NATURAL ENEMY AT WORK.

Shannon News, 22 June 1923, Page 4

NATURAL ENEMY AT WORK.

GOOD RESULTS IN NELSON -• ORCHARDS. The appended letters from Nelson brehardists show conclusively that aphelinus mail, introduced by the CawthfOttiv* Institute to combat woolly aphis, is doing valuable work. Mr. H. E. Stephens, of Stoke, writes! “I was much interested in your account of the success of the aphelinus' <Imali sent by the Oawthroh Institute to Auckland last year t o combat woolly aphis, but have seen no mention of - similar results here. Last DecemberI was supplied by Mr. Philpott with a number of these parasites which I liberated on a Munro tree that ' was x"well infected • with aphis. - Unfortm*’ 1 nately a heavy thunderstorm occurred within an hour of their liberation, and ■■ > as the wire-netting round the tree, was not covered with scrim, I thought I had* lost the lot. I watched the tree carefully for months without seeing any result until just recently, when on examining the tree I found that some of the twigs v r ere covered with the black skeletons of woolly aphis, each "with a < hole in it, showing that the aphelinus; was at work. I also found adult apheliuus on the tree. I am hopeful that ' next spring will see such ,an increase in’; these parasites that woolly aphis will * soon be a thing of the past in Nelson. • orchards; and as a fruitgrower I wish.--, to voice our appreciation of the good/' work that is being done for us by Dt. Tillyard and the Cawthron Institute.” Mr. H. Pickup,*Stoke, writes: -. “A little over a year ago, Drr Tillyard askf-;> ed me to select the apple tree most affected with woolly aphis and surround - it with 1-inch mesh wire netting*'-to keep out birds. I happened to havO ar n tree that had been knocked about a kit 5 * (a Munro), and it was white with the,, blight. This' l l netted in as instructed-*/ and Mr. Philpott came along and-liberie ‘ ated about 80 aphelinus mali. Shortly ' after Mr. Philpott came again and saw that numerous aphis were parisittsedf® I was asked not to spray the tree and

did not do so during the following winter and spring, nevertheless the woolly j aphis gradually died out and all through -v I this summer the tree has been, and is j now, quite clean and free from blight.' j Again early this season, I received a i large consignment of aphelinus mali ' Dr. Tilly ard and liberated them on other;/ badly infested Rokewoodtrees. I soon ;• ; saw they had got right down to busii ness on the woolly aphis, and, I feel . | confident, the effect will be as good as-i- ---‘ in the first experiment. ” ! Mr. R. H. Simpson, of Stewart Block; near Redwood's Valley, writes:—“ln . January last we received from the Cawl thron Institute a number of tubes'-of ! aphelinus, and liberated the insects on ' i different trees in the orchard affected by. 1 woolly aphis. On recent examination rof the trees, the work of tkes little in- -■ ■ sects is plainly discernible in all parts ,of the orchard. On the trees on which - the aphelinus were liberated, thousands /> of dead aphis ’shells are to be seen, and bunches of woolly aphis hare been clenaed right up. On warm days great - -numbers of the little insects can. be seen crawling up the branches. Thetrees have been sprayed twice with lime sulphur and arsenate of lead- since - the • insects ivere placed,on them, but it ap-.v l parently has done them no hann. If this little ins’eet once gets properly es- ( tablished in the orchards, the i tion of the woolly aphis pest is cer-

| tain." i Mr L. Mackay, of the Moutere, has I informed Dr. Tillyard that he has found ' the aphelinus doing good work, and • 1 that it is spreading in his orchard.