Recently by Stephen Harrison

So it is now official, last month was the wettest April for 100 years.  Geoffrey Chaucer had it spot on when he said that April with its sweet showers has pierced the drought of March to the root. 

Sprayers have been in and out of the pit lane like a Formula One team and one or two are wondering whether they should switch back from row-crops to proper wet weather flotation tyres.

We are doing our best to make the most of all spraying opportunities by storing the maximum amount of water - in many cases rain water from roofs - and ensuring chemicals are laid out ready.  This means we can maximise the time spent in the field spraying.   Where possible we are using a bowser to ferry water and packs of chemicals to the sprayer to reduce downtime.

A large proportion of the rape has been treated for sclerotinia between the showers.  After starting early, flowering has dragged on slowly and many crops will require a two spray programme. 

It's early spring again, so it's time for the annual discussion with my clients about straw yield and growth regulators. In this area straw is a valuable commodity and farmers like plenty of it. The further west I travel, the more intense the debate becomes. Received wisdom suggests that straw yield is directly related to grain yield.

However, it is a fact that round balers, which many livestock farmers prefer, do not cope well with short brittle straw. In a dry spring the decision becomes even more difficult. I do not see straw values compensating for a severely root lodged wheat crop, so we always stick with the stem base chlormequat and build from there, as the season or field situation dictates.

Wheat is generally at Zadoks GS 30 to 31 which is about normal. There are a few abnormalities in sprinters like Gallant which in low lying, mild or coastal areas is at 32 with the tip of leaf 3 just visible. 

It has also been a busy week for spraying, with a lot of contact graminicides applied to winter wheat in ideal conditions. Cleavers look green and fresh, therefore, a low dose of amidosulfuron has been included where appropriate. The next spraying target will be mayweeds, cleavers and thistles in winter rape with Galera (clopyralid and picloram). The window for this product is very narrow and many crops will need treatment over the next week if it warms up again. 

Oilseed rape has responded well to initial inputs of N (65kg/ha) and SO3 (90 kg/ha). In general, canopies are smaller than pre-Christmas, so cutbacks in Nitrogen will need to be carefully judged. Charlock has been well controlled by frost and specific off-label approval bifenox. Where bifenox was not applied smaller plants have survived.

February again and is spring just around the corner? It certainly seemed like it 10 days ago with fields looking as green and advanced as a normal March. The cold snap has steadied things up and at least the Charlock looks a bit sicker now. Once again frost had the greatest effect where SOLA bifenox was applied previously.

A striking effect of the mild winter was seen last week in South Wales in a BYDV trial. Untreated plots and the guard area around the trial were heavily infected; plants in these areas had roughly half the biomass of those in the treated areas.

Most cereals have high shoot numbers and will require careful nitrogen and PGR management. Even with high levels of mildew winter barley still carries lots of tillers. Wheat is very similar with early drilled Grafton carrying 10 or more tillers. Don't forget that HGCA lodging rating is not an absolute figure and can vary by several points depending on sowing date and shoot number. Root lodging is likely to be most severe in early sown, over thick crops so take every step to keep these crops in check.

Justin Hayward once sang: "my life will be forever autumn" and this is certainly how things feel in the South West at the moment.  Crop growth has carried on unhindered and early November drilled wheats after grass leys are now fully emerged. 

The damp, mild weather has allowed grassweeds to emerge, especially since the last spell of heavy rain wetted through cloddy areas of strong land.  Residual herbicide performance has not been as consistently excellent as last year.

The mild conditions and good levels of blackgrass emergence means conditions are ideal for autumn contact materials and a dry spell this week should see a lot of spraying completed.  Winged aphids are being detected in cereals, therefore, an aphicide will be prudent. 

Insecticidal seed treatments on early-sown crops will be nearing the end of their useful performance so should also be treated.

Drilling has carried on apace in the four weeks since my last entry.  Concern is now mounting over dry seed-beds which are bound to hinder pre-emergence herbicide activity.  Almost incessant wind has made spraying difficult and the strong aroma of certain materials (yellow peril) means extra vigilance is required.

Any dry cloddy patches are slow to emerge although thankfully slug levels have been low - so far! One bonus has been some of the best conditions for years for maize harvesting and subsequent crop establishment.

The other obvious yellow peril is flowering charlock in winter oilseed rape.  We will consider an early dose of bifenox (SOLA) where the crop is well advanced.  Last year best frost kill was seen on pre-treated weeds.

Another autumn and another crop year comes round again. Harvest is largely complete save for a few acres of linseed. Variety performance trials results have been digested and we are starting to chew the fat on some of the fungicide data. 

Variety selection is best made on five years' data rather than one - especially one like the season we have just had. Once again, farm performance of some varieties has exceeded variety trials figures, highlighting the difficulty of applying common management structures across a range of very different plant types. Finding varieties that suit your farm and learning how to grow them consistently well is integral to successful crop production.