The Bulletin 63 



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 sample of seed that he might determine whether they were suitable for sow- 

 ing or not. The result was that only one man sent a sample of his clover seed 

 in to be tested. This fall thousands of acres were planted with spores which 

 will be ready to cause the disease next spring, all of which could have been 

 prevented. 



Nearly all diseases of the more important crops can be prevented by using 

 a small amount of time and money and a little thought. Take, for instance, 

 the oat smut. The oat crop of North Carolina is diminished from 10 to 40 

 per cent annually by this disease alone. The cost of producing oats under 

 ordinary conditions is about $9.00 per acre. At the average selling price it 

 would take 22.5 bushels to break even. The average yield for North Carolina 

 is about 20 bushels. Thus you can see the average farmer is growing oats at 

 a loss, not saying anything about the large number who are producing less 

 than the average. Ordinarily, when preventive measures have been taken the 

 crop yield was increased 20 per cent. This increase of 20 per cent over 20 

 bushels would bring the average yield up to 25 bushels per acre. At this 

 rate the farmer would not only raise oats at cost but would realize a net 

 profit of two and one-half bushels per acre. Oat smut, as a rule, can be 

 almost entirely controlled by treating the seed with formalin in the following 

 way. One pint of formaldehyde to thirty gallons of water will make a solu- 

 tion sufficiently strong to kill all smut spores. There are two ways of apply- 

 ing the formaldehyde solution. The first, and a little the cheapest, is by 

 spraying the seed. The grain should be spread out rather thinly over a 

 smooth surface, such as a barn floor, canvas, or hard ground. The mixture 

 should be sprinkled thoroughly over the grain. Then mix the grain well 

 and heap in a pile. Cover the pile with old carpets, canvas or anything that 

 will prevent the fumes from escaping. The fumes from the formaldehyde 

 are as deadly as the solution itself. Leave the seed covered about six hours 

 and then dry. In the second method the grain is immersed. This can be 

 done by dipping a sack of oats into a barrel containing the same strength of 

 solution as used in the former method. The sack should be left in the barrel 

 about ten minutes. Then drain and put the wet sacks of grain in a pile and 

 cover as in the first method. It should be left covered about two hours. 

 The seeds should then be dried and sown. Formaldehyde costs about thirty 

 cents a pint and one pint will be sufficient to treat 30 bushels of grain. It 

 only takes a thinking man to see that this is a good plan to increase his oat 

 crop at least one-third. 



The average yield of cotton is diminished from 10 to 40 per cent by plant 

 diseases. The one causing the greatest amount of loss is anthracnose or boll 

 rot. The spores of cotton anthracnose are disseminated largely through the 

 seed. They can live in the seed at least three years and it is unwise to plant 

 seed after they have attained that age. The spores will remain in the old 

 stems and bolls for twelve months. Therefore, in controlling the disease, 

 there are two important measures. First, practice at least a two year crop 

 rotation. Second, select uninfected seed. Seed should be selected at picking 

 time from bolls that show no signs of infection of any sort. The boll should 

 be large and contain characters needed in improving the variety. The cotton 

 picked in this way should be ginned after all other ginning is done and the 

 gin disinfected. If it is too much trouble to select cotton seed for the entire 

 field, a small amount may be selected and used for starting a seed plot. The 

 proper selection of seed not only controls the anthacnose but improves the 

 variety year by year. No man can afford to raise cotton and not follow out 

 the two methods mentioned above. 



Corn suffers less from diseases than does any other crop. Corn smut 

 probably lowers the yield of corn more than any other disease. The only 

 control measures for corn smut are crop rotation and field sanitation. Keep 

 the smutted stalks and ears from getting into the manure. Seed selection 

 always improves corn, yet a very small amount of smut can be gotten rid of 

 in this way. 



The potato crop often suffers from diseases that are largely preventable. 

 Probably the most serious disease of the Irish potato, especially in the west- 

 ern part of the state, is the late blight or downy mildew (Phytophthora in- 

 festants). The disease appears late in July. It affects the stems, leaves, and 

 tubers. Protective spraying with bordeaux mixture will entirely control the 



