STOKE FRUITGROWERS' ASSOCIATION.

Nelson Evening Mail, Volume LII, Issue 165, 10 July 1918, Page 6

STOKE FRUITGROWERS' ASSOCIATION.

SPRAYING EXPERIMENTS.

•REPORT BY GOVERNMENT INSTRUCTOR.

(Concluded.)

At the meeting of the Stoke Fruitgrowers' Association- on Friday evening Mr W. C. Hyde, Government Orchard Instructor, presented a report on orchard spraying experiments in the season 1917-18, as follows: Naphthalene Lime Sulphur.—This new spray was put on the market this season for the first time, and claims to be a combined fungicide and insecticide. It was tested on a block of apple trees — Rokewood and Rome Beauty—in the orchard of Mr Scott. The first application was made on September 24th, at a strength of 1-10: the Rokewoods were just breaking their buds and the Rome Beauties were dormant. On October 10th, when the blossoms commenced to open, naphthalene lime sulphur was applied at a strength of 1-50. A further application was given when the petals had fallen—November 9th—at a strength of 1-100. This was repeated on December sth, when arsenate of lead was added to; the mixture. The further spraying of this block consisted of arsenate of lead^orily. Tiro Rokewoods in this block at the

beginning of the season were—as is so common with that.variety—affected with woolly aphis rather badly; old established colonies had caused considerable disfigurement. When inspected on December sth very little aphis was showing, and the foliage and fruit looked particularly well. In April, when the fruit was picked, the trees compared well with trees sprayed with lime-sul-phur, the fruit being clean and bright, and the general condition of the tree good, the infection of woolly aphis being considerably reduced. In the above applications well water was used, and arsenate of lead used in combination without, at any time, the least sign of burning being experienced. The addition of naphthalene seems to thicken the spray and give greater adhesion. Further tests with this mixture will be of great interest. The price per gallon is ' the same as ordinary commercial limesulphur. ' -. Orchard Sanitation.—The stress laid on this subject, by scientific writers and some local growers, during recent years is no doubt timely. Abundant and thorough cultivation in the orchard is a very fine thing, but as the above writers have pointed out such cultivation ia infinitely more effective if it is done with discrimination and consideration given to its relation to orchard insects and fungi. The experiment under this heading was carried out in the orchard of Mr "Tightband, of Brightwater. Unfortunately, the results have been heavily discounted by the fact that owing to its situation, close observation of the experiment throughout the season has not been maintained. The time taken up by these experiments is very considerable, and it is to be hoped an -organisation, with more time and money for the purpose, will very soon come to our assistance.iu this work, which is of such general benefit to the fruitgrowing industry, in Nelson. The experiment was carried out on a large block of Sturmer apple trees in Mr Lightband s orchard. During the previous season no spraying had been done, as the -trees, were unsatisfactory, and it was decided to pull them out", the position being a bad one for black spot fungus. When dormant the trees received a good dressing of lime-sulphur—winter strength, and before the "winter" or "resting ' spores from the fungus infected fohage became active, the section was carefully ploughed.' (This experiment does not consist of a treatment that is new, except that cultivtion all through the season was considered from the point of view of counteracting fungus infectioiias well as the vigour of the trees). The ploughing was done before the buds started in spring and was "off" the trees, the plough being set to reduce the strips between the trees as much as possible—in fact, it was reduced to a diamond shaped piece of ground round each trunk; this, too, was afterwards turned right over, and the land harrowed. 3Sp further cultivation was done for about two months, when the land was thoroughly disced and harrowed. The only spraying throughout the growing season consisted of arsenate of lead. The crop when inspected after it,had been picked looked well, the skin of the fruit being very clear. A careful count was made, and it was found 40 per cent, of the number of apples-JTad been infected with black spot fungus. The count is large. but a very great number of those counted out were infected only to the ex tent of a spot about &-inch in diameter ; in fact, the majority were apples of that description. The previous season .- crop was very badly infected. It should be noted here that the ex n-n-iment was carried out as above —with out summer spraying—merely to test the effeet of such a system of cultivation. Not a single advocate of.the.sys--e:a suggests that summer spraying should be.dispensed with all together Brown Rot of Peaches: Is Lime-Sul-phuFSummer Spraying Safe and Effeo ti ce ?—As reported a few months agewhen dealing with this fungus, Mi Scott sprayed two rows of Muir in his orchard with lime-sulphur 1-150 one month after the fruit had set. A number of trees of the same variety were left unsprayed on this occasion as a check. About a month before picking ;= number of these peach trees received a. second summer spraying of lime-sulphui «t a strength of 1-120. At the time of nicking there was a marked improvement in the crop from these trees, which had ' received the double summer spray. Tree? m hich rcrt-i\ed one summer spray, and those which had none during summer, .4iow little difference between each other as far as crop infection is concerned. The infection on this block of peaches, a variety very susceptible to brown rot, was generally low, a condition no'doubt due to the regular double spring spraying they have received in the past. Owing to the prevalence of brown rot during the first few weeks of this year, a grower made enquiry regarding treatment for a crop of Salway peaches—which are very-subject to the disease—then maturing. It was decided to apply atomic sulphur to one-half the number of trees, and lime-sulphur (commercial) to the other —a few trees being 4eft unsprayed as a check. This .was done on February 21st, when the weather was bright and hot. Atomic sulphur,' 151bs to the 100 gallons of water was applied to the trees on one section, and' lime-sulphur, 1 gallon to 125 gallons of water.was applied to the tree? on the other. No spray injury of any kind was observed..- The crop was pick - satisfactorily. A sample of fruit war coloured but quite firm, and marketec, satisfatcorily. * A sample of fruit was put into store from each plot and ex amined on March 16th, when it was •found the peaches which had receiven the atomic sulphur summer sprayhn-a a' 40 per cent, infection of brown rotThose which had received the lime-sul-phur summer spray had a 12 per cent. " infection'. And—very, unexpeotedlv—--the sample of fruit from trees which received no summer spray were quite clean-on the date of inspection. Ar.. other set of samples which when-uiok-'pd had heen treated with borax solution ;4 ozs.. to the gallon of water gave tb<name result.

