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immediately eats its way into the soft covering of 

 the roots and the underground portion of the stem, 

 in a short time completely destroying the plant. 

 The presence of the maggot is usually indicated by 

 a wilting of the affected plants during the heat of 

 the day, with nightly recovery for a time. The 

 plant is eventually killed outright or its growth 

 checked to such an extent that it fails to properly 

 mature. 



In the southern cabbage-growing sections the 

 harlequin cabbage bug is frequently a serious pest, 

 especially on the late crop. This insect is a suck- 

 ing insect, requiring contact poisons for its control, 

 but unfortunately many of the common contact 

 poisons used in sufficient strength to destroy the 

 insect seriously damage the cabbage. The only 

 effective method of treating this pest is to plant a 

 trap crop, usually mustard, which is planted early 

 enough to develop before the cabbage. Both crops 

 and insects are then destroyed by spraying with 

 rather strong kerosene emulsion. 



The club root is the most widespread, and perhaps 

 most serious disease affecting the cabbage. The 

 trouble is caused by slime molds attacking the roots 

 causing them to become distorted and greatly en- 

 larged. Eventually they become unable to supply 

 the plant with the necessary moisture and plant 

 food. The plant becomes dwarfed and light green 

 in color. It wilts quickly in warm, sunny weather, 

 but for a time recovers at night. The plants some- 

 times mature their heads, although they are usually 

 small. The most effective remedy is crop rotation. 

 The spores of the disease are extremely resistant 

 and retain their vitality for a number of years. The 

 soils in the seed beds should be thoroughly steri- 



