WHAT IS A PERFECT STAND? 171 



5- Notice that the proportion of stalks having suckers decreased 

 rapidly and regularly with the increase in thickness of planting. 



6. The average of all the experiments shows that the proportion of 

 barren stalks increased with the increase in thickness of planting from 

 4.2 per cent where there was only one stalk per hill, to 10.7 per cent 

 where there were five stalks. 



7. The proportion of stalks affected by smut was greatest where 

 the thinnest planting was practiced. 



8. The proportion of seed ears decreased rapidly and regularly 

 with the increase in thickness of planting. 



9. In the summary of all the experiments the proportion of 

 nubbins and worthless ears was lowest where there was an average of 

 one stalks per hill. The proportion of nubbins and worthless ears 

 where the thin planting was practiced was probably due to the fact 

 that many of the stalks produced a second small ear and that some 

 of the many suckers had small ears on them. 



The increase in the proportion of nubbins and worthless ears 

 with the increase in the thickness of planting was greater in the 

 southern section than in the central and northern. The increase 

 in the proportion of barren stalks was also greater. These results 

 show that thick planting decreases the productiveness of the stalks 

 more in the southern part of the state than it does in the northern 

 section. 



WHAT IS A PERFECT STAND? This question is so often 

 asked that it is here partially answered. 



On Rich River Valley Soil. It is only during a season of compara- 

 tively little rainfall that the farmers on the river lowlands are able to 

 grow a crop at all. At least three to four stalks per hill should be 

 the standard on such land. (See foot note.) 



Upland Thin Soil. At Institutes and Short Courses one quite 

 often hears the remark that as many stalks cannot be grown to the 

 hill now as 20 or even 10 years ago. The fact that the virgin fer- 



SOUTHBRN IOWA BOUGH LANDS. 

 Those are underlaid with hsrdpan, and in a dry year two stalks per hill would be suffi- 

 cient. A lack of plant food and the fact that the com roots cannot penetrate 

 the sub-soil to secure moisture, requires a smaller number of stalks per hill. 



NORTHERN IOWA, LOW, DNDRAINED SOIL. 

 The years of shortage in early spring precipitation are a boon to the corn growers of 

 the northern area of the Wisconsin Drift. Three stalks or even more should here 

 he the standard, because tlie soil is well stocked with potential and available plant 

 food. 



