674 THE FARMERS'* HANDBOOK. 



Cabbage Aphis. 



This insect (A]>his brassicce, Linn.) is one of the worst with which the 

 growers have to contend. It breeds very quickly, and lives on the juices of 

 the plant, giving most trouble in a dry season when the plants are stunted 

 and not growing. 



The young, when first hatched, are yellow ; in the second, wingless, stage, 

 a dull olive-green, covered with a mealy bloom ; when full-grown, of a greyish- 

 green tint, with the eyes, legs, spots on either side of the body and tips of the- 

 antenme black ; the winged forms are of a much lighter green colour. 



Controls. — Spraying with tobacco and soap wash early in the season, when 

 the plants show the first signs of its attack, is recommended ; also dusting 

 with soot or lime early in the season. 



Spray with kerosene emulsion, made on the following formula: — Hard 

 soap, ^ lb., kerosene 2 gallons, boiling water 1 gallon. Dilute or dissolve in 

 22 gallons of water. To make, dissolve J lb. of hard soap in 1 gallon of 

 boiling water ; then remove the vessel from the neighbourhood of the fire, 

 add the kerosene and churn for ten minutes. One essential condition of 

 success in making this emulsion is that the liquids should be as warm as. 

 possible. It is also necessary that the water be as soft as possible. 



In preparing this compound, the main trouble is in getting a true emulsion. 

 which can only be done by thorough agitation. This is best done by pump- 

 ing the mixture into itself for some minutes. When this creamy mixture 

 becomes cold, it gets thick and almost solid, and there should be no trace of 

 free oil on the surface. If there is still unemulsified oil, the best plan is to 

 add some more boiling soap solution and pump again. Free oil destroys the- 

 foliage. Care should be taken to use the best kerosene and good soap. 



Kerosene being highly inflammable, particular attention should be paid to 

 the directions for mixing well away from the fire. Boil the soap and water in 

 one vessel and carry it away from the fire before mixing with the kerosene. 

 Any kind of vessel may be used. 



Kerosene attacks india-rubber ; consequently the tubing, and indeed the- 

 whole spraying outfit, must be well washed with hot water directly after use. 



Sometimes it is of advantage to prepare a quantity of emulsion as a stock, 

 for use as required. When this is done and it is required to dilute it to make- 

 up a spray, this should be done by adding boiling water to it, and not by- 

 melting it over the fire, which is dangerous, especially indoors. 



Cutworms, Eel-worms, and Rutherglen Bug. 



Cabbages and cauliflowers are also attacked by the above-named insect 

 pests. 



Suggestions for the control of cutworms will be found in connection with 

 maize (see page 437), while eelworms and Rutherglen bug are dealt with in 

 connection with potatoes (pages 492 and 491). The change of crops advised in 

 connection with these pests will, of course, be adapted by the grower to his- 

 own conditions. Those mentioned in reference to eelworms, for instance,, 

 are not likely to suit the grower of cabbages, but the principle still applies, 

 viz , change to some crop that the eelworm will not attack, or, in other 

 words, deprive them of their natural food and starve them out. 



