Lucerne is ideal forage crop for organic cows
Home-grown forage crops are central to the success of
organic farming systems. Marianne Curtis went along
to an alternative forage open day to find out more about
how to get the most from these crops
WITH its high yield and high protein characteristics, lucerne provides the ideal forage crop for one organic dairy herd in Glos. However, it has taken some years to perfect the growing technique for this unusual crop.
Simon Tomlinson, who runs three farms near Westonbirt, grows more than 121ha (300 acres) of lucerne for his 340 dairy cows, which are run as three separate herds, and polo ponies. Hosting a recent Soil Association open day on alternative forages and organic grassland management, he shared his experience of growing lucerne with other organic producers.
"It is the key to our forage production. Our soil type varies from Cotswold brash, brash and loam to Oxford clay. Lucerne is difficult to establish on clay because dry soil is required and sub-soiling is necessary as there must be no compaction. However, when you do manage to establish it on clay, it dramatically improves soil structure."
Lucerne is planted for four years as part of the farms arable rotation. In the first year, it is established under wheat. "Lucerne is sown in the first week of May as part of a mix which contains 0.5kg red clover, 1kg white clover, 2.5kg perennial ryegrass and 9kg lucerne/acre.
"This is the earliest that it can be sown because it is susceptible to frost. Including clover and ryegrass in the seed mix reduces competition from weeds. Wheat is sown about a week later. It improves yield and allows arable area aid payments to be claimed."
First year lucerne was flowering at Mr Tomlinsons farm during last weeks open day, and he said that this was the best time to cut it. "Waiting until lucerne flowers before cutting allows it to build up energy reserves in its roots meaning it to recovers more quickly following cutting."
The arable silage formed from this lucerne/wheat mixture yielded 18t/ha (7t/acre) last year with an analysis of 48% dry matter, 10.3% crude protein, 11.5ME and D value of 74.4.
In subsequent growing seasons, lucerne can be cut when in bud and Mr Tomlinson aims for three cuts a year which gives a total yield/ha of 32-35t (13-14t/acre). However, it shouldnt be cut or grazed later than the end of September, he advised.
"This allows good growth before the first frost. Once well grown, it can be grazed off but avoid poaching."
Lucerne forms part of cows winter ration which also contains maize silage, field beans and some permitted non-organic concentrate. "Yields are 5000-6000 litres/cow/year, but a change in organic regulations mean that we will be able to feed bought in concentrate when it is most beneficial, such as in early lactation, which should permit better yields than under the present system where it must be fed seasonally."
Although a good source of starch, maize has proved more difficult to grow on the farm than lucerne. "We grew a good crop the first year when non-organic seed was permitted but have fought a downhill battle against rooks since. I wish someone would invent an organically approved seed dressing such as curry powder or something that birds dont like."
But preparing a good seed-bed and drilling maize to a depth of 10cm (4in) can help, he believes.
Lucerne is the ideal forage for Simon Tomlinsons 340 dairy cows.
• Sow early May or later.
• Cut after flowering in year one.
• Graze only after first frost.