FRUIT INDUSTRY

Nelson Evening Mail, Volume L, Issue 175, 4 October 1917, Page 2

FRUIT INDUSTRY

SPRa.'S ANl> SPRAYING. AX INSTRUCTIVE PAPER. (Paper on Sprays and Spraying bv Mr Thus. C. C. Scott.' Stoke orchardjst, read before the Stoke Fruitgrowers' Association, Fridav, 28th September, .1917.) No. 2.

BLACK SPOT. ' The spr.-ys in use for checking this ! disease are iime sulphur solution, atomic ! sulphur, ii ;i sulphide, Bordeaux, and j under experiment naphthalene, lime sulphur and Bordeaux-oil. ! This last was referred to in my in- i troductory remarks, and is being "tried. | by several Stoke orchardists. It con- 1 sists of .spraying at the delayed dor- j mant stage or' even later a Bordeaux ! of winter strength followed immediately it dries on the tree by emulsifying Margoylo prepared red spraying oil," diluting to 1-50 or 1-60, and" applying it j thoroughly. According to the " condition of the tree a dilution of oil as strong as 1-20 has been applied wit (rout detriment to the tree. This experiment has been very successful in Australia lor a number of years. Xo further spraying of fungicides was applied, and clean crops have been claimed as a result. It would .be interesting to try lime sulphur solution in the same way as above, say. a strong solution at the delayed dormant stage, 1-10 <«r 1-20 followed immediately by oil. No further sprayings to be given except, of course, arsenate of lead for Codlin moth and i leaf roller. j lor a li.-i'u time diordeaux was the j standard" spray for Black Spot, but- j russetting was aimost inevitable, and ' .sometimes the russetting was worse , tha.n the disease. Just recently lime sulphur has come into use. and has al- | ready given better results and no rus- i setting. • To spray thoroughly one i eeds to ' know something of the disease one i wishes to com Cat. S. W. Foster, of • the General Chemical Co. of San Fran- ' cisco. referring to Black iSpot, says : | "Loss of crop from early spot iufecLion j lias sometimes 'jee.n vrongly attributed j to lack of poliii:-tion. . . . The j spot fungus thrives best in cool, moist j •weather, such as is most likely to n<- ' cur in the spring-time. . The period of greatest infection is about the time the first leaves appear before the blossoms open, until three or four weeks after Glooming period. Hot weather is unfavourable to the fungus, but late infectious ;n;>y occur in February or —arch." This lias been our experience in Stoke in the past, and it mav occur again. j ■Mr Leroy "Guilds, of Hood River Ex- ,' periment Station, s;<vs that no more ! satisfactory recommendation can be. given for the control of Black Spot than five applications of lime sulphur, dilutions being reduced as the season ad- . vances. "Lime sulphur readily lends ] itself to the combination of other in- j gredieu.ts to control Black Spot, j powdery mildew. Codlin moth :uu\ \ aphis. ... In the past control I measincs ]'<-v mildew and- sunt have not ' been attempted early enough to brim: j about i-.-t-rrlv effective results."

Lerc.y C'iilcls goes on to pav they arc still experimenting in Kood River.

They ;\re inw dusting the trees instead of spraying for spot and niotli. They .-'.re considering greater dilutions of !in?e srlphnr than at mrsent used.

The are considering substitutes for lime sulphur fo prevent burning when

J spraying in summer 4'or Black Spot. j They are studying the life history of i the spot disease, and much valuable ' data has been obtained. With regard to the summer burning, | my own experience goes to show that with a proper; dilution of lime sulphur, even if combined with arsenate of lead, . one need fear no burning. I have ; spra) ea on the hottest day last sum- ' mer lime sulphur 1 in 120 without detri- ' nient. ; In order to cdipare results with a 1 practical grower in Hood River, I cor- ,' responded with Mr E. 'H. Shepard, edij tor of Better Fruit, and asked him the ! following questions, to which he courj.tcously replied. The questions and answers are here given : ! (1) Are t'ie percentages of clean fruit i in Hooch River orchards high when lime I sulphur is used? , Answer: The percentage of clean j fruit is high in this valley where lime . sulphur is used for fungus. (I) Do the growers use a pressure of 2Colbs consistently? .Answer: We use a pressure of 200 j to 2501b5. j (O) I>o 'they put the first spray on j the delayed dormant or green tip to j control spot and then follow it with another on the pink blossom?

