Seven more potential jobs for arable farmers this June and July in the west

Crop Progress

Most flag leaf sprays were applied during May, and ears are emerging to fully emerged, a little bit earlier than most years.

Spring crops are looking good now we’ve had some rain. Most spring barley is in stem extension, while maize growth stages vary from just emerging through to a few true leaves, and some potatoes are well through as we approach the end of May.

Oilseed rape is podding up nicely, while winter barley has finished flowering.

Tom’s agronomy tips for June and July

1. Decide on primary target for ear sprays

Timing for ear sprays in wheat will depend on what you are trying to achieve. If you’re looking for Fusarium and Microdochium control, you should be applying products at early to mid-flowering when first anthers are emerging. Assess Fusarium risk by considering variety, end markets, rainfall – the AHDB has a risk assessment that can help.

Otherwise, if you’re just going for a foliar disease top up, whether Septoria, brown or yellow rust, your timing is a bit more flexible. But bear in mind that, dose depending, your T2 fungicide is likely to only last about 3-4 weeks, so aim for no more than three weeks later for a foliar top up.

Best control of Fusarium and Microdochium will require around 150g/ha of prothioconazole, which is equivalent to 0.55 L/ha of Proline. If there is a risk of rust I would bolster that with the addition of tebuconazole or a strobilurin, but remember both will have only limited effect on Septoria.

There is also the opportunity of using Aviator (bixafen + prothioconazole) if you haven’t used two SDHI-containing fungicides in the programme so far, which might be the case if you’ve used a fenpicoxamid product at T2. For foliar disease top up, 0.75 L/ha, but for Fusarium to get that higher loading of prothioconazole, then rates should be around 1.0 L/ha.

The addition of bixafen will help with Septoria protection, while the Leafshield formulation means it dries within minutes, which is handy in showery conditions. You also get the greening benefits from SDHIs, helping with canopy retention, which often translates into increased yields.

2. Consider second sprays for disease in spring barley

At current barley prices it’s worth protecting crops against aggressive diseases, including Rhynchosporium, net blotch and Ramularia.

Look to apply T2 sprays when awns are emerging, and with resistance issues especially in net blotch, it’s imperative you partner something with prothioconazole to protect the active ingredient. That could be an SDHI, for instance, so applying Siltra (bixafen + prothioconazole) at 0.4 L/ha or Ascra (bixafen + fluopyram + prothioconazole) at 0.7 L/ha, if you’ve not used Ascra already and Ramularia is a concern.

3. Plan early and late blight programmes in potatoes

Plan and consider what sprays you’re going to use for tuber blight control later in the season. There are fewer options available for that, then there is for foliar blight control.

Infinito (propamocarb + fluopicolide) can be used both early in the season during the rapid and stable canopy phases as it is very a systemic product, and later where it superior zoospore activity helps against tuber blight.

My advice would be as you have four applications of 1.6 L/ha to use, to reserve some of those applications for later in the season for its tuber blight control. It’s important to build in some alternation with cyazofamid and amisulbrom products for resistance management.

Early blight (Alternaria is becoming more of a concern, partly because strains are showing reduced sensitivity to strobilurin-based sprays. Use integrated approaches for control – try and keep the crop stress-free, apply appropriate nutrition, and destruction and burial of infected plant debris.

Where it is a concern, for instance with susceptible varieties or where crops are stressed, look to apply Caligula (fluopyram + prothioconazole) as a protectant and to help with resistance management. It sits at the top of the Euroblight ratings table currently. There is a 10-day interval between Caligula applications, and no more than two consecutively.

Caligula doesn’t have activity on late blight, so you will need an appropriate tank mix partner if both diseases threaten.

4. Take care with timing oilseed rape desiccation

Oilseed rape desiccation with glyphosate is good for harvest efficiency, making sure the crop ripens evenly and taking out perennial weeds in the crop.

Don’t go too early as this will limit your yield and oil content. To check timing, find a representative area of the crop, take 20 pods from main racemes of plants, and if two-thirds of the seeds are turning from green to brown in at least 15 of the pods, it’s appropriate to apply glyphosate. Double-check with a moisture meter to make sure seeds are below 30% moisture content.

Do not apply glyphosate to crops intended to be used for seed, and remember there is a 14 day statutory harvest interval, although it might need nearer 21 days.

Check labels for rates, but as a guide for desiccation and annual weed control you’ll need around 1080 g/ha glyphosate, while for perennial weeds and desiccation it will be 1440 g/ha.

5. Weigh up economics versus long term weed control advantages

It’s getting a bit late for spraying off grass weeds in winter crops, as black-grass, Italian ryegrass and bromes if not already, will soon be setting viable seed . Removing plants by rogueing or whole cropping is still good option before seeds start to shed.

Grass weeds are probably not in later flowering stages in spring crops yet, so it’s worth considering the economics of spraying as part of a long term weed control strategy, despite high commodity prices if infestations are high.

If you do want to spray areas off in either winter or spring crops, target the grass weeds during early flowering so glyphosate can be translocated down to the roots. You’ll need to use 1080 g/ha to control flowering grass weeds.

Mapping grass weed patches for future management can easily be done in our digital farming platform, Climate FieldView.

6. Start thinking about oilseed rape varieties

With sky high oilseed rape prices currently there’s likely to be a bit more interest in the crop again this autumn.

Dekalb has a wide range of varieties to suit most situations, including DK Expose which will be a candidate for the AHDB Recommended List this autumn, which has been the highest yielding variety in our European network.

It’s a later maturing variety, which is well suited to drilling in early August, and has good disease, pod shatter and TuYV resistance.

If you’re interested in seeing it, or any other DK varieties in the field, please get in touch or look out for us at Cereals.

7. Weed control in maize

Maize, while competitive later on, needs a helping hand early on in its growth with weed control.

Maister (foramsulfuron + iodosulfuron + isoxadifen) can be used on forage and grain maize, with the addition of the adjuvant Mero, for the control of grassweeds, especially annual meadowgrass.

It’s an ALS-inhibitor so needs to be applied when the crop is not stressed, and the weeds actively growing and onto a drying leaf. The label says apply between GS12-16 of the crop, but try to apply before the 4TL stage because that early weed competition limits yield potential.

It has better following crop options than most other maize herbicides, with any crop can be grown the year following harvest, with only winter cereals in the year of harvest.

Obviously if you have pockets of ALS-resistant weeds on your farm, you may not get full control of these.