News

28/07/2011

Cover Crops

This has been a difficult year for cover crops.  In most parts of the country, the spring drought led to seedbeds almost devoid of moisture, leaving a difficult question of timing.  The danger of sowing maize in mid May is that the plants develop with less lignin in the stem walls and there may then be a problem of lodging later in the year.  Most of those crops of straight maize planted in April established reasonably well, although there was variability where soils were short of moisture.    For cover crop mixtures, the general advice at the time was to wait for rainfall before sowing, especially those containing brassicas.

The weather broke in mid-May giving an opportunity to plant cover crops and Environmental Stewardship mixtures.  Listening to reports of the growth of cover crops, there seems to be an east/west divide, coinciding with the amount of spring rainfall.  In the west where moisture was adequate, they have established reasonably well.  From the east however, especially East Anglia and Kent, have come stories of variable germination and patchy growth.

Flea beetle is always a problem on brassicas.  Advice should be taken from a qualified agronomist, but an effective seed dressing is usually considered essential.  Even then further application of an insecticide may be necessary to counter the threat.  Flea beetles are active in the warmth of the day not at dawn or dusk, so the middle of the day is the time to look for them to decide whether action is required.  This year slugs, too, have caused some damage whilst, for established crops, pigeons now represent the main threat.

It was noticeable at the recent French Game Fair at the Chateau de Chambord in the Loire valley that there were no stands selling seed mixtures for cover crops.  But then, one rarely sees cover crops growing in the French countryside.  There are few organised shoots with thousands of bird released as we have in England and thus the requirement for cover is much reduced.

However, there are crops of quinoa and sorghum grown in the Loire valley, but for grain rather than game cover.  Quinoa, the 'grain of the Incas', has been cultivated for thousands of years on the plateaux high in the Andes.  The many tiny seeds produced are high in fibre, protein and minerals but have no gluten, so are good for those who are gluten intolerant.  Like meat but unlike most other plant species, they also contain the amino acids that the human body cannot produce and are thus excellent in a vegetarian diet.

It has taken twenty years of research to breed varieties that are suitable for European conditions and the area sown in the Loire has doubled this year to over 200 hectares.  Of the 6,000 to 7,000 tonnes consumed in Europe each year, half of that in France, most is imported from Bolivia, but it is now hoped that more can be home grown.  The small pale grains, not a cereal but a member of the spinach family, are used in risottos, salads and couscous type dishes.

Quinoa is mostly grown in the UK in a mixture with other species for game cover and Environmental Stewardship mixtures.  David Bright of Bright Seeds says that it is particularly useful as it stands well and produces thousands of small seeds that drop steadily to the ground during winter providing high protein feed for game and other farmland birds.  He uses a variety called Red Carina, grown for him in the Czech Republic and exclusive to Bright Seeds, which is high yielding and stands throughout the winter.  The red colour stands out from the other species with which it is grown, such as triticale, kale, sorghum and rape.  Along with others crops, seed will be in short supply this year after two years of dry seasons in Europe.

Given the variability of the establishment of cover crops this season, there may be shoot managers who are concerned that they have insufficient cover for the coming season.  There are still some excellent options available, fast growing species and mixtures that can be sown even in August, provided there is sufficient moisture in the seedbed.  Mustard, stubble turnips, forage rape, fodder radish and kale crosses are all single species that can be successful from summer sowing. 

Utopia, a cross between black mustard and a wild Ethiopian kale, has proven over recent seasons that it is the fastest growing option and provides excellent cover throughout the winter.  It is exclusive to Bright Seeds, as is Autumn Promise, a mixture that includes buckwheat, kale, vetch, fodder radish, mustard, rape and Utopia.  Swift is a cross between rape and kale and is sometimes planted after grass for cutting or summer grazing has been ploughed in.

Correct preparation is just as important with a late sown crop as with those planted in spring or early summer.  Seedbeds should be fine but excess tillage should be avoided in dry weather to maintain moisture in the soil.  Drilling is usually more successful than broadcasting and rolling behind the drill can also be beneficial. 

Seed dressing to control flea beetle on brassicas in the early stages is likely to be essential and fertiliser will help to obtain rapid growth.  Of course, solid fertiliser needs moisture to become available to the plant so a liquid foliar feed will be more effective in dry weather.  Many established crops suffering from drought stress and low temperatures were given a boost by applications of a product such as 'croplift'.

If large numbers of pigeons tuck into a cover crop, they can cause a lot of damage very quickly.  There are always those looking for opportunities for shooting at this time of year but, if no-one is available, bird scarers of one sort or another may help.  At the Bright Seeds trial plots, a kite has done an excellent job in keeping the pigeons at bay.  Christopher Bright was so pleased that he acquired a number that are now for sale.

So, even at this late stage, there is no reason for panic over the lack of effective cover crops for the coming shooting season.  There are options available but, the sooner any crops are sown, the greater the chance of success.

Andrew Davis

July 2011

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