Answer : We use 1 im.*.-? sulphur in delayed dormant, for scab : also in the pink, calyx and two weeks afterwards if tin- weather is not too hot. '(4) Is home, made lime sulphur or the commercial article most in use'.' Answer : Commereal lime sulphur is used- most. (5) 'Do you consider a crop clean with 25 per cent, of scab? Answer : We don't consider the crop clean if over 5 per cent, of scab. (fc>) Do s'Towers thin out to obtain size and quality? Answer : ({rowers thin to obtain size, one or two in a cluster, according to the tree or limb. (7) Would- you consider 50 per cent, of rejects from all causes a clean crop? Answer : Culls as a rule run from 10 to 20 per cent, in first-class crops. 18, Ts it possible to absolutely check scab or black spot? Answer : It is possible to reduce scab to a minimum, less than 5 per cent, under any weather condition. (9) Do yon know of growers who have no uncertainty as t<i their ability to check and keep under control this disease ? Answer : T have never exceeded 5 per cent, of scab in my orchard in 14 years. (10) Do any growers in Hood River have to spray as many as seven times with lime sulphur, either -alone, or in combination with arsenate of lead? Answer : T spray seven or eight times- — the semi-dormant, and pink with lime sulphur : Calyx, lime .and sulphur and arsenate of lead ; second codlin moth spray six weeks after calyx arsenate of lead, including Bordeaux for scab and anthracuose. (It; 'Dries burning occur after using li:ne sulphur? Answer: Burning occurs after the use of lime sulphur if weather following is too hot. Mr K. F. Shepard further states that methods and remedies are nearlv the snme. in all sections, vol there are differences for climatic c orriitions. dates of sprayings, numbers nf sprayings and strengths of sprayings., and all these varv to a greater or less extent. -Mr Shepard savs if you .are in doubt consult the horticulturists in your own localities. In Hood River three sprayings for codlin are ample, but in other districts lour or five are .frequently considered r}eeessar\.

On the subject of black, spot Mr T. \V. Kii',.: was good enoimh to Teply to

the following questions which T sent to him : I -<o you consider the Government formula for black spot i s a reliable control if properly applied? | Answer: There is no doubt that spraying j s effective so long as othei '• matters, such as thoroughly turning un- | der the old .oliage. .etc.*. before the; blossoms appear, keeping the trees open and well ven ti la'. 1, etc., are properlyattended to. The most important application is w.ien Lie buds show colour or the most advanced burst into bloom. At the same time, a strong application when the. buds, begin to swell is bighly desirable. Summer applications are also necessary according to the climatic conditions prevailing. There is no fungicide equal to Bordeaux mixture, and this can be safely used for the first two sprayings, that is. when the buds' begin to swell and for the colour bud spray. (For later sprayings lime sulphur is a good substitute for Bordeaux as a preventive so long as the weather conditions are not too unfavourable, _b-.it if the weather conditions are bad', or should, black spot actually make its appearance, Bordeaux should be restored to despite the risk of russeting some of the tender skinned varieties of apples. Russety fruit, although objectionable, is infinitely preferable to scabbj. fruit. (2) As many growers say they have tried it and failed, where do von think •- fault lies?

Answer: The failure of spraying is mainly due in one way or another to the orchardist himself. Some work too much on a rule of thumb principle, failing to intelligently adapt their work to suit the particular climatic conditions that prevail. Some do their work, in a very careless manner, whilst others do this unknowingly, an J at the sime time do their work under the fixed impression that they are scrupulously carrying out the directions they have received. Others again, spray well, but stilJ fni! owing to the fact that they have neglected to assist their spraying treatment by de. : stroying the whole of the previous season's foliage, by not keeping their trees sufficiently open to a Mow thorough ventilation, and above all by not removing and destroying all diseased and dead, •wood. This is an important precaution, partirularlv in a wet season. Spores arising from affected wood fall on fruit and foliage, on which the spray has bee? washed ou or considerably weaken ed by Tains and affectation takes place*

No doubt those orchards rejKnted to have been more or less free of the disease, last s,eason. without spraying, owe. their comparative immunity nior«* to careful pruning than to any othw cause.

