RED CLOVER has had a bad reputation with sheep farmers ever since Australian research – conducted over 50 years ago – linked it to fertility problems in ewes.

This is unfortunate, given that the nitrogen-fixing legume needs no fertiliser, is a rich source of homegrown protein, and offers increased resilience against drought – all attributes well-suited to the coming era of environmentally-friendly farming.

So a fresh effort is being made to uncover the truth of those old fertility fears, with a group of farmers grazing their flocks on leys containing a percentage of red clover as part of a trial which, it is hoped, will encourage other farmers to make use of the many environmental and business benefits of the plant.

Gillian Preece, a sheep farmer and senior consultant at ADAS, who is coordinating the field lab trial, explained: “We know there are UK sheep producers using red clover successfully in their grass leys, but the science hasn’t caught up with them, and the research that exists has relevance issues.

“Red clover contains phyto-oestrogens, which when fed in large quantities can trick the ewe’s body into thinking she’s pregnant, thereby stopping her from cycling. In previous studies, ewes were grazed on leys containing 100% red clover, so they would have got a big hit of oestrogen.

“But most farmers in the UK would hardly ever do this and would be much more likely to include red clover in smaller quantities as part of a mixed herbal ley,” said Mrs Preece.

In fact, the four farmers in the field lab, who are based in the West Midlands and Powys, will be grazing a selected group of their ewes on herbal leys containing around 10% red clover, before and after tupping, to test the impact on pregnancy rates.

One of the farmers taking part in the trial is Tim Teague, a Romney sheep producer who farms around 500 acres of mainly grass in Shropshire, lambing 1800 to 2000 ewes next Spring.

“I’d read lots of conflicting advice about grazing breeding ewes on red clover,” said Mr Teague. “I asked everyone I could about it and everyone who was experienced in using it said they hadn’t had any problems with fertility.”

Last year, before the field lab began, Mr Teague tried his breeding ewes on a ley containing about 25% red clover, with successful results. “The ewes took the tup really well – we had a very high scanning percentage at 188%,” he reported.

He now hopes the trial will confirm what he has already found and give other farmers the confidence to use red clover: “Red clover really opens up a lot of opportunities. It provides a really high-quality feed, and so we now finish as many lambs as possible on it and tup on it too. It also helps deal with drought. Thanks to red clover, we now don’t buy in any nitrogen fertiliser or feed other than a bit of fodder beet, and my business is as resilient as it could be as a result.”

Mrs Preece added: “Our hypothesis is that if farmers can use red clover in mixed leys then they can have all the benefits without any negative consequences. There might even be a positive effect on fertility because such leys offer high feed quality.

“We hope that by updating the science we can give farmers the confidence to use red clover again, and vets the confidence to encourage it."

As well as its nutritional benefits to the soil and the sheep, red clover also scores high politically – legume and herb rich swards are currently part of England's Countryside Stewardship schemes, attracting £309/ha, and are likely to be part of most Environmental Land Management Schemes.

The field lab is being run through the Innovative Farmers programme, which is managed by the Soil Association, with the first results expected in early January 2022.

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