SPECIAL REPORT FOR YEAR 1912. 43 



DISEASES OF CEREALS AND FOR-\GE CROPS. 



The Station pathologists have made some quite extensive field 

 observ'ations upon the distribution of oat diseases in the State 

 during the past summer. An apparently new leaf blight disease 

 of oats has been found which seems to, be very generally dis- 

 tributed throughout Maine. Not enough is known about it as 

 yet to suggest methods of treatment or prevention. It is appar- 

 ent, however, that it does considerable damage and that a large 

 number of varieties are quite susceptible to it, although some 

 are probably more resistant than others. 



Oat smut was found to be much more common and destruc- 

 tive in the State than was at first supposed. In some cases 

 10% to 25% of the crop was destroyed in this way. This is, 

 perhaps, the most conspicuous illustration of the need for 

 demonstration work in plant patholog>'. A perfectly successful, 

 cheap and effective method of seed disinfection is known, 

 and it can be carried out by any man of average intelligence. 

 To do this the oats to be treated are spread out on a canvas 

 or clean bam floor and are sprinkled with a solution of one 

 pint of formaldehyde to 40 or 50 gallons of water at the rate 

 of a gallon per bushel, and then shoveled over to insure thor- 

 ough wetting of each seed. Cover with a blanket or canvas 

 for at least four hours, but not longer, and then spread out to 

 dry. 



One of the serious obstacles to growing alfalfa in Maine 

 appears to be the alfalfa leaf-spot. Many specimens of this are 

 received and practically all fields examined show bad attacks 

 of the disease. No practical method of controlling it has been 

 developed, but frequent cutting is said to help. Even though 

 alfalfa is a valuable forage crop it may be wiser to turn atten- 

 tion to the more hardy red clover, which reaches its highest 

 perfection of development in Maine. However a new disease 

 of red clover was found in Alaine last season. This is an an- 

 thracnose and is apparently similar to one described in Ten- 

 nessee for the first time a few years ago. How wide-spread 

 and destructive it is has not been determined but some sections 

 of the State were found to be free from it. 



