MAIZE. 



127 



spread from a single infected plant contaminating the soil in the vicinity is 

 probably far more important. Areas where the disease lias appeared 

 consistently year after year may increase in size. The percentage of infection 

 on lands where Head Smut is prevalent varies greatly, and. is probably 



influenced by soil moisture conditions. 



Head Smut of Maize {Sarosporium reiltanum). 



Control. — The methods of control recommended are : — ■ 



1. Obtain seed from uncontaminated cobs. 



2. Do not grow maize continuously on the same land. Sorghum is liable 

 to attack, and is not to be regarded as a suitable rotation crop. The spores 

 probably persist in the soil for some years, so that, on infected land, the 

 rotation should not include maize and sorghum too frequently. 



3. Early removal of smutted heads before they have burst and scattered 

 their spores widely. They should be collected in a tin or similar receptacle 

 and burnt. If more care were taken in small maize oops in the collection of 

 smutted heads, a great deal of smut could be eliminated. 



