Crop Watch: Signs of spring see field workload pick up

Spring fieldwork is being fitted in between the rain showers as our agronomists give advice for delayed spring drilling, weed control options and perhaps even missing out an early T0 fungicide spray.

Where spring barley is being drilled late, seed rates will have to be increased, and also nitrogen and herbicide applications adjusted to take into account the likely lower yield potential.

See also: Video: Sugar beet drilling starts as growers play catch-up

Once warmer weather appears, crops will race through their growth stage, so agronomists are urging growers to try and keep on top of fieldwork in the very busy next few weeks.

East: Marion Self

Prime Agriculture (Suffolk)

marion self

Marion Self

A sigh of relief as the mid-April forecast promises drier, more settled weather. As field conditions dry, wheels are turning and the heavy spring workload is underway. Expect fast growth as crops respond to warmer temperatures, recent nutrition and increasing day length.

Spring drilling has been delayed but hopefully much should be achieved in the next two weeks. In sugar beet, remember to start the post-emergence herbicide programme with combinations that are safe to the crop. 

This is important in drier/warmer conditions where beet emergence is uneven and “difficult” weeds like knot grass are already growing. It’s important not to let these weeds get away.

For later-drilled spring barley there will be a lower yield expectation, so final nitrogen dose and herbicide programmes may need adjustment.

See also: Two varieties lead spring barley drilling season

T0 fungicides on winter wheats are underway and for most crops well-timed sprays (beginning of stem extension) offer disease protection, until a well-timed T1 application (emergence of leaf 3) later this month.

Despite lower early disease pressure, septoria and rust development will increase as temperatures rise. For the control of these diseases and for resistance management it is important to keep sprays robust, with tight timings between the applications.

Oilseed rape is extending, with forward crops now at yellow bud. If a planned plant growth regulator has been delayed due to heavy workloads there is still scope to apply these treatments.

As crops near yellow bud the benefits of treatment will shift from a reduction in crop height and lodging to those associated with canopy manipulation such as improved light penetration.

South: Richard Harding

Procam (Sussex)

Richard Harding

Richard Harding

It was beginning to feel rather surreal driving past fields at the end of March without a sprayer or tractor in sight.

Nevertheless, the weather is allowing progress to be made on the backlog of fieldwork and frustration, which has now built up in equal measure. On the lighter soils of the Downs good progress has been made with spring drilling.

Spring barley has gone into very good seedbeds and good soil moisture has allowed pre-emergence herbicides to work well. Where heavier soils are yet to dry, patience will be needed to drill into the right conditions to offset the potential yield penalty of later drilling dates.

The priority is getting the stem extension fungicides on oilseed rape crops, which are putting on rapid growth. While pollen beetle can easily be found in crops, recent AHDB work suggests pollen beetle numbers are rarely damaging.

T0 fungicides, plus plant growth regulators, have, or are about to be applied, on both winter wheat and winter barley. There is a huge variation in growth stages, depending very much on whether ground conditions have allowed early nitrogen to be applied.

Despite later T0s on winter cereals this spring, plans are in place for T1 timings, which are likely to be in the latter part of April, with the aim of targeting the emergence of leaf three. This is the critical timing for the suppression of what is likely to be a high-septoria-pressure season.

While the frost, snow, and generally colder weather has had a positive effect on yellow rust levels, it has only slowed rather than eradicated it from crops.

Varieties with low disease scores and high yield potential sites will see T1s based around the actives epoxiconazole, azoxystrobin, chlorothalonil, and the SDHI  benzovindiflupyr. This is a robust mix, particularly useful where a T0 has not been applied.

North: Mary Munro

AICC/Strutt & Parker (Perthshire) 

Mary Munro

Mary Munro

The prolonged wintry weather is a massive headache for arable farmers, but our hearts go out to the livestock producers struggling with awful conditions for lambing and calving. A further dollop of snow at Easter really set everyone back on their heels again.

A year ago this week we were in full swing with spring sowing, spraying and fertiliser spreading. So far, most, but by no means all, the winter crops have had one dressing of fertiliser, and a few growers on lighter ground have sown some beans.

The winter crops are quietly moving on though, and in terms of growth stages are probably only a week or two behind the norm. Where they have had a boost of nitrogen they are looking well, and disease levels are minimal.

Lower leaves have dropped off, so plants are generally clean. It is a good time to evaluate the differences between varieties and plan for the risks ahead.

The oilseed rape crops barely moved in March but are just starting to extend, and the crop protection plan is unchanged – a fungicide for light leaf spot to go on when ground conditions allow.

Normally T0s would have been on wheats by now and a 3-4 week gap expected before T1. For many crops this is not going to work, and once temperatures rise the crops will shift through the growth stages quickly.

I do not see much point applying a T0 knowing that the T1 will be due a fortnight later, unless there is disease to knock out, so my inclination is to skip T0 and go for T1 at the early end of the spectrum, with all of the plant growth regulator dose.

The challenge is to time the sprays as close to the right growth stage as possible, especially with T1 and T2. The winter barley plan is unchanged: two shots of Siltra XPro, the first without chlorothalonil, the T2 with chlorothalonil to counter ramularia.

West:  Antony Wade

Hillhampton Technical Services (Hereford/Shropshire)

antony wade

Antony Wade

Looking back at my article last month, I really wish I could say we have cracked on with the backlog of fieldwork, but opportunities have been very limited, with ground conditions challenging.

The occasional dry day has been snatched to get some of the oilseed rape sprayed, but in some cases the herbicide had to be withdrawn as the buds were too far emerged.

I will still be looking to get some plant growth regulator applied at green to yellow bud either as a specific growth regulator, such as Caryx, or an azole with growth regulator activity, such as metconazole or tebuconazole.

Wheat and barley have only had their first nitrogen-sulphur first splits, so certainly barley and second and late-planted wheats will be a priority once we can travel, two dry days at the end of last week allowed some to make a start.

A few T0 recommendations for September-sown wheat were sent out pre-Easter, but 64mm of rain over that weekend have meant that these are still in the store.

I am hoping that this week offers some drier conditions so that we can get some chlorothalonil on to hold the significant septoria that is present on lower leaves. If we don’t we may be looking at going straight to a robust T1, which will probably include an SDHI.

The winter barley T0 boat has well and truly sailed so I am now planning an earlier GS31 T1 timing with disease levels low I am not concerned about this approach. But, like the oilseed rape, I am expecting a growth spurt and without any early plant growth regulator applied this is more of a concern than disease control.

Very little spring drilling has been done and, as others have commented, this will probably have an impact on the yield potential of all spring cereals and pulses. We will stick with them until the end of April, but after that it may be better to leave the seed in the shed.