Two Year Study Highlights Recipe for Second Wheat Success

May 2004 - Second wheats can comfortably out-perform many first wheats provided they are managed correctly, according to a special study conducted by ProCam Agronomy with its powerful new 4cast crop management advice tool.

The study, using 4cast's detailed field-by-field performance data from over one million acres of UK crop production each year, reveals Top 25% second wheat crops generating gross margins at least £50/ha ahead of the first wheat average for the past two seasons; a performance achieved through a combination of better yields and lower costs.

"Last year, our Top 25% second wheat crops yielded an average of 8.87 t/ha at a variable cost of £232/ha to earn a gross margin of £767/ha," explained ProCam technical agronomist, Nick Myers. "This compared with a first wheat average of 8.52t at £244 to earn £709/ha.

"In the higher yielding but very much lower priced 2002 season, the overall margin advantage was around £90, underlining the extent to which better-managed second wheats can deliver the goods, regardless of the season.

"Regardless of the season too, our 4cast data also shows second wheats can substantially out-perform their main rotational alternative, winter rape," he added (Table).

Table: ProCam 4Cast Wheat Performance

Crop Yield Variable Cost Gross Margin (t/ha) £/t £/ha (£/ha)* 2003 Top 25% Second Wheat 8.87 26.12 231.55 767.11 Average First Wheat 8.52 28.58 243.49 709.62 Average Winter Oilseed Rape 3.69 61.54 226.99 608.83 2002 Top 25% Second Wheat 9.85 25.06 241.88 648.51 Average First Wheat 9.04 27.51 248.65 558.09 Average Winter Oilseed Rape 3.77 58.51 220.38 548.31

^*At standardised crop prices to eliminate individual marketing and sale timing distortions;
2003: Group 1 wheat £90/t; Group 2 wheat £85/t; Group 3/4 wheat £82/t; OSR £160/t
2002: Group 1 wheat £72/t; Group 2 wheat £68/t; Group 3/4 wheat £60/t; OSR £145/t

So what exactly is behind the superior performance of ProCam's Top 25% second wheat growers ? Having ruled out a simple climatic advantage from the fact that the crops were as well spread out across the country as their first wheats in both years, Nick Myers' analysis of the data highlights three critical agronomic success factor - establishment method, variety selection and take-all management.

"Interestingly, the overwhelming majority of the better-performing second wheats come from ploughed rather than min-tilled ground," he explained. "And when we look at all our second wheat performance data over a four year period we find a clear 0.5 t/ha yield advantage for crops established on ploughed ground - 8 t/ha compared to 7.5t/ha on average under minimum tillage.

"This is quite different from the first wheat figures which show no yield difference at all between the two regimes. Maybe ploughing is giving a particular advantage to second wheats through better trash burial, soil structure and weed control."

In variety terms too, the ProCam data shows some interesting trends. The balance of wheat varieties being grown last year, both in second cereal slot overall and amongst the Top 25% performers, was very similar to the national position - around 35% Group 1 and 2s; 45% Group 3s and 20% Group 4s.

There were marked differences from national planting statistics at individual variety level; especially so in the Top 25%, where only 11 different varieties featured. Most notably, at 42% of the top-performing second crops, Consort was by far the most widely grown variety, with Claire taking just 5%. Next most popular variety was Hereward (18%), followed by Napier (11%), Soissons (8%) and Savannah (6%). Option, Tanker, Charger, Malacca and Xi19 were the only other varieties included in the Top 25%, all at 2-3% of the crops.

"It came as no surprise to see how few varieties made-up the Top 25% and which ones stood out amongst them," Nick Myers observed. "With the possible exception of Soissons, the most popular choices were all varieties we know from experience perform well as second wheats. And we also recognise the value that many of our growers get from the early harvestability of Soissons, giving them a particularly good rape entry.

"The best second wheat growers are clearly selecting varieties wisely on the basis of their established suitability and reliability for the rotational slot. Although all the top crops were sown by October 10, they also appear to be prioritising take-all control in their management."

In particular, Nick Myers points to the relatively large proportion of the Top 25% performing crops in 2003 (58%) receiving a take-all seed treatment. Amongst these, his analysis further reveals those treated with the specialist dressing Latitude producing a yield of 9.50 t/ha - a benefit of 0.6t/ha above the group average

"So we are seeing a clear recipe for second wheat success emerging," he concluded. "Plough the ground, plant the right variety and make sure you use a specialist seed dressing if you're sowing before mid-October.

"Combine this with more and earlier nitrogen plus good eyespot control for early sown varieties without the superior resistance of Consort while avoiding the lightest land and I can see no reason why you shouldn't be able to get your second wheats performing as well as many of the country's first crops."

"So, all-in-all, wheat/wheat/rape rotations look like being one of the best combinable cropping options for our unsubsidised arable future. I'm certain we'll be seeing more of them in the years ahead."