June 9, 2023
Cropwatch South – June 2023
After the wet spring, it’s no surprise that many crops have now had a month without rain.
Winter cereals over gravel are already showing clear signs of drought stress; most obviously the later-drillings where rooting was compromised by bad frost-lifting despite our mammoth February rolling efforts.
The dry weather has, however, allowed us to get our wheat T2s spot on – at full flag leaf emergence and within three weeks of our T1s. While Septoria was the main target here, our focus has, unsurprisingly, shifted towards rusts.
Thank heavens we never took our eye of this particular ball because yellow rust has really come through in the past two weeks even though it was notable for its absence at T1. And brown rust is always a threat here.
Crops that didn’t get a decent T0 – not ours, I hasten to add! – are really showing how essential good early rust as well as Septoria control is in our less and less predictable climate.
Bolstering Rylox (mefentrifluconazole + pyraclostrobin) with the most rust-active SDHI, Ceratavo – as we’ve widely done at T2 – should ensure we keep both our brown and yellow rust defences up to the mark for our large Group 1 acreages of Crusoe on the one hand and KWS Zyatt on the other.
Alongside the fusarium that is always our main T3 focus, the next question is what foliar top-up to give our standard prothioconazle/tebuconazole combination? For yellow rust susceptible varieties this is likely to be additional tebuconazole – or a strobilurin where two haven’t already been used. With deficiencies now becoming obvious, we’ll be including some foliar magnesium wherever necessary too.
Then, apart from keep a close watch out for the dreaded blossom midge, it’s just a matter of hoping our wheats are well-enough rooted to withstand what looks set to be at least another two weeks without rain.
We have no such worries with our OSR which continues to be very promising. It only needed a single sclerotinia spray, much of it with Mavrik (tau-fluvalinate) to deal with seed weevils. With flowering as late as it has been, our key priority here is to keep the gate closed as long as possible before desiccation for the best pod fill and oils.
Our February-sown spring barleys are also looking very good as their first awns appear. A robust T1 dealt with high Rhynchosporium pressures well. And another dose of folpet alongside a late PGR at T1.5 should have given us the best Ramularia protection, leaving brown rust as our main T2 target in the coming week.
It’s the later-sown crops – maize and linseed as well as spring barley on heavier ground – we are most worried about. Their seedbeds weren’t as good as we’d have liked and many couldn’t be rolled. So, there’s a lot of soil type-based variation within as well as between fields. We’re doing what we can to relieve obvious drought stress with foliar nutrition, but what they really need is a decent drink.