead to weak stems and possible lodging problems later on.
Barley should also receive a strong fungicide application of either Bontima, Ceriax, or Siltra. Winter oats has also remained relatively clean and, while still relatively short, may benefit from a late growth regulator such as Moddus plus CCC. Do not apply Moddus past growth stage 32 to oats. A broad spectrum fungicide such as Tocata or Capalo could be used.
Nitrogen top dressing of winter crops is mostly completed with applications of at least 210kgs/ha on winter wheat; 180kgs for winter barley and oats to 145kgs.
Higher rates can be used where yield history allows. Spring barley can be top dressed to 135kgs. plus extra depending on historical yields. It is important to top dress early on malting barley land that tends to yield high proteins.
Trace element treatment
All crops are now in the rapid growth phase and will benefit from trace element treatment. If there is a history of particular deficiencies these should be addressed directly but the application of a general mix can prove very beneficial at this stage.
Fodder beet acreage appears to be back again this year. While this is a specialist crop with specialist machinery required, it would be a pity if the area sown were to drop dramatically as it is an excellent winter feed.
Crops have been slow to emerge due to cold conditions but most are now at the correct stage for their first herbicide. This will mainly consist of a Debut, Venzar and oil mix.
All sprayer operators are probably well aware of the need to register with the Department as a professional user before November 26 this year. Each user needs to have completed a sprayer operator course in advance.
Many merchants and co-ops can organise or recommend courses. Sprayers will require mandatory testing from November 2016 and will require a recognised certificate.
Buffer zones are also now required for all pesticides being applied close to open drains and watercourses. The width of the buffer zone will be related to the product used and for many popular chemicals will be five meters.
This width can be reduced by using the STRIPE initiative (www.agriculture.gov.ie) which effectively means using lower rates and/or low drift nozzles. In many cases this can reduce the buffer zone to one meter.
Finally, there are only 10 days left to get your GLAS application submitted.
This is an attractive option for most tillage farmers with relatively easy undertakings to achieve
Pat Minnock is a Carlow based agricultural consultant and a member of the ACA and the ITCA. www.minnockagri.ie