The T2 flag leaf fungicide spray is now the focus for winter wheat crops.

Dry conditions over the last month have kept disease pressure low, so much so that product choice and rates are being tweaked accordingly to get the best return from crops.

Our Crop Watch agronomist keep us updated with progress around the country.

See also: Wheat rusts an added threat at Crop Doctor site for T2 spray

North

Patrick Stephenson, AICC (Yorkshire)

What I wouldn’t give for a drop of rain. From the agronomy point of view, the season so far has been relatively easy.

I fear that this is about to change as the dry weather starts to take hold.

The initial panic over yellow rust has turned into an acceptance that there has been some change in yellow rust races. Treatments, when well-timed, have worked well, and the use of tebuconazole far exceeded our initial plans.

Flag leaves have emerged in many crops and what was planned as a T1 followed by a T2 appears to be more like a T1.5 followed by a T2.5.

Except for yellow rust, disease is notable by its absence. The conundrum we face for the choice of T2 fungicide is how do we balance risk and reward?

Historically, 65% of the yield return being from a T2 timing, the risk of not spraying is huge.

On the other hand, spending £65-£85/ha seems far too excessive with the clean crops I am walking.

I completely understand why twin packs are supplied to comply with registration issues, but do we have to have so many?

I am sure Einstein didn’t have to do as many calculations working out the best value combinations.

Time to get out the trusty calculator and work out the path that balances both.

Clean winter barley

Winter barley crops are having their final pass with an ear wash and, following the wheat, are remarkably clean.

Once again, I struggle to justify expensive chemistry on these crops as drought and very little disease challenge me.

A mix of a triazole and strobilurin is my favourite option. Spring barleys are a mixed bag depending on drilling date.

The early drilled crops have established well and have been treated for broad leaf weeds with a fungicide.

The late drilled are currently floundering and have very few weeds in. These fall into the wait-and-see category.

Winter beans are now flowering, and to continue the theme have very little disease.

There will be a chocolate spot spray to apply, but I am resisting the urge to apply now and waiting for the prospect of rain before recommending.

At this moment, my option would be an azole and strobilurin mix. Spring beans have emerged well.

Unfortunately, many of the pre-emergence herbicides have been compromised by the dry weather.

This has meant renewing my love affair with bentazone.

Getting the best out of the product is very akin to sorcery, trying to balance rate, oil inclusion and weather. Sadly, there are virtually no alternatives.

Winter oats are heading towards flag leaf and will be due a second fungicide shortly and, at the risk of sounding like a stuck record, will be based on an azole and strobilurin.

The continuing dry weather (5mm in April) is starting to take its toll on some crops.

The dry weather has meant many crops have remained open, allowing a new flush of broad leaf weeds.

Charlock, fat hen and bindweed lead the charge. I fear we could be in for a trying summer.

West

Antony Wade, Wade Agronomy (Herefordshire/Shropshire)

We have just had the first rain for three weeks with a welcome 5mm, alongside a thunderstorm weather warning.

The dry weather has meant our usual enemy of wheat – septoria – is unusually dormant.

Emerging critical upper leaves are yet unblemished by this robber of photosynthetic area.

However, we have been here before with a dry six-week period in spring only to be followed by four weeks of intermittent rain and septoria levels go from non-existent to no green leaf area.

Our region is always a single rain event from epidemic. We have a plethora of excellent fungicides, but all are best as protectants.

Gone are the days when we talk about “kick-back” of eradicant control.

Although I have quite a few patchy crops, they have filled out quite well, with good light levels for the past month and crop canopy dark green with recent fertiliser uptake.

There is too good a potential to jeopardise by cutting back on T2s.

Rusts have been well controlled by tebuconazole plus azoxystrobin at T0.

The dry weather has meant a lack of expected weed emergence before T1 so I envisage some late decisions on herbicide inclusion at T2 if rain stimulates emergence.

Winter barley T2s have been applied. Wet weather disease levels are low, but ramularia can yet have an impact.

While I have seen benefits of Adipedyn (pydiflumetofen) on this disease, its cost in a crop with low disease and value is difficult to justify.

PGR strategy

At T2, crops were short and stiff following a previous plant growth regulator (PGR) strategy, so I used foliar potassium to help straw strength rather than another PGR.

If we get heavy rain that decision was the correct one.

The enigma that is oilseed rape growing is certainly in effect this season. In general, it is the one crop on farm that has been relatively stress-free.

Most crops have good potential so I applied a robust insurance spray of boscalid + mefentrifluconazole.

Unfortunately, pre-emergence sprays applied to barley have not had enough moisture.

I have been waiting for rain to stimulate weed emergence.

Again, PGR input decisions have been more difficult than usual with crops starting to look drought-stressed and fertiliser still on surface.

So, in general, T1 recommendations were without any PGR.

