Herbs prove popular way to increase biodiversity

Chicory isn’t just the poor man’s coffee or the posh man’s salad ingredient – it also offers dry matter yield, drought resistance and anthelmintic properties for hard-up dairy farmers.

And it’s one of several herbs being re-introduced to increase the diversity of monoculture grassland.

While travelling for a Nuffield scholarship, Cornish organic dairy farmer Ben Mead found native, lower yielding plants had given way to highly bred ryegrasses around the world. Yet deep-rooting herbs can pay handsome dividends in both yield and quality when used to broaden biodiversity, he says. Some organic farms using up to 70 herbs to create medicinal paddocks have claimed cheaper, faster cure rates than conventional medication.

“Biodiversity buffers harvest from the climate – hedgerows rarely suffer drought. In Australia and New Zealand, farms incorporate wide ranges of suitable plants – such as comfrey, chicory, yarrow, burnet, and alsike – into pasture, or plant them along cattle track fence lines.”

Chicory and plantain are two herbs benefiting from modern plant breeding. The result is herb varieties that can improve grazing swards reliably and consistently. Birdsfoot trefoil is a non-bloating clover so it has potential, but there is still variation between available varieties, says Paul Billings of British Seed Houses, which sells the Kiwi-bred Puna ll chicory and Ceres Tonic plantain.

Mr Billings thinks herbs were forgotten as ryegrass and nitrogen took off. Chicory, though, fits in easily as it competes well with ryegrass, grows under nitrogen and benefits from a tight paddock rotation. Its deep tap roots (over 30cm) unlock minerals that are unavailable to shallow rooting species. “This results in a better mineral uptake in the animal. The long tap root also means plants can grow during a drought and it helps improve soil structure: Tap roots are strong enough to break through plough pans.”

In New Zealand, both chicory and plantain are often grown as pure swards. However, Mr Billings recommends sowing chicory as part of a ryegrass/clover mix, making up less than 30% of the sward dry matter to avoid milk taint. A seed rate of 0.75kg/acre should suffice in 13-14kg/acre of a grass/clover seed mix.

He explains chicory grows from a single growing point – a crown – and if this is damaged it can kill the plant. Grazing when conditions are wet, or during its dormant period (November to February) can cause damage. “Chicory works best under a three-week rotation, otherwise it can bolt and flower blue – and it’s a big plant at four foot. The stems are hollow, so if it has to be topped and water gets in that can also kill plants.”

Under general grassland management, chicory is expected to persist for up to five years. Australian trials have also found higher milk yields in cows grazing chicory (19 litres/day) compared with cows on ryegrass paddocks (10 litres/day). And practical farm experience from New Zealand reports dry matter yields of 8000kg/ha in the first season. A 2ha block of 100% chicory was strip grazed by 680 cows near Hamilton, in 3-4 breaks. In its second season, it still produced about 6000kgDM/ha, outstripping grass in what was a drier year.

Case study

Anthelmintic properties and mineral content prompted organic producer Tim Downes to drill chicory and plantain into grazing three years ago. Almost 40ha (100 acres) of grazing at the farm near Longnor, Shropshire, are now herb pastures for the 170-cow dairy herd, plus followers and beef cattle.

“We wanted herbs for rearing baby calves on clean pasture, the high tannin levels control worms. The other advantage is mid-season growth: On our clay land we can dry up in summer between June and August. These plants are all deep rooting. We saw how well it grew and survived our cut and silage rotation, and it’s gone on from there,” says Mr Downes.

He says cows find the herbs palatable and there has been no milk taint. “These herbs suit anyone who is looking to produce grazing on a field during summer months when it’s drier. Chicory will cope with quite tough paddock grazing from March to November – this encourages it to stay in the sward.”