Minimum tillage shown to boost ryegrass content in permanent pasture

The Lloyd family have increased perennial ryegrass in the sward by 30 percent while boosting white clover content
The Lloyd family have increased perennial ryegrass in the sward by 30 percent while boosting white clover content

Using min-till to establish a multi-species sward in permanent pasture has rejuvenated leys at a Montgomeryshire organic dairy farm.

The Lloyd family have been farming organically at Gate Farm, Llandyssil, since 2015, in a system that maximises milk production from grass.

Their herd of 170 Friesian Holsteins produces an annual average yield per cow of 6,600 litres, with 4,100 of those litres coming from forage.

Ploughing has traditionally been used in the farm’s reseeding programme, but they were keen to trial methods that minimise soil disturbance.

Third-generation farmer Glenn Lloyd embarked on a Farming Connect farm project to investigate how min-till, or minimum tillage, could be used to increase sward diversity in permanent pasture.

Since the farm is organic, a herbicide cannot be used before seeding, and the thick thatch at the base of the 30-year-old sward proved a challenge.

Helen Mathieu of Germinal, who provided technical input into the project, said old permanent pastures benefit from a herbicide treatment because old grass weeds and grasses need to be killed off to allow room for new perennial ryegrass.

In a system when this cannot be applied, Ms Mathieu explained that it was important to use the right seed drill for the job.

For the Gate Farm project, a Guttler Greenmaster 300 Tined Seed was used. Mr Lloyd said it had been a “tall order’’, to overseed permanent pasture with a thick thatch.

“It was a big ask, but it was impressive watching the machine work; it really did rip through the thatch," he said.

The field was overseeded with a mixture of plantain, chicory, red and white clover and perennial ryegrass at the end of July, when conditions were very dry.

Performance the following spring was impressive, said Mr Lloyd. “Growth in the spring and late autumn growth has been exceptional," he told farmers attending a recent Farming Connect open day at Gate Farm.

It had an opening cover of 3,100kgDM/ha when it was grazed in late February. Ryegrass content in the field, which previously had a high proportion of meadow grass, had been boosted by at least 30%.

But there had been poor establishment of herbs and legumes – chicory and plantain content was sparse. “The herbs have really struggled with the permanent pasture," said Ms Mathieu.

She advised that overseeding with herbs would be more successful in four or five year old pasture. The condition of the pasture, the type of drill used and the prevailing weather conditions are all important factors for overseeding, she added.

“If it is really dry mid-summer and you get good soil-to-seed contact, it is likely to be more successful; herbs and legumes like to be planted in good time, no later than mid-August."

Although the results from min-till at Gate Farm had been mixed, Mr Lloyd said the project had given him the confidence to include this technique in his cultivation toolkit going forward.

“It has proved that it is possible, but perhaps the soil needs to be aerated too, to get a better result," he said.

Mr Lloyd is also aiming to reduce the farm’s reliance on bought-in feed and, as another Farming Connect project, he grew 11 acres of brassicas using both conventional and min-till establishment.

He opted for Redstart, a hybrid brassica that grows quickly and vigorously, and offers grazing options from July to around the end of January, depending on sowing date.

The crop was grazed with 28 in-calf heifers, each with a daily dry matter intake requirement of 12kg. The crop provided 7kg and round bale silage of 5kg.

Ms Mathieu calculated that the conventional crop grew 3tDM/ha at 15-18% protein and 12ME at a cost 4p/kg, and extended the grazing season by 70 days.

Although the conventionally established crop grew well, performance was poor in the section of the field where the min-till technique had been used to plant the seed into permanent pasture.

“I think this project has shown that conventional cultivation is better for growing brassicas, as they benefit from having a fine, firm and clean seedbed," said Ms Mathieu.