xxxviii PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



Scientific Committee, May 19, 1903. 

 Dr. M. T. Masters, F.R.S., in the Chair, and eleven members present. 



Codl'ui Moth in California. — Mr. Fairhurst, Mitcham, described how 

 the orchards in California, amongst the foothills near to Monterey, about 

 seven miles from the sea coast, have of late years suffered much from the 

 caterpillars of the codlin moth ; and each year the plague is becoming 

 worse, in spite of repeated sprayings from the blossoming time up to near 

 the period of ripening. He adds that the bulk of last year's crop of 

 Apples was so bad as to be almost unsaleable. Mr. Saunders reported : — 

 " The codlin moth (Carpooapsa pomonella) makes its appearance about 

 the end of May. The females lay their eggs on or close to the ' eye ' of 

 the Apples. Only one egg is laid on each fruit. The young caterpillar is 

 hatched out in about a week or ten days, and at once eats its way into 

 the Apple, working its way down the core to the pips, which it feeds 

 on. In about three weeks or a month it is full-grown, and then gnaws 

 its way to the surface of the fruit, and unless (which is frequently the 

 case) the Apple has already fallen lets itself down by a silken thread to 

 the ground ; or, if the Apple is already on the ground, it merely crawls 

 out. In either case it at once endeavours to make its way to the nearest 

 tree, fence, or post, and, crawling up a short distance, finds some crack 

 or other sheltered position, in which it hides and spins a silken web round 

 itself, covered with a sticky substance. Within this shelter it remains 

 during the winter, and early in the spring becomes a chrysalis, from 

 which the moth emerges in May. It is obvious that when once the 

 caterpillar is within the fruit nothing can be done to kill it without 

 destroying the fruit ; but if the tree is duly sprayed before this event 

 takes place, and after the eggs are laid, the crop will to a great extent be 

 saved. The proper time to spray is immediately the blossoms have 

 fallen, and the best insecticides to use are either 1 lb. of Paris green, 

 kept well mixed in 200 gallons of water, to which should be added an 

 equal amount of lime to that of Paris green (bulk for bulk), to prevent 

 any injury to the foliage ; or a solution of paraffin emulsion may be used 

 with almost equal success. When any Apples fall, they should be picked 

 up at once ; and any that are found to contain these caterpillars destroyed. 

 All rubbish, stones, and other things under which the caterpillars could 

 shelter should be removed, as they sometimes have to make shift with 

 such. A number of the caterpillars may be caught by tying hay-bands 

 round the stems of the trees, about 1 foot from the ground and another 

 about 8 feet ; or folded strips of old sacking, canvas, or some other similar 

 material should be wired or tied round the trees, the object of this being to 

 afford the caterpillars a convenient resting place in which to undergo their 

 transformations. These traps should be examined every now and then,, 

 and any insects found in them destroyed. The bands should be put into 

 position by the end of May. Before the buds in the spring show any 

 Bigns of opening, it would be well to spray the trees with a caustic alkaline 

 wash, composed of 1 11>. of caustic soda dissolved in half a bucket of 

 water, then add '[ lb. of pearlash ; stir until dissolved, add enough water 



