ON PESTS GENERALLY. Io8l 



have to be considered by the gardener if he wishes to enjoy the 

 confidence of his employer. 



So far we have assumed that the pests have been confined 

 to outdoor crops; but there are also indoor ones to be thought 

 of, like greenhouse and stove plants, fruits under glass, &c. 

 These, however, have been treated under the respective chapters. 



For poisoning the food-plants in order to circumvent chewing 

 insects like the larva of Moths, Butterflies, and Sawfiies, the 

 grubs of Beetles which feed exposed, as well as the Beetles them- 

 selves that lay the green parts of plants under contribution, 

 Paris Green is best used in the proportion of ioz. to 2ogal. of 

 water. Many growers also add ioz. of lime to the above, as the 

 last-named minimises the chances of the foliage being injured. 

 The mixture should be kept stirred or the Paris Green will 

 settle, and it should be distributed in a nice fine spray. With 

 fruit-trees on no account should the preparation be employed 

 when they are in blossom. So far as the fruit itself is con- 

 cerned there is not the slightest danger to the consumer if the 

 arsenite is used in the proportion stated. Manufacturing agri- 

 cultural chemists, like Mackey and Mackey, Bermondsey, keep 

 Paris Green Paste ready for making the insecticide ; and this is 

 preferable to having to mix the powder one's self. Hellebore 

 (in powder) dusted or blown on to the trees in the early morning 

 is also a capital insecticide, especially in the case of the Sawfly 

 and Caterpillar grubs on Gooseberries.- Although a strong poison, 

 hellebore is soon rendered harmless by contact with the outside 

 air, and must therefore be renewed. 



For sucking animals, one of the best all-round preparations is 

 kerosene emulsion. If properly made the kerosene does not 

 separate and cause injury to the plants. It may be procured in 

 this country of Messrs. Mackey and Mackey, in a concentrated 

 form, and all that the user has to do is to dilute it to the proper 

 proportions, which will vary somewhat with the kind of tree 

 under treatment and the age of the leaves. The younger the 

 foliage, the weaker the solution. The exact proportion may be 

 determined by the gardener himself. These emulsions are best 

 bought from firms with the machinery for making them. 



A very good home-made preparation for similar insects consists 

 of ordinary petroleum i wineglassful, and hot water 3gals. The 

 difficulty about this solution is that the petroleum does not readily 

 amalgamate, and constant stirring is necessary. It is a very 

 good plan to put sufficient soft soap in the water to discolour it, 

 as this has been found preferable to plain water. The soluble 

 petroleum is preferable to the ordinary kind. 



Again, it cannot be too widely known that hot water is a most 

 useful insecticide, and we have found it especially so for Scale, 

 applied at a temperature of isodeg. It has the merit, too, of 

 being harmless to the plants under treatment — neither leaves, 



