450 Journal of Agricultural Research voi. xii. No. ^ 



the senior writer, that the malady was observed by him during 191 6 at 

 Creedmoor, N. C. To judge from the additional fact that the disease has 

 been collected during the past season in 19 counties within North Caro- 

 lina (Surry, Stokes, Forsythe, Guilford, Rockingham, Caswell, Alamance, 

 Orange, Person, Durham, Chatham, Moore, Hoke, Wake, Johnston, 

 Franklin, Granville, Vance, and Warren) and in 3 within Virginia (Pitt- 

 sylvania, Halifax, and Mecklenburg) it is highly probable that the disease 

 existed prior to the present year. Whether or not this disease occurs in 

 other of the States in which tobacco is grown is not known, except in the 

 case of Wisconsin. A letter from Prof. James Johnson, Department of 

 Horticulture, University of Wisconsin, who has had occasion to observe 

 the disease in North Carolina, states that a similar bacterial spot, although 

 not nearly so destructive as in North Carolina, has been observed by him 



in Wisconsin. 



ECONOMIC IMPORTANCE 



The disease is universally conceded by growers of tobacco to be the 

 most destructive one which attacks this crop. Losses, ranging from 

 those which were inappreciable to those in which almost the entire crop 

 was destroyed, were sustained in every locality where the disease was 

 present. In some instances fields upon the same farm were observed 

 to be badly affected, while others had little or none of the disease. In 

 some sections, too, the disease occurred upon every farm within a radius 

 of several miles, while in others it was present only in an occasional 

 field. It is not possible, therefore, because the disease was not uniformly 

 destructive over the entire area in which it is known to occur and because 

 time has not been afforded to make a careful survey, to obtain a reasonable 

 estimate of the damage wrought. Some idea of the losses, however, can 

 be gained from statements taken from reports kindly furnished by a 

 number of growers, who compared their leaf-tobacco sales with neighbors, 

 whose crops were free from wildfire or were at most only slightly affected. 

 Some of these reported losses averaging $100 per acre for their entire 

 crop. One correspondent estimated his total loss at $5,000 and said 

 that hundreds of farmers in his section suffered an equal acreage loss. 



APPEARANCE OF THE DISEASE 



The disease was first noted early in June during a period of rainy 

 weather accompanied by nights which were so cold as to retard the 

 growth of tobacco. The affected plants in many fields perished, necessi- 

 tating replanting a second or a third time. A period of relatively dry, 

 warm weather of about a month's duration followed, during which time, 

 the crop made an extremely rapid growth, as shown by the fact that the 

 plants were sufficiently mature to be topped. At this stage of their 

 development another rainy season of about a week's duration occurred 

 and was followed by another epidemic of the disease. The disease 



