New York Agricultural Experiment Station. 929 



At the Station four careful tests with these 



lests oi pads were made during 1912 and two during 



tar-pads. ? 



191.3, and the. results justify a hearty recom- 

 mendation of this method of preventing injury to early cabbage 

 by maggots. In three of the tests injury from maggots was great 

 and benefit from use of the pads was marked. In the first 

 field 400 disks were applied to four alternate rows of plants on 

 May 22, and during the next month ten per ct. of the check 

 plants were either killed or badly wilted, as compared with one 

 per ct. of those protected by the tar-pads. In addition to this 

 notable numerical difference, the cabbages in the protected rows 

 were slightly larger than those in the check rows. That is, mag- 

 gots had worked on the unprotected plants and checked their 

 growth even where the attack was not severe enough to result in 

 death or distinct dwarfing. This same effect was observed in all 

 the other tests where maggots were abundant. This check to 

 growth materially interferes with early heading, a most important 

 factor in profitable marketing of early cabbage. In the second 

 test 16 per ct. of the check plants were killed or seriously in- 

 jured, as compared with 5*/2 per ct. of those protected. In this 

 case the lumpy condition of the .clay soil and low setting of the 

 plants made it impossible to place the disks so that effective pro- 

 tection could be secured in all cases, and a heavy shower soon 

 after placing the disks covered many of them with earth and 

 allowed the flies to deposit eggs on the stems above the pads. 



In the third test of 1912, the injuries on checks and protected 

 rows were eight per ct. and two-thirds of one per ct. respectively. 

 In the most striking test in 1913 disks were placed on about 700 

 plants in six alternate rows, on May 3. By June 5 the alternate 

 rows showed marked differences, as brought out in the illustra- 

 tions. It was estimated on June 9 that 93 per ct. of the pro- 

 tected plants and only 45 per ct. of the checks would make market- 

 able heads. 



After harvest it was found that nearly three-fourths of the 

 plants in the protected rows had furnished suitable heads for early 

 marketing and only one-fifth of those on the check rows. 

 59 



