The same three varieties that topped the Pasture Profit Index (PPI) in 2019 are top of the list again in 2020, albeit with a slight re-ranking. Aberclyde is back at the top of the list, followed by Abergain and then Abermagic. The Aber range of grass varieties are bred in Aberystwyth in Wales and are sold in Ireland under the Germinal brand. The plant breeders in Aberystwyth have been focusing on quality as a breeding trait for many years and because quality is such an important trait in the PPI, Aber varieties seem to be performing well.

The plant breeders in Aberystwyth have been focusing on quality as a breeding trait for many years

The PPI allocates an economic value to important grass traits. These traits are seasonal growth, quality, persistency and silage yield. The PPI value is expressed in terms of euro per hectare per year over the base varieties. Therefore, the variety Aberclyde, with a PPI of €205, should generate €205/ha more profit each year than the base variety.

This PPI value is derived by combining the economic values of each trait that is being measured. Some traits have more weighting than others, as they are seen to have more economic importance.

Some traits have more weighting than others, as they are seen to have more economic importance

Persistency, quality and spring growth have the highest weighting, while silage, autumn yield and mid-season yield have lower weightings.

The PPI is designed to make selecting a grass variety easier for farmers. By looking at the list in Table 1, you can easily identify the varieties that are strong in each trait. Breaking up the yield figure into spring, summer and autumn and adding a financial value has arguably been one of the greatest strengths of the PPI.

There is one new variety on the list – Nashota, a late tetraploid, comes in with a very high ranking at number four on the PPI. The variety is bred and sold by DLF and is a real all-rounder, scoring high in all traits. Below Nashota is seasoned performer Aberchoice, with a PPI of €176.

There are three tetraploids and two diploids in the top five varieties. Physically, diploids tend to be shorter-growing and denser, with higher ground cover than tetraploids. For this reason, they tend to be preferred by farmers on heavier land. Tetraploids have larger leaves, grow taller and tend to be more open than diploids, so they are not widely used on heavy soils. However, tetraploids tend to have higher growth and quality characteristics.

Tetraploids tend to have higher growth and quality characteristics

Choosing a variety

There is nothing more disheartening than visiting a farmer who has just reseeded a field, only to find out that a middling to poor variety was sown. The investment in reseeding is high, costing over €300 per acre. To get the best return from this, only good varieties should be sown.

Determining whether a variety is good or bad is difficult. As is the nature of things, most grass varieties are good in some traits and weak in others. For me, a good variety is one that is strong in as many traits as possible, but is not weak in any important traits.

As is the nature of things, most grass varieties are good in some traits and weak in others

For example, I could put up with a variety that is poor for silage if it was sown on the milking platform and in a field close to the yard. Chances are, it’ll never be cut for silage.

However, sowing a variety that is weak on quality or early spring growth in the same location is a bad idea. Conversely, sowing a variety that is strong on silage yield, but not as good on early spring growth, might be a good decision on an out-farm that is only ever cut for silage.

Farmers should avoid sowing a variety that is not on a recommended list. The recommended list for Ireland is in Table 1 and similar lists are available for Northern Ireland, England and Wales. Poorer performing varieties will be cheaper to buy, but this is a penny-wise and pound-foolish approach.