LEAFLETS FOE GARDENERS AND FRUITGROWERS.

Otago Witness, Issue 2310, 9 June 1898, Page 8

LEAFLETS FOE GARDENERS AND FRUITGROWERS.

No. 27. — Cinebaeia Fly (Phytomyza nigricomis.) By T. W. Kitik, F.L.S., &c, Lond., Government Biologist. In 1894- I sugested tho use of tar water for this troublesome pest, which damages so manygarden and greenhouse plants, " pointing out that " tar is obnoxious to all insects and they will* get away from it if possible." The way to prepare the tar water is -JLlb coal tar boiled in one' gallon, of water, and when 'boiled for some time diluted with 50 gallons of fresh cold water. The following extracts from letters of

a com spondent, a practical gardener well known to all horticulturists in Wellington', will show the efficacy of the remedy advocated: — " The Grange, Wadestown. October 31, 1896.

" I would like to tell you my experience with your tar remedy for leaf-miner on. cinerarias. I grow a good batch of them here, and last year I followed your directions for using tar as a preventive of the miners' depredations. I sprayed perhaps about half a dozen times,' and during the whole growing season I was unable to find a miner on tlie planLs. Tlii3 year I tried the difference. I have trusted to hunting them, with the result that many of my plants were quite spoiled, and every one more or less disfigured. The hunting business not only required more time than I could afford, but even when found the insects had already done more or less harm, so in future I will pin ray faith, on your tar. — Faithfully youra, " W. H. Taylob." " Wadestown, September 9, 1897.

" Some time ago we had a talk re cineraria miner. I told you then that I had tried your tar remedy with satisfactory results. I now report to you result of further trial, and will review my past experience. I used the remedy first in 1895, and had not a single leaf injured until the plants were in full flower, when, owing to the plants being surrounded by other flowering plants, I was unable to use the tar water ; then I had plenty^ of the miner. Some of my gardening acquaintances were sceptical as to the efficacy of. the remedy, suggesting that I would have been free from the pesfc in any case. I couldi only .say that plenty of the inseebs could be found on the thistles all over our place, and could therefore see no reason why I should 'enjoy immunity more than the others. Last season, with a view to testing the question, I made no use of the tar water, and before this time was picking off the riddled leaves. This season I have used it again, and up to this date have not seen a single solitary miner on my plants, about 80 in number, though at least two growers have to my knowledge had their plants quite ruined by them, and I saw it on one man's plants about three months ago. When I use the tar water I syringe the glass, staging and floor of the house mainly, giving the plants a light dose. Ido not see how an experiment could be more complete than mine has been, and I am quite satisfied — Yours faithfully,

" W. H. Taylor."

When writing the article referred to { in. 189*) I mentioned that in Europe a small Ichneumon fly helps to keep tho miner in check, but that it had not boon seen hsre yet. Last year Captain Broun reported its discovery in Auckland, and soon after I bred specimens here, but in this district it does not make any appreciable difference.