“Confusion” Among U.K. Grassland Experts

Press, Volume C, Issue 29518, 20 May 1961, Page 9

“Confusion” Among U.K. Grassland Experts

Disappointment with the general picture of herbage production on British farms was expressed at the Lincoln College farmers’ conference by Professor T. W. Walker, professor of soil science, who returned to the college late last year after a stay of about two years in Britain. “I think it is because of the utter confusion among the various ‘experts’—agrostologists, soil chemists, and fertiliser firms,” he said. “For instance, at the International Grasslands Congress in Reading, Dr. W. Davies, Director of the Grasslands Research Institute, in one and the same breath called white clover a weed, and said that we must rely on grass and white clover associations and that he wants to see British farmers using the equivalent of a ton of sulphate of ammonia to the acre on their grass. The last two objectives are hardly compatible.” said Professor Walker.

“A few farmers are relying on clovers as their major source of nitrogen, but an increasing number, particularly of small dairy fanners, are forgetting clovers and using heavy dressings of nitrogen fertilisers and most are making little use of either. ‘There is a lot of nonsense talked in Britain about the climate not suiting clover and that clover will not fix as much nitrogen as in New Zealand. In New Zealand we give all credit to the climate for grass growth, but in England they point to the

climate as the reason why they cannot grow clovers. “In some of my own experiments in Britain clovers have fixed some 2001 b of nitrogen an acre, which is very similar to the best Canterbury figures. One of the troubles is that much of the grassland is so devoid of clovers that nitrogen fertilisers are really necessary. “There is no question that nitrogen will stimulate production where clovers are weak, and unfortunately most experiments to test the value of nitrogen are carried out on such swards. In some cases this is because experimenters have never grasped the first principles in herbage production and in others because fertiliser firms want to promote the use of nitrogen.

“It was heartening to meet a few research workers who have ‘seen the light’ and who are showing what clovers can do if given a chance. The results of one such experiment in Northern Ireland demonstrate a point that I have been pressing for a long time—that to use two to three hundredweight of a nitrogen fertiliser on a really good grass-clover sward merely pushes up grass yields, depresses clover yields and scarcely affects total yield. Yet these quantities of nitrogen, where it is used at all, are probably the commonest levels applied. “What most advisers and farmers have not grasped is that to improve herbage production greatly they must either use more nitrogen or learn how to grow clovers.”