Watson Seeds: Considerations required for new grass in 2021

However, at Watson Seeds we have really missed the way we normally conduct our business which involves a great deal of farm client interaction.

As a business, we have carried out more than 1000 soil analyses over the last three years and we have recorded an average pH of 5.9 with phosphorus and potassium indexes sitting at 3.1 and 2.3, respectively. These figures, however, gloss over geographical differences – alarmingly, 42% of those sampled were found to be at or below 5.5pH.

Soils are the fundamental building blocks to a productive farm and if new reseeds are to be established and maximum performance achieved on existing leys, fertility management is essential.

The start of the process should always begin with a soil analysis, ideally a year before the field is to be reseeded. It takes a year for conventional lime to neutralise the acidity of the soil and to raise the pH by 0.5 it will take approximately two tonnes of lime.

For example, a soil pH of 5.5, requires two tonnes of lime to take the pH to 6.0 and this will take a year. It should also be noted that higher pH soils tend to have a healthier structure due to flocculation (pulling apart of the clay molecules).

For the establishment of a new reseed, the soil pH should be, for mineral soils, at least 6.3. Failure to address the pH level will severely affect the performance of the new ley. The indices for phosphorous and potassium should be two and above.

It should be noted that new leys have a greater need for phosphate to help with root development and a lower requirement for nitrogen. A well-established sward depends on soil fertility and this will have a major effect on the performance of the sward over its future life.

It is also recommended that soil status should be checked every four to five years to maintain ideal soil fertility.

Grass mixtures have been dominated by perennial ryegrass for around the last fifty years. They can produce considerable palatable forage, but they are reliant on good soil fertility and high rates of inorganic nitrogen.

A multi-species ley as part of the trial

Breeding programmes across the world are heavily focused on the species and they have produced varieties that are high in yield, quality and sugar. They have been and will continue to be a vital component in grass mixtures to provide high quality silage and intensive grazing.

Multi-species leys are increasingly becoming a valuable option in a low input grazing system especially geared towards sheep production. They are made up of diverse grasses, herbs, and legumes.

They offer a range of potential benefits from legumes providing a free nitrogen source with the potential of stretching the grass growing season through the inclusion of varieties such as cocksfoot and timothy. The various rooting depths of the components offer the ability of greater drought resistance and increased trace element uptake.

The improvements in rooting structure and soil health have the potential to improve water infiltration, which leads to a more robust grazing ley during the very wet, as well as the very dry periods. Careful management is key to their longevity and performance.

A perennial ryegrass based high quality silage mixture

They should be rotationally grazed to avoid selective or over grazing and a residual of at least 7cm should be maintained to avoid damage. It is best to give it a long rest period of around 30 days until the herbs are at the correct stage for further grazing.

We have looked closely at the herbal leys through farm trials and by looking at the 1000 grain weights of the various components to formulate our Hermitage and Herbal Ley mixture to perform to Scottish conditions.

They are certainly not a new idea and would be something that Johnny Watson’s grandfather in the 1950s would have been familiar with when mixtures were far more complicated, as can be seen in the mixture below.

With farming coming under ever more environmental scrutiny, a multi-species ley which has the potential to store more carbon, improve soil structure, and to provide a quality grazing platform with less inputs is something that warrants consideration.

A typical commercial mix for 3-8 years ley on medium soil in 1954:

4 lbs Ayrshire perennial ryegrass

14 lbs Irish Grade A perennial ryegrass

4 lbs Irish Grade A Italian ryegrass

2 lbs Danish cocksfoot

3 lbs Certified Aberystwyth S.26 cocksfoot

2 lbs Norton cocksfoot

4 lbs Scandinavian Timothy

¼ lb New Zealand crested dogstail

½ lb Danish rough stalked meadow grass

2 lbs English broad leaved red clover

1½ lb Canadian Altaswede late flowering red clover

½ lb English wild white clover

½ lb Certified New Zealand PP white clover

1¼ lbs English trefoil

½ lb Alsyke clover

The multi-species leys form a vital part of our grass trial work at Upper Nisbet farm, courtesy of Robert and Jaq Neil, where we have sown out 47 plots with a range of varieties and mixtures. Soil health is being monitored with an initial soil health survey and mineral status carried out at establishment.

By looking at the mineral status of the forage samples we are collecting, we will be able to ascertain if the inclusion of deeper rooting herbs is contributing to animal health and performance. Early indications have shown that the multi-species mixtures have been well grazed without material being rejected or trampled.

Traditionally, grasses are tested through frequent cuts throughout the season which fails to consider animal preference and palatability. The first year of this unique trial had been conducted with the aim of getting the animals to perform a key role in what really performs.

Preferential grazing is central to the field evaluation, along with mechanically measuring yield and key nutritional traits. It was evident last year, throughout the droughty spring, what a key role white clover and other legumes played in production and palatability over straight ryegrasses.

Although it is early days in the trial to be in a position to gleam much technical data, we are building up a dataset and the cattle have certainly shown preferences. Some varieties have undoubtedly been leaving lower grazing residuals whilst others have had to be topped to maintain quality.

This information will increasingly be used alongside the appropriate recommended lists to decide on what is included in our Castle Mixtures.

(Insert photo – Giles Henry measuring the plots with Johnny)

It was always expected that Brexit might cause a bit of disruption, but despite some slight delays due to red tape and logistics in Europe, we are in very good shape for supplying the season ahead.

We have secured key varieties with desirable genetics with a lot of them UK sourced, and with even some price easing for our customers to benefit from.