48 EXPERI:M]:XT station. [Jan. 



planting. We are inclined to think from our observations that 

 fully 80 per cent, of the diseased plants, ijarticularly in this 

 locality, may be traced to improper transplanting. It has been 

 shmvn that when the roots are lacerated in any way the trouble 

 may gain a foothold, as the metabolic or life processes are thus 

 deranged, and a condition favorable to the disease is introduced. 

 We have found that when the roots are broken or torn to any 

 great extent in removing the plants from the seed bed they are 

 often liable to become diseased. With regard to this point we 

 may quote from a Coimccticut station report : — 



In this connection Mr. Barnes of Hatfield related the following: 

 " Young plants wei-e taken from the same seed bed by two different 

 farmers, and although the soil of the fields was the same, one farmer 

 had many mosaic jiLants in liis field and the other had almost none. 

 Inquiry revealed the fact that one farmer took the plants from the 

 seed bed when it A\as quite dry, the other Avhen it was well moistened. 

 In taking the plants from a dry bed one cannot help lacerating the 

 roots, while from a well-moistened bed the roots may be drawn in an 

 almost intact condition. Lacerated roots do not generally develop to 

 such a vigorous state as is required by a quickly gi'owing tobacco 

 plant." 



We made experiments in regard to this point and the above 

 observation was veritied. In the majority of cases of the dry 

 plants a large percentage developed the disease. The remedy in 

 this case suggests itself, that is, the seed bed should be in moist 

 condition when the plants are removed, but not so wet as to 

 have any adhering ball of earth on the roots ; but this condition 

 is rarely found, as very little soil remains on the roots when 

 they are taken from the seed bed. 



After the disease appears in the field it is practically im- 

 possible to control it, l)ut it does not usually make its appear- 

 ance on plants not affected in the first few weeks of growth. 

 Mild cases of this trouble sometimes appear when the flower 

 bud is left on, as has been shown by A. F. Woods, and the 

 mottled appearance often shows on ])lants which have been 

 topped on the subsequent growth, i.e., the suckers. Soils of a 

 compact, clayey character also sometimes induce the disease in- 

 directly by requiring constant close cultivation to prevent pack- 