Enquiring into the history of the check trees which gave such unexpected results, it was found they had beei. sprayed with bordeaux 8-6-40 as the bud? were breaking. Later, having a quantity of bordeaux (3-4-40) to spare .and slight leaf curl showing on a few Salway trees at. the ends of the rows, it was applied to these trees, when the fruit was a bom the size of small walnuts. About 10 per cent, of the foliage dropped as a result of this application—probably foliage infeeted with leaf curl. The trees recovered quickly and finished well. The winter treatment for the majority of the trees, including those summer sprayed atomic sulphur or lime-sulphur, was lime-sulphur 1 gallon to 10 gallons of water, applied when the buds were beginning to swell. At the time of inspection the Salway trees sprayed with bordeaux at the end of winter (1917) were looking much the best, the foliage Being larger, better coloured and with little or no "rust."

SUMMARY OF RESULTS. 1. Lime-sulphur has again demonstrated its. superiority over atomic sulphur as a general summer fungicide in the orchard.

2. The invigorating effect of spring applications of bordeaux to Dougherty apple trees is confirmed. 3. On <Sturmer apple trees in a locality favourable to "black spot," t-or-deaux spraying, followed by applications of lime-sulphur, gave better results . n\n a full series of lime-sulphur spriying only—arid without russeting the fruit. 4. Weak solutions of bluestone as ?t summer spray for apple trees proved impracticable. 5. Fungus spray, immediately followed by oil in spring on Sturmer apple trees" did not give encouraging results from the point of view of economy. 6. Naphthalene lime tlulphur gave very promising results as a oommai-'-ial fungicide and contact insecticide. 7. The proper timing of orchard cultivation has an important bearing on the fungus infection of orchard trees. 8. Regarding the summer spraying of peaches for brown rot fungus, the experiments carried out proved that limesulphur 1-125 and atomic sulphur 151bs to 100 gallons of water can be applied to peach trees in summer without burning them. They also indicated that j summer sprays of lime-sulphur are a better preventive of brown rot fungus than atomic sulphur so applied. Also, that bordeaux is a more effective spring spray for peaches than lime-sulphur. : DISCUSSION ON THE REPORT. During the discussion which followed this extremely interesting' and valuable report, Mr A. Gilbert referred to ! a very lengthy discussion on brown rot, which took" place at the Auckland conference. He said more good information was to be obtained in their own meeting there in Stoke than in the bigger meeting at Conference. -'•A very hearty vote of'thanks was accorded Mr Hyde for his interesting report and for the valuable time he has. put into work for the Association. This was carried by acclamation. In replying, Mr Hyde wished to than - those of* the Spray Experiment Committee with whom he had worked, itnd said the-sooner the Cawthron Institute o-ets into being and into working order the better. "We must have an experiment station," concluded Mr Hyde. It was resolved to again forward the resolution with regard to the establishment of a horticultural station in the Nelson district to the -Government Agricultural Department.