With no real rain in the forecast, concerns are growing with some crops already showing signs of stress due to the lack of moisture. Spring crops also will soon need a drink to fulfil their full potential, and help with herbicide.

Ears are now emerging on some advanced crops of winter barley and the T2 fungicide timings are approaching for some early crops of wheat.

South

Richard Harding

ProCam (Sussex)

With only an average of 3-4mm rain this week, the Downs remain very dry, and the weather looks set to stay that way, which is now beginning to cause concern as some crops are starting to show signs of lack of nutrient uptake despite fertiliser applications. However, most crops are growing well.

Winter wheat crops have all received their T1 fungicides, apart from a few late-sown crops.

The majority of crops have leaf 2 emerging and a few early-drilled crops of Extase and Crusoe are at GS37 with the flag leaf just visible.

Septoria remains at low levels, but can be found on older leaves high in the canopy and likely to be rubbing against higher new leaves. So it will be important to ensure T2 applications are well timed.

Yellow rust can be found easily, with weeds such as grounsel also covered in rust in the bottom of cereal crops. However, tebuconazole remains a cost-effective fungicide to stop this disease.

Final main fertiliser applications are being made regardless of the weather, which will just leave late applications to milling wheats.

Winter barley crops are rapidly moving through the growth stages. The most advanced crops now have awns appearing, if not fully emerged in a few cases.

The less advanced crops are now at the growth stage for a final growth regulator to prevent brackling, which this year will be Terpal (ethephon + mepiquat ) at 0.5-0.75 litres/ha depending on the level of risk for each crop.

T1 fungicides were applied two to three weeks ago, and with the current low disease risk there is no rush for T2 fungicides until the awns are fully emerged. This is likely to be in only another seven days.

Oat crops

Winter oats are showing signs of running out of nitrogen, with applications having been made after the recent showers. The remaining crops will be completed in early May.

Broad-leaved weed control has now largely been carried out where necessary, while growth regulators have been delayed where crops are showing signs of stress.

There is no sign of crown rust yet and a protectant fungicide of tebuconazole or a strobilurin will be combined with the growth regulator.

Spring cereal fertiliser applications have all been completed, except spring wheat, which might still have a later dressing depending on its potential.

Both wild oat sprays and broad-leaved weed control remain a moveable feast as weed emergence remains erratic and certainly nowhere near complete.

Oilseed crops have high numbers of seed weevil in some crops. Overall flowering is progressing well, and pod set looks good.

Second flowering fungicides will be due two weeks since the last application if flowering is continuing.

West

Antony Wade

Hillhampton Technical Services (Herefordshire/Shropshire)

April 2022 bares quite a resemblance to 2021, mainly in terms of being pretty dry, although this season has not been as cold as 2021, where we had record number of frosts. And while it hasn’t been a “hot” spring, we have had some warm periods.

So as a result, crops have responded probably slightly earlier than benchmark dates would tell us.

However, some of the forward growth in some of the wheat crops is more due to the lack of a significant spell of winter weather than the early spring weather.

This is especially true in the case of varieties with spring-type parents such as Extase.

Therefore, the variety is becoming pretty unpopular with me for its unsettling earliness and that drilled anytime before mid-October in this region it is carrying as much septoria as varieties with lower ratings.

In my opinion, T1s went on well timed, although generally some of leaf 2 was emerging, this was no bad situation in dry conditions to ensure all leaf 3 were fully out and some coverage of leaf 2.

This will mean that the gap to T2 will be no longer than three weeks and again we will be able to be patient to ensure most flag leaves will be fully emerged.

We have been lucky in receiving some rainfall in recent days – only amounting to about 10mm, so enough to help fertiliser utilisation, but along with some heavy dews, enough for septoria to spread.

Yellow rust in our area is still difficult to find. At a recent farm walk of trials with Adas, I was promised yellow rust on susceptible varieties, but there was only significant levels in the untreated plots.

Barley awns

Winter barley shows promise as they always do in May, when the sea of ears start to emerge and crops look “easy on the eyes”.

Similar to last season, crops were not looking too much of a lodging risk ahead of T2 so only occasional crops had to have further PGR. But where they didn’t, foliar potash was applied to assist straw strength.

This strategy seemed to be successful last season, but the sea of promise could be dashed on the rocks of the weather gods if dull, wet and windy hits grain filling.

Oilseed rape crops are still flowering quite strongly, with many of my most forward crop starting to flower three weeks after a fungicide application.

With a warmer, damper forecast for the coming week, these are likely to get another fungicide to protect against sclerotinia in a now very valuable crop, especially if it fulfils its yield potential.

