282 INSECTS 



water to do it properly and afterward diluting to spray- 

 ing strength. It usually requires about one hour's 

 boiling to get the proper combination and, when re- 

 duced with warm water and applied fresh on peach 

 and plum trees, there is no more effective remedy 

 against the pernicious or San Jos^ scale. The material 

 is, of course, quite as effective a killing agent on other 

 trees as well; but on pear and apple it is more difficult 

 to reach all the specimens in their hiding places behind 

 or under bud or bark scales, in crevices or, in the case 

 of apples, among the hairy clothing of the terminal 

 shoots. On such trees the wash should be applied with 

 great force and as thin as possible so as to aid its pene- 

 tration. On peach, plum and apricot trees it exercises 

 also a beneficial effect in checking certain fungus dis- 

 eases and improving the general health of the tree. 

 On trees in foliage this wash should never be used, nor 

 on conifers of any kind. As to the practical work of 

 making the wash, place the lime and the sulphur in an 

 iron kettle over a brisk fire, pour in hot water enough 

 to cover and start slacking, which will bring the mass to 

 the boiling point at once. Add hot water slowly, stir- 

 ring to prevent burning and to facilitate the combination 

 of lime and sulphur. One part of good lime is a little 

 more than enough to combine one part equal in weight 

 of sulphur and any excess of lime remains as white- 

 wash and adds nothing to the effectiveness of the 

 material. If the lime is poor, a little more should be 

 used to make sure that all the sulphur is combined. 

 If flowers of sulphur are used, three-quarters of an 

 hour's boiling is sufficient if hot water is used as a 

 starter. Otherwise an hour is better. If ground sul- 

 phur is used boil half an hour longer. 



Where large quantities of the wash are to be made 

 up, live steam is quite generally used, and the mixture 



