Rural School Leaflet. 



771 



half hours. Remove, cut, and plant. Care should be taken that the 

 tubers so treated are not placed in crates or sacks or other receptacles 

 that have had in them scabby potatoes. It will be best to wash 

 out the basket or crate in which the treated seed is to be put, with 

 the formalin solution left in the tub. Plant the treated tubers in one 

 or more rows by themselves. Then, cut and plant the other half bushel 

 of untreated tubers in rows alongside the treated ones. Mark the 



Fig. 79. A young experimenter 

 (Superintendent Kern, Illinois) 



treated and untreated rows with stakes. Give all of the potatoes the 

 same sort of care and cultivation throughout the season. When the 

 potatoes are ripe, dig the treated and untreated rows separately. 

 Make a careful count of the scabby potatoes in an equal number 

 of bushels from the treated and untreated rows, taking them just as 

 they come in digging. Make a count also of all the potatoes in the 

 bushels taken, and calculate the percentage of diseased potatoes in the 