If we get enough rainfall with luxury growth this is going to complicate T2 decisions and timing.

It is a similar story in maize. We did not have the frosts some had, so crops are looking OK but will welcome rainfall.

We decided not to do a pre-emergence herbicide and rely on post-emergence once moisture is available.

Good agronomy cannot be prescriptive – it has to be dynamic and reactive to changing environmental conditions.

South

Oliver Pilbeam, CCC and CLM (Kent and Sussex)

In East Sussex, we averaged only 35mm of rain in April, but I shouldn’t complain as that’s more than many have had further west and north.

At least dry weather has kept disease levels low. In winter wheats, the cost-effective T1 programme was well timed due to settled weather.

I’m yet to see septoria take off, just yellow rust, which looks to have been addressed early, with leaf four upwards looking clean across most varieties.

It’s the same with brown rust, even in the biggest culprit variety, Crusoe. This, coupled with a dry forecast, allows us to cut back on T2 programmes.

These will be based around varying rates of fenpicoxamid, with the addition of prothioconazole and/or tebuconazole or azoxystrobin. 

I plan to use Miravis Plus (pydiflumetofen) on the stronger-looking, earlier-drilled crops that are carrying more disease but also potential. However, the price is hard to justify on later November-drilled crops.

Protein nitrogen 

We’re turning our attention to protein nitrogen, looking to add 40-60kg N from flag leaf to grain fill. It’s a debate how much to apply, given milling premiums aren’t that exciting.

It’s also easy to forget that some crops simply don’t have the yield potential so would naturally hold a higher grain protein.

With a limited feed market in the South East, missing that 13% milling spec protein mark isn’t an option, so we will err on the side of caution.

I’ll be using Hill Court Farm Research protein prediction tests again to aid this decision.

Spring barley and oats are at GS30 so the T1 fungicide is imminent, with a cheaper prothioconazole-based program due to lack of disease.

These crops look remarkably good considering the lack of rain.  

The pre-emergence chemistry applied to peas and beans went on in dry conditions so hasn’t been hugely effectively on spring-germinating broadleaf weeds.

We are reluctantly relying on bentazone in beans, plus or minus MCPB on peas, to help keep them clean.

It’s a punt due to its varying effectiveness, but we will try high water rates with the addition of oil.

The huge variation in crop potential highlights how the days of simply saying “we’ll do what we always do” are gone.

The nitrogen debate shows the importance of knowing what it costs to grow a crop. 

Markets are largely out of our control, but expenditure isn’t. We have to adapt – and so far this year that means pulling back spending. 

East

Rory Kissock, Farmacy (Essex, Herts, Cambs and Suffolk)

It will be no surprise to report that here in the East conditions remain very dry as it is across the whole country.

I can’t write a farming column and not mention farmers’ favourite topic, the weather, especially rain.

Focus on wheats now surround T2 flag leaf fungicides, with disease pressure being so low that product choice and rates become a fine art to provide sufficient cover for when the weather breaks and getting the best return.

Septoria has a latent period of 360-day degrees. This means crops may look clean but could soon express disease symptoms.

The standout actives, in no particular order, would be: mefentrifluconazole, isoflucypram, fenpicoxamid and pydiflumetofen.

All are good products and will have a position at the T2 timing depending on variety and crop potential.

Weed control has been on the back burner for obvious reasons, however there are small weeds germinating in the base of most crops.

Growers should be aware of herbicide growth stage cut-offs and not get caught out with crops now moving fast.

Spring barley and oat crops have made a slow start but seem to be finding moisture from somewhere and are enjoying the sunshine.

There are various requirements for these crops and it’s tempting to try to tick off as many as possible in one tank. This should be strongly discouraged as the crops are very tender and will be stressed.

Splitting pesticide applications out into a sequence of two, maybe three, sprays will be beneficial.

Beet headache

Sugar beet is certainly causing a headache and growth stage is still varying hugely across the field due to soil type.

Heavy-land beet is growing nicely and has received two broad leaved weed herbicides, which have worked well and have given the opportunity to now target grassweeds.

Light-land beet is slower to go through the growth stages. There have been reports of aphids in the eastern counties, but numbers are still low and not yet at threshold.

Winter beans are getting their first fungicide and nutrition applications.

Benzovindiflupyr gives very good disease protection on beans but is limited to one application per crop, which in the current conditions may be better placed later in the growing season.

A combination of a triazole or a strobilurin plus nutrition may be enough at the moment to keep disease at bay and allow for better chemistry to be used at a later date.

Maize has been drilled into some good seed-beds, which surprisingly have retained moisture well.

Green rows can be seen from a distance and establishment is good, except where the rooks have pulled out the odd few seeds. Weed pressure is low, but I still expect them to appear.

Having recommendations written and chemicals on farm can allow growers to react when the time is right.