Appendix. 515 



Fruit trees should not be sprayed with these arseaical washes when 

 in flower, as the bees are so readily poisoned, and they should not be 

 sprayed for at least four weeks before the fruit is gathered. This is a 

 point we must remember when gooseberries and currants are growing 

 beneath apple«-and -plum. 



These arsenical washes should be put on in as fine a spray as 

 possible. 



Animals may be kept in the grass orchards when the trees are sprayed, 

 as long as they cannot get at the actual wash. 



All receptacles in which the arsenical wash has been mixed should be 

 cleaned and kept away from stock. 



We must remember that these washes, especially when concentrated, 

 are deadly poisons. 



Arsenate of lead is generally used in conjunction with Bordeaux 

 mixture, and it also emulsifies paraffin, so that we can combine a 

 fungicide and an insecticide for mandibulate and haustellate insects 



PAEAFFIN EMULSIONS OR CONTACT WASHES FOR 

 HAUSTELLATE INSECTS. 



PARAFFIN EMULSIONS. 



For winter application these washes may be used very strong, but for 

 summer use they must be much diluted. 



Except in bad attacks of scale insects they cannot be recommended for 

 summer use, nor paraffin in any form. 



In spring it may be used for red spider on gooseberries in the form 

 given under Paraffin Jelly, but it is best to apply it before the leaves are 

 showing, as even the finest oils do harm to vegetation. 



Through the work of Mr. Spencer Pickering we now know more of 

 these matters, and growers will do well to use the oil recommended by 

 him, known as Solar Distillate. 



The usual form of paraffin emulsion is soap emulsion, but Mr. Pickering 

 has recently shown that metal emulsions are superior as emulsions. Pro- 

 bably for scale insects the metal emulsions will soon supersede the soap 

 emulsions, but for aphides they are not likely to do so, as the soap is an 

 active killing agent, holding on to the mealy skin and is alone sufficient to 

 destroy them. 



A. ' Soap Emulsions. 



The Klley-Hubbard formula is also given here, but the emulsions I have 

 used have been the following : — 



2 L 2 



