1897.] CADDIS WORMS 153 



tell you about the Caddis worm attack on water-cresses ? 

 So much harm was being done that the unlucky grower 

 was in much trouble, and on running the matter up it 

 appeared that formerly there were numbers of trout in the 

 water, but lately the landlord's wife had a fancy to encou- 

 rage herons, and so came the curious sequence. The 

 herons cleared off the insect-loving trout, so the vegetable- 

 eating insects got ahead, and the watercress grower could 

 not pay the rent of his half acre of cresses. I suggested that 

 as the herons were encouraged by the lady, perhaps she, if 

 applied to, might to some degree make good the damages !"] 



March 5, 1897. 



DEAR MR. WISE, You asked my views about moles 

 at Strawberry roots. I should say it would be quite worth 

 while to spare them as you are doing, and see what comes 

 of it. If they take the Otiorhynchus grub (of Orchard and 

 Hop weevils) this would meet a difficulty which we hardly 

 know how to fight at present, and if the moles took these 

 grubs one might hope that they would take other under- 

 ground kinds, which are kitchen garden pests, almost uncon- 

 querable by other remedial means. I should doubt, however, 

 whether they would be of much service against Winter 

 moth chrysalides (fig. 30). Very likely I am not right, but 

 the mole seems to me to prefer more open ground and a 

 larger scope of operations. 



April 8, 1897. 



So far as I know the only treatment for Black Currant 

 Gall mite, Phytoptus ribis (fig. 65), which has been in a 

 measure successful, is that reported by Mr. ]. Biggs, of 

 Laxton, East Yorkshire, in my seventeenth Annual Report, 

 p. 93. There, if you will turn to it, you will see we have 

 treatment to clear the pest from all localities, whether 

 straying on the twigs or on the ground ; or in the buds, 

 this by breaking them off. Mr. Biggs observed, writing 

 on the 2oth of April, 1892: "You will, I am sure, be 

 interested in knowing that I have, to a certain extent, 

 prevented the Phytoptus utterly ruining my black currant 

 trees. As you suggested in a letter of last March, we 

 syringed the bushes twice with the solution of Paris-green, 

 which I procured from Messrs. Blundell, and gave the soil 

 all under the bushes a good coating of caustic lime ; I also 

 gave the bushes another dressing of the Paris-green. Just 

 when the buds appeared this spring I had a boy gathering 

 all the little knobs off the trees. The result has proved as 

 satisfactory as I could expect, considering the condition of 