A correspondent to the Fruit World says_J nat a late spraying with Bordeaux is never advisable, and lie goes on to outline the Bordeaux-oil experiment already referred to. The oil used m every case was Gargoyle prepared red spraving oi'. because th 0 grower had previously demonstrated that this oil could be used with safety even when the*bud growth was forward. The experimenter. .Mr -Meiers, now of Bathurst F.x peri mental Farm, claims that lie always had the best of results. Visitors to his orchard noting the line appearance of the fruit treated with fh* double spray were led to speculate whether we were not upon the eve i>:' a revolution ii> the treatment of the biacVspot disease.

The above spray ■would be undoubtedly economical in a saving of time, and ;i!so in the cost of spray material. Mr Chairman and gentlemen, whilo on tho sunject of cost of spray material, it might interest you to know that it-

cost me last season for lime sulphur at the rate of 2d per tree, for arsenato | of lead Id per tree, and, for oil perl tree, or a spraying cost per tree of 6d..' including labour. '' To sum up the whole matter, my lasC two season's spraying schemes have given such good results and that in most unfavourable climatic conditions, that I am led to believe I could not do better than to attain continue with lim e sulphur for black spot and powdery mildew (Bordeaux proving most ineffective against powdery mildew), arsenate of lead for codlin" moth and leaf roller and Gargoyle prepared red spraying oil for woolly aphis.

At tn e ' same time extensive experiments are being conducted in my orchard with atomic sulphur and naphthalene lime sulpnur and again Bordeaux for black spot. A a it may interest my hearers, I have drawn up my spray list for the year in a tabulated "form. * This complete spray list is shown belojw. In mixing lime sulphur and arsenate of lead the procedure is as follows :—ln one 4-galion bucket dilute tne lime sulphur to be used to that extent, 4 gallons. Next slack: 3 or 41b of quicklime and, dilute to 4 gallons. This is poured' off into another 4-gallon bucket containing 31b» of arsenate of lead paste worked down to the consistency of thin cream. ' Thesf two buckets, the dilute lime sulphur and arsenate of lead and limcwaler, are then poured into the spray barrel, runnin™ together. The spray barrel to contain a full supply of water. The limf used has a tendency to neutralise tli* hur»in.s effect of the'water soluble form* of arsenic :

■COMPLETE SPRAY LIST j (Apples and Pears.) Application : 1. Delayed Dormant. Insect and Disease: Black Spot, Mildew, Aphis. Materials and Time -. For Spot: Lime sulphur 1-20 to 25, 32dng. test. If Aphis bad; add Tobacco 1-1200-Spot and Mildew : Lime sulyhur 1-50 to 2. Pink.—Black Spot, Mildew.—For 60 I 3. Calyx.—Spot. Mildew. Codhn. — For S'sot": Lime sulphur 1-60 to 80. For Moth: Add Arsenate of lead 31bs to 100 with lime. 4. Ten days after Calyx.—Spot, Mil- f dew.—For Spot : (Lim e sulphur 1-80 to 100. -dd Arsenate of lead' with lnnA. ' 5. Thirtv days after Calyx.—Spot, Moth, Woollv Aphis.—For Spot: Lime sulphur 1-100" to 120. Add Arsenate of . lead 31b.=? to 100 with lime. Add, Tobacco if aphis sffows. , ! fS. December. —Spot, Moth. —Lime sul- ' phur, plus Arsenate of lead with lime. 7. January Spray.—Spot, Woolly Aphis, Moth," Lea"f Roller. — LiincV sulphur 1-120 if necessary. ArspnateYof lead 31bs to 100 with lime. Add To- ; banco if necessary 1-1200. 8. Februarv.—Leaf Roller.—3lb Ar°cnatr, $f lead to 1.00 with lime. Add Lime sulphur if necessary. 9. March. Last Codlin Sprav.—Moth, Leaf. Roller. Late Spot.—3lbs Arsenate of lead with lime just before picking. Add Lime sulphur if necessary. .10. Autumn Oil.—Woolly Aphis.— Most important aphis spray. Oil 1-60 jiist after fruit picked. Th c above adapted for >Stokc conditions and used successfully through two wet seasons. I