64 TREATMENT FOR ROOT-FEEDING SPECIES. 



There is also another subterranean species (Dacty- 

 lopius radicum, Newstead), which has been known to 

 cause serious injury to the strawberry when cultivated 

 in pots. In this instance, however, there could be no 

 doubt that the insects were introduced in the fresh 

 turf used in the cultivation of the plants. Externally 

 this species very closely resembles the preceding, but 

 is a trifle larger. In both species the white woolly 

 retreats and ovisacs secreted among the roots of the 

 food-plant bear a striking resemblance to the fine 

 white mycelium commonly met with on grass roots in 

 loamy soils, and, owing to the striking similarity, it is 

 feared the insects get overlooked and passed off :is 

 " fungus spawn." 



Treatment. (1) Never, if possible, use the outside 

 of turf -stacks or fresh turf for potting purpose-. 



(2) Do not turn the infested plants out of the pots 

 while in the conservatory, as a strong current of air 

 may sometimes carry away a patch of the woolly mute- 

 rial, and with it the eggs or females. 



(3) Infested plants should, at the proper season, 

 have all soil removed from the roots and thoroughly 

 washed in two lots of clean water. The pots from tin* 

 infested plants should be immersed in scalding \\nter 

 or heated to destroy any adhering eggs of insect-. 



(4) To destroys the Coccids on growing plants re- 

 move the pot and thoroughly spray the exposed roots 

 and soil with carbon bisulphide (CS 2 ) using a small 

 glass spraying apparatus. Scald the pot and have it 

 in readiness for replacing immediately after spraying. 

 The eggs, unfortunately, are not destroyed by this 

 process, and it will be found necessary to repeat the 

 application. I have not found the carbon bisulphide 

 injurious to maidenhair ferns while in active growth, 

 providing always that the plants were kept in the 

 shade for a week after spraying. 



