1922.] 



Diseases of the Swede Crop. 



1093 



as we have seen, Arthur Young thought it wise to insist many 

 years ago. Whereas, however, most farmers are, or believe 

 themselves to be, good judges of horses, they are rarely good 

 judges of tractors : and the points of a tractor cannot be 

 summed up in the same way. If the tractor is to be the power- 

 unit of the future it will be necessary to take a leaf from the 

 book of the users of commercial motor vehicles, and award 

 prizes for well-kept engines as well as good ploughing. Such 

 competitions, provided the drivers are contented and take a 

 pride in their work ("which will only be the case if they are 

 contented), may work a charm not very different from that 

 which the early ploughing matches are reported to have done 

 in improving the work of ploughmen: for the bane of the 

 tractor is the repair bill, and the way of escape is a fuller 

 understanding of the machine, a higher craftsmanship. As for 

 judging between tractor and tractor, that is a matter for pro- 

 longed test and scientific study, and if the farmer is to form an 

 independent opinion he must be guided largely by independent 

 reports. 



****** 



DISEASES OF THE SWEDE CROP IN 

 CUMBERLAND AND WESTMORLAND 



IN 1921, 



R. B. Strang, N.D.A. 

 Ministry of Agriculture. 



Powdery-Mildew of Swedes. — One of the most prevalent dis- 

 eases of swedes throughout the country last year was powdery- 

 mildew* and in the northern counties the attack wds un- 

 usually severe. In the early part of the summer, 1921, the 

 swede crop in practically all parts of Cumberland and Westmor- 

 land looked exceptionally healthy and vigorous, and promised, 

 in spite of the drought, to be an excellent crop. About the 

 middle of August, however, mildew developed and after that 

 date the disease steadily became worse and the crop received 

 a severe check Not only were the older leaves affected, but the 

 young leaves became mifdewed before they attained any great 

 size. Rain fell copiously in August, so that the damage to the 

 crop may be regarded as due to mildew and not to drought. 



* Another mildew frequently attacks swedes, namely the False Mildew, 

 caused by the fungus Peronosjjora parasitica. This disease is more prevalent 

 in wet seasons and may cause much destruction of the foliage 



