4Cast Recipe for Second Wheat Success
Nick Myers, Technical Agronomist

March, 2005 - Second wheats can comfortably out-perform many first wheats provided they are managed correctly, reveals a special two-year 4Cast study.

Using detailed field-by-field performance data, our study shows Top 25% performing second wheat crops generating gross margins at least £50/ha ahead of the first wheat average for the past two seasons; achieved through a combination of better yields and lower costs.

Performance Records
In 2003 the Top 25% second wheat crops on the 4Cast database yielded an average of 8.87 t/ha at a variable cost of £232/ha to earn a gross margin of £767/ha. 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, the 4Cast data also show second wheats can substantially out-perform their main rotational alternative, winter rape (Table).

Table: 4Cast Wheat Performance

Crop Yield (t/ha) Variable Cost £/t Variable Cost £/ha Gross Margin (£/ha)* 2003         Top 25% Second Wheat 8.87 26.12 231.55 767.11 Average First Winter 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 Winter Wheat 9.04 27.51 248.65 558.09 Average Winter Oilseed Rape 3.37 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 Top 25% ProCam 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 other wheats in both years, our detailed analysis of the data highlights three critical agronomic success factor – establishment method, variety selection and take-all management.

Establishment Method
Interestingly, the overwhelming majority of better-performing second wheats came from ploughed rather than min-tilled ground. Indeed, performance records over a four year period reveal a clear 0.5 t/ha average 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 first wheat figures which show no yield difference at all between the two regimes, suggesting that ploughing could be giving a particular advantage to second wheats through better trash burial, soil structure and weed control.

Variety Selection
In variety terms too, the 4Cast data highlight some interesting trends. The balance of wheat varieties grown in 2003, 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, however, 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 comes as no surprise to us to see how few varieties made-up the Top 25% and which ones stood out amongst them. With the possible exception of Soissons, the most popular choices were all known through experience to perform well as second wheats. And this variety offers well-established advantages in early harvestability as a particularly good rape entry.

The 4Cast results show the best second wheat growers clearly selecting varieties on the basis of their established suitability and reliability for the rotational slot.

Take-All Management
Although all the top-performing 2003 crops were sown by October 10, the best growers also appear to be prioritising take-all control in their management, a relatively large proportion of the crops (58%) received a take-all seed treatment. Amongst these, analysis further reveals those treated with the specialist dressing Latitude producing a yield of 9.50 t/ha – fully 0.6t/ha above the group average

Recipe for Success
These data point to a clear recipe for second wheat success.

Plough the ground, plant the right variety and use a specialist seed dressing if 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 there is no reason why your second wheats shouldn’t perform as well as many of the country’s first crops.