Peter Griffith

7 September

Trying to make sense of the latest HGCA wheat trials.

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I’m now looking for uniformity in the remaining data to determine if there is a significant difference in varietal performance to make an informed decision on what to grow this year either as a first or second wheat. Fat chance as only Suffolk and Cambridgeshire are represented by both and I’ve already dismissed the results from the second wheat site in Cambridgeshire due to the very low yields. I’m left then with only a comparison between two sites in Suffolk which reveal an average drop in yield of around 1.5 t/ha for growing a second wheat, which is pretty much what I would expect. I’m also consoled by the fact that Oakley is coming in as the top yielder in this second wheat slot which reflects what I’m finding in the field.

Turning my attention to first wheats reveals the dangers of only using one year’s data especially in a year like this. The two sites in North Yorkshire, both first wheat and sown within a week of each other have a difference of 4t/ha in mean yield. In fact across all first wheat sites the average yield difference for all varieties is over 6t/ha. Dropping the low yielding site in North Yorkshire from the equation only reduces this difference to 5t/ha. This variation in yield makes for a meaningful comparison of variety performance nebulous at best and downright dangerous at worst. In fact by dropping the worst site and recalculating the average yield per variety I’m left with Oakley performing as well as any other variety as first wheat. So based on this analyses I’m faced with a very easy choice it’s Oakley for all wheat fields this autumn. Better lay in some extra fungicides too just in case yellow rust decides to land on my fields.

However, common sense will prevail and so for this year I’m relying heavily on the 4 year mean as a way of determining variety performance and treating this year’s figures as an interesting insight into the influence of climate change on wheat yields in UK. But I’ll still grow some Oakley.

Click here to see the HGCA trial results.