germinating by the formaldehyde. The presence of these two variables made the 

 interpretation of the yields very uncertain. An effort was made in the experiments 

 of 1923 to determine to what extent each of these factors was responsible for the 

 variation in yield. This was accomphshed by first determining the extent of the 

 chemical injury. During the third or fourth week after planting, when it was 

 thought that practically all the plants which would come up were visible and before 

 any of them had disappeared from smut or damping off, the number of plants in each 

 row was determined irrespective of whether they were diseased or not. Compari- 

 son of these with the untreated rows determined the extent of the chemical loss. 

 The relative amount of loss from smut was determined at harvesting by subtracting 

 the number of sound bulbs from the number of seedUngs which escaped chemical 

 injury. It is not thereby assumed that all the plants which died in the interim were 

 killed by smut but that other agencies acted equally on all the rows. Also in order 

 to check up under field conditions the influence of soil moisture at planting time, the 

 percentage of moisture in the soil one inch below the surface was calculated for each 

 experimental field on the day of planting. 



Allen Clark Farm Experiment, 1923 



This experiment was located in North Amherst on land heavily infested with 

 smut at one end but very lightly at the other. It included 28 rows, 283 feet long, 

 13 inches apart, seeded at the rate of six pounds per acre. The ground was fairly 

 moist, containing 17 per cent, water with a retentive capacity of 65 per cent, of the 

 dry weight. It was planted on April 27 and there were heavy rains on the 28th and 

 29th. The rain probably came soon enough to affect the results of the treatment. 

 Inspections while the onions were coming up and comparison by counting the seed- 

 lings at the end of a month showed the chemical injury to be neghgible in this field. 

 On September 4, when the onions were ready to harvest, the sound bulbs in 100 feet 

 of each row on the more heavily infested end of the field were counted. The results, 

 presented in Table VI (p. 28) are about what might be expected when the soil was 

 neither extremely dry nor extremely wet. The laighest yields were secured with the 

 formulas of medium dilution (1-64-3000, 1-75-3000) or where the rate of distribu- 

 tion was medium (1-50-4000). None of the formulas failed to control, but the 

 1-50-5000 was least satisfactory. The appearance of the field four weeks before 

 ha' vesting is shown in Fig. 2. 



Kuzmeski Farm Experiment, 1923 



This experiment was on the same field as the experiments of 1920 and 1922. It 

 consisted of 24 rows, 436 feet long and 13 inches apart, seeded at the rate o"" six 

 pounds per acre on April 21. The soil was extremely dry and dusty. A high wind 

 during the day and the succeeding days kept the upper layer in the same condition 

 for a week. The moisture was 6 per cent, and the retentive capacity 45 per cent, of 

 the dry weight of the soil. All conditions were ideal for a high percentage of formal- 

 dehyde injury. 



Examination when the onions were coming up and counting the number of seed- 

 Ungs when it was judged that all had come up, showed that the injury was certainly 

 all that was predicted. On September 3 the number of sound bulbs remaining were 

 counted. The data on this experiment are summarized in Table VII (p. 29). 

 These data show that there was severe injury with all formulas used. The 1-50- 

 5000 formula caused the least loss but that was 20 per cent. Even when the solu- 

 tion was diluted 1-100 there was a loss of 36 per cent. It is doubtful whether any 

 practical formula can be used under these very dry conditions which will eliminate 

 this loss. Under these conditions it is probably best to use the 1-50-5000 formula 

 and increase the amount of seed enough to offset the formaldehyde injury. 



Station Farm Experiment, 1923 



This was the same field on which the experiment of 1919 was located. It con- 

 sisted of 40 rows, 12 inches apart and 75 feet long, seeded on April 26 at rate of six 

 pounds per acre. The soil was very dry and remained so for 48 hours after planting. 



19 



