48 



A Clover Fungus. 



With regard to methods of preventing this attack, and 

 remedies for it, it is recommended by most writers that 

 clovers should not succeed clovers for several years where 

 there has been infection. And where this disease has 

 attacked young clovers, the ley should be ploughed up it 

 possible after the first cut, and before the sclerotia send 

 forth ascospores which may be carried by the wind'to infect 

 fresh fields. Professor Chester, of the Delaware College, 

 remarks that, the fungus being one which only lives under 

 shady, moist conditions, such as exist under dense growths 

 like grass for hay, and clovers, and one which is soon 

 destroyed by air and sunlight, it is evident that open cultiva- 

 tion and frequent stirring of the soil, such as prevail in the 

 growth of corn, potatoes, tomatoes, and vegetables, will best 

 enable the farmer to eradicate the fungus.* Since this 

 fungus can live and propagate on so many species of 

 leguminous plants, it is highly important to prevent the 

 germination of the sclerotia and the development of the 

 Botrytis form. Dr. Ritzema Bos advises that when clovers 

 are seen to be infected in patches in the early stages of the 

 disease, the diseased plants with the soil round and near 

 them should be dug up and burned. It is desirable to keep 

 trefoil out of mixtures, as strongly advised by Professor 

 Rostrup. This is not by any means an indispensable clover. 

 It is also advised by Rostrup and others that a good pro- 

 portion of rye grass and other grasses should be sown with 

 clovers when there is any fear of infection. When clovers 

 are seen to be attacked it would be desirable to feed them off 

 with sheep, and plough the land deeply after folding. Or 

 the first cut might be made into hay, and the second growth 

 folded off, and the land ploughed at once. There is no 

 suggestion made by any writer on this fungus with regard to 

 application, either in powdered or liquid form, of manures 

 and remedies to prevent plants from infection, or to check 

 its spread. Obviously, from its habits and life history, such 

 applications would be inoperative, unless the plants were to 

 be sprayed in the early autumn with a bouillie bordelaise ; 

 but the plants would be small at that date, and it w^ould be 



* r/A, p. iio. 



