April 14, 2015
Playing catch-up after a steady start
It’s been very much steady as we go through March into the start of April, with cold nights holding soil temperatures, crop growth and our main yield robbers back nicely. But the Easter warmth has seen everything start to pick-up dramatically. So we’ve got a particularly frantic couple of months of field-walking and working ahead to keep pace with the catching-up our crops have to do.
Only the most forward winter rape is into yellow bud as we enter the second week of April and looks likely to be in full flower in pretty short order. Very noticeable light leaf spot has meant we’ve given all our OSRs a solid preventive spray, in most cases accompanied by a reasonable level of growth regulation.
The exceptions here have been a number of crops badly hit by pigeons. They weren’t a problem at all earlier on. The delayed spring with more than its fair share of false starts, though, meant some big, late flocks that proved impossible to keep at bay.
Thankfully, the same cold conditions have meant pollen beetles have been virtually non-existent so far. Our earlier varieties like DK ExPower and Harper are comfortably through the risk stage now. However, with flowering still a good two weeks away for some other crops, we’re keeping a close eye on beetle numbers. Populations can build to even the new threshold levels very rapidly in a few hot sunny days and the last thing our more backward crops need is any further setback.
Sclerotinia is our main crop protection priority with the rape this month. Although two sprays are technically preferable, wherever possible we’ll be making do with a single treatment this time around. Unless, that is, flowering is seriously prolonged or the rotational threat is especially high.
In these cases, we simply can’t afford to cut corners.
Overall, the steady season so far has been just the ticket for our OSR. The crops haven’t put on too much early growth. Added to good rooting, this means we’ve some strong stands well-set to carry plenty of seed – always supposing nothing serious gets in the way of pod set or fill, that is !
The unexciting early season has been good for our wheats too. They’ve moved ahead steadily and are looking well-tillered, decently nourished and full of potential. Yes, there’s still plenty of Septoria about. But up to now it has been held back by the cold. Thanks in no small measure to the varieties we’re growing, yellow rust has also been kept firmly at bay.
Most of the wheats have Leaf 4 out and, thankfully, more of ours than ever before have had T0s. This will stand them in excellent stead should the weather get in the way of spray timings from here on, as it so often seems to do.
As it stands, Leaf 3 looks likely to emerge from late April. Weather always permitting then, we’ll be applying our T1s by about the time you’re reading this.
Even without a good downpour or two, if the present warm days and dewy mornings continue Septoria could really take-off on any crops that haven’t had a decent T0. This may force T1s to be brought forward, leaving Leaf 3 – not to mention Leaf 2 which will be hard on its heels – without sufficient early protection. In turn, this would seriously compromise the even more critical T2 timing, leaving the flag leaf far too exposed for comfort.
Our aim is to keep the T1 to T2 gap down to three weeks if at all possible – timing our spraying as precisely as we can to leaf emergence. In each case we want to be able to hit as much of our target leaf as possible while leaving it unprotected for the shortest amount of time. This balancing act is especially important with triazoles carrying so much less curative activity than they used to and wherever we have thick canopies from earlier-drilled crops.
Where T0s haven’t been applied there may well be a case for a cheap and cheerful T1.5 to give extra protection to Leaf 2. This is not something I’m considering personally. Instead, we’re using robust T1 and T2 combinations and keeping the flexibility to up the rates if the weather forces us away from our ideal timings.
Steadier growth and the better standing power we’re got in our main varieties means we aren’t planning any PGR treatment beyond T1 either. Every little saving we can make without risking yield will make all the difference this season.
You can email Sam your comments and opinions via firstname.lastname@example.org.