70^ Report of the Botanist of the 



The eulpliur-lime treatment is recommended whenever the Iosb 

 from smut is as much as one-third, of the crop. The treatment 

 would be greatlj facilitated and cheapened by the construction of 

 a drill which will apply sulphur, lime and seed at one operation. 

 It is further recommended that onion growers investigate the 

 transplanting method; also try to develop the culture of gome 

 other crops to rotate with onions. 



NATURE OF ONION SMUT. 



Smut is a fungous disease which attacks onions grown from 

 seed. The fungus causing it, Uroci/stis oepulm, is related to the 

 grain smuts, but different from them. So far as known the 

 onion smut attacks no other plant than the onion. It kills great 

 numbers of the seedling plants soon after they come out of the 

 ground; and many other plants not killed outright by it are much 

 injured, so that they die later or produce small and misshapen 

 bulbs which are liable to rot. 



If a seedling onion plant affected by smut be examined the 

 affected leaves will be found to be not only enlarged but often 

 distorted and if the smut is nearly mature the leaves will appear 

 abnormally dark in color and often show black streaks. Upon 

 breaking open the leaves they are found to contain a black pow- 

 dery mass which is composed of the spores of the onion smut 

 fungus. These black masses of smut spores also occur on the 

 bulbs. 



AMOUNT OF DAMAGE DONE. 



Smut la, perhaps, the most destructive of all onion diseases 

 and is common in nearly every section where onions are grown- 

 extensively. There are, however, localities where it is unknown. 

 In this State it is very troublesome in the onion fields of Orange 

 County while in the Madison County onion district it appears to 

 be wholly absent. 



It usually does not become destructive in a field until after 

 onions have been grown for several years in succession. When 

 onions are grown continuously on the same land the smut grad- 