Spring crops desperately needed a drink. While I don’t have any light land that is parched and wilting like some, even in our region they have only had enough to “wet the whistle” and will need further rain to make decent potential crops.

There has been some weed germination, but the tricky decision is how long you wait before deploying the contact herbicide in crops that will race through the growth stages, challenging spray timings.

Maize is another crop that will need some rain to help it emerge and get away, and also to help the activity of any pre-emergence herbicide that has been applied.

East

Marion Self

Prime Agriculture (Suffolk)

Light rains have provided some stress relief for crops, growers and agronomists.

These showers have enabled crops to take up nitrogen and function better, but as temperatures warm, more water is needed, especially on lighter soils where dry conditions are biting crops hard.

Wheat crops are at or approaching flag leaf emergence and the T2 fungicide mix is due soon.

Despite dry conditions in early spring there are clear differences in the level of septoria on the bottom leaves between varieties, reflecting their inherent disease resistance.

Flag leaf sprays should be well timed and doses adjusted according to variety to keep the upper leaves of the canopy clean.

Yellow rust pressure is high, and although infection has been held by previous treatments, it is important that sprays are kept robust and tight (about three weeks apart).

Many growers will be using newer chemistry based on “Revysol” or “Inatreq” at the flag leaf timing.

These actives offer the strongest septoria control, but where rust risk is high, they may need some support from tebuconazole or strobilurins to maintain rust control. 

At this timing, growers should also consider whether to apply a late-season PGR, depending on previous inputs, crop strength and growing conditions.

Long flowering

Oilseed rape has benefited from the dry, cool weather; as a consequence, the long flowering period should enable crops to maximise their seed potential.

If the weather becomes more unsettled, with light rain and increased humidity, the risk of sclerotina will increase.

Depending on weather conditions, a second spray towards the end of flowering should be considered. The AHDB Sclerotina Risk Model can help with this decision.

At current selling prices, a small yield response will give a large return on investment.

Pulses are enjoying the season, most noticeably winter beans, which look well and are full of flowers. Their fungicide and nutrition programme has started and will be managed according to disease pressure.

Spring cereals have now established well, recent showers have encouraged a flush of weeds and they are ready to receive a mix of fungicide, herbicide, micronutrients and PGR as appropriate.

Despite a tricky start, sugar beet has also relished the recent showers, and crops have largely now reached a size to enable robust herbicide applications.

Aphid pressure is increasing and insecticide should be applied to non-Cruiser-treated crops at threshold (one green wingless aphid for every four plants up to the 12-leaf stage). 

Growers will need to monitor untreated crops carefully, small aphids can be hard to distinguish from grains of soil so take a hand lens.

British Beet Research Organisation (BBRO) Advisory Bulletin #6 is an excellent guide to aphid identification. And check the monitoring site results on the BBRO website.

North

Mary Munro

AICC/Strutt and Parker (Perthshire)

Like everywhere else, the east of Scotland has been extremely dry recently, and showers have been very isolated.

However, there was more moisture in the ground than last year for drilling the spring-sown crops and they are looking good.

Weed control and manganese are being applied about now, on crops ranging from leaf 2 to two tillers.

Winter barleys have all just had the T2 and plant growth regulator, which in most cases will be the final fungicide, but I will be keeping my eye on them because of the pressure from rhynchosporium, which is high this year.

Crops are clean at the moment. I will be interested to see how the various fungicide options compare in terms of ramularia control later in the season.

Oilseed rape crops are in full flower and the decision to omit sprays for light leaf spot has been justified as they are spotless.

I am not going completely fungicide-free with them and all are getting, or have just had, a mid-flower spray of Aviator (bixafen + prothioconazole).

We are not facing any great challenge from weevils and I have never seen them in numbers that would merit insecticide.

Stressed wheats

Some of the wheats are struggling for moisture, and showing signs of stress. Leaf tissue analysis is coming back with a range of deficiencies, which suggests that uptake is the real problem.

Nitrogen prills have been very slow to disappear, and it is clear that rain would cure many of these ills. However, a lot of crops are still looking great, and the yield potential is promising.

My Lothians winter wheat crops are all around GS 31-32 so may or may not quite have had T1.

This year I have plumped for Ascra XPro (bixafen + fluopyram + prothioconazole) for T1 and the T2 will be Revystar (fluxapyroxad + mefentrifluconazole) or Univoq (fenpicoxamid + prothioconazole).

Even in dry conditions, septoria is never far away in Scotland and my fear is that the next rain will be a mighty dollop, ideal for spreading this disease.

The Perthshire wheats are just coming up for T1 and very clean. Yellow rust has not really been a threat for us this season – but thankfully I am not dealing with the most susceptible varieties.