March 15, 2021
Talking Agronomy – Jo Bell – March 2021
Mid-February and it’s clear we’re facing another season in which getting onto the land is our key challenge. The Beast from the East Mk II has brought some welcome cold, but much of our ground is wetter than ever, having had double its 30-year average rainfall for the second month in a row.
Any charlock in our OSR is dying well in the frosts. Where conditions prevented us getting propyzamide on before the end of January, carbetamide has become our weapon of choice. Mindful of not letting the likes of sow thistle get away, we will be monitoring these crops carefully as they come into March for a window to use clopyralid if they are not too far forward.
We are prioritising an early boost from Nutri-Phite PGA (or Quark for very small plants) as well as more nitrogen in the first split – determined from the Agrii N Calculator – for crops with GAIs of 0.8 or less. At the other extreme, those with GAIs above 2.0 may need the extra growth regulation of difenoconazole + paclobutrazol as part of our programme – with rates dependent each variety’s Advisory List lodging risk score. Foliar magnesium and boron will be especially important too after the anaerobic conditions of the very wet winter.
With ground conditions as they are, most of our spring drilling looks like being well into March. The very last thing we want to do is to force crops in. At the same time, Stow Longa research shows we stand to lose around 0.5t/ha from our spring barleys if we don’t leave a good five weeks between spraying off winter covers and drilling.
Thankfully, later drilling really suits the fast-growing Explorer barley we are growing on the £15/t guaranteed minimum premium Budweiser contract. Well-tailored seedbed nutrition – with protected phosphate, in particular – will be vital here for the even establishment so important for the best spring barley performance and fewest harvesting issues. At least half the nitrogen will be going onto the seedbed with the rest to follow soon after.
The persistent wetness also means many of our winter cereals will need extra help to sustain their tillers. So, in addition to careful N timing and rates, thin crops will get an early spray of Quark to kickstart auxin production until they can access their applied nitrogen.
With the right management, the 400 shoots/m2 we are aiming for can still be achieved from plant counts of 90/m2 from October and 140/m2 from November drillings. Alongside this, we will be managing root architecture as well as possible with an early application of the PGR, Adjust that works so well in cool conditions.
The increasing popularity of oats is certainly creating problems in following cereals, with effective early volunteer removal essential. We treated autumn-drilled crops pre-Christmas and expect to have to deal with another weed flush as the weather warms-up.
We are classing any Skyfall drilled from now on as a spring crop from herbicide point of view, with Avadex the base of our programme wherever we expect either wild or volunteer oat issues.
It won’t be long now before our winter wheat thinking turns to disease control. As well as average yield increases of 0.4 t/ha over countless years, a T0 spray gives us the flexibility we need to keep on top of infections even if conditions get in the way of the best T1 timings.
As well the folpet that will be our base for Septoria control – with extra strength on the mildew or rust sides depending on disease development and variety strengths – we are keen to look at some new bio-solutions here. In particular, we plan to try out the elicitor that has given my research colleagues such encouraging results in two years of trialling.
By switching on plant defences to sensitise new as well as existing growth to fungal attack, it looks especially exciting.