210 



FUXGI AXD PUXGICIDES 



though by no means always, on soil of a character some- 

 what different from the rest of the field. It seems hard . 

 to designate what special condition or quality of soil is 

 most usually associated with the disease; but, uj^on the 

 whole, it is found in the rich spots, rather than in those 

 of the poorer quality. In many cases it is upon the 

 lowest ground, whether or not water has temporarily 

 stood in the hollows. The most definitely bounded area 

 noticed was upon a spot which had, until the year previ- 

 ous, been too wet for tillage, but which had been tile 

 drained and broken up, the sod having rotted. 

 But ordinarily there are no such definite borders to the 

 infected areas, and often nothing whatever to suggest a 

 reason for their peculiar distribution. 



^•IJlDon closer observation it is found that young 

 diseased plants, besides being smaller than the healthy 

 ones, are uniformly yellowish in color, the lowest leaves 

 showing ^orst. As death overtakes these leaves, they 

 apparently succumb by a general decline from the 

 healthy state, and rarely die, and wither chiefly at the 

 ends and margins as in some other cases. When some 

 of the affected plants are pulled from the ground they 

 are found to give way too easily, in consequence of the 

 death, to a greater or less extent, of the oldest and low- 

 est roots. In anything like severe cases at least one-half 

 the roots — always the lowest — are injured, and usually 

 dead. The bottom portion of the stalk is likewise 

 affected, and will be found dead or dying. If spht lon- 

 gitudinally through the middle, the inuer tissue of this 

 lower part is seen to ha.ve a uniform dark color : and a 

 similar discoloration, gradually becoming less and less 

 pronounced, appears in the next succeeding nodes, or 

 joints, while the spaces between them (internodes) are 

 seemingly healthy. On the surface, Tvhen carefully 

 freed from dirt, brownish, corroded spots can be found, 

 sometimes strictly bordered, again diffusely spreading. 



