ORCHARD PESTS AND DISEASES: DIRECTIONS FOR CONTROL.

New Zealand Journal of Agriculture, Volume XVIII, Issue 3, 20 March 1919, Page 182

ORCHARD PESTS AND DISEASES: DIRECTIONS FOR CONTROL.

The Department’s Bulletin No. 57, “Principal Spraying-compounds: Directions for Preparation,” has been recast, and is being reissued as Bulletin No. 82, with the title of “Orchard. Pests and Diseases: Directions for Control.” No. 57 will be allowed to lapse. For general information and further publicity the text of the new bulletin is also printed in the Journal, as follows : —

CODLIN-MOTH, LEAF-ROLLER, PEAR - SLUG, ETC.

ARSENATE OF LEAD.

Use not less than 1J lb. arsenate-of-lead paste or J lb. of arsenate-of-lead powder to 50 gallons of water. Commence spraying as soon as the majority of petals have fallen, and repeat the application at intervals of about twenty-one days throughout the season, the main object being to keep the fruit and foliage thoroughly covered with the spray.

RED MITE, MUSSEL, SAN JOSE, AND OTHER SCALE INSECTS ; AMERICAN BLIGHT AND OTHER APHIDES, MEALY BUG, THRIP, ETC.

(1.) For Use in Winter and Early Spring.

RED-OIL EMULSION.

•' For application while deciduous trees are in a dormant state. Apple, pear, and quince, 1 part to 10 or 12 parts of water. (In some districts of the South Island 1 part of oil to 8 parts of water is considered more satisfactory.) Plums, 1 to 12. Other stone-fruits, 1 to 15. ’ Citrus fruits, 1-35 to 1-40. Apply and repeat once or twice at short intervals when the young scales begin to move. This may be looked for from October onward, according to the variety of scale. There are numerous brands of commercially prepared oils on the market needing only the addition of soft water to make them ready for use. It is advisable to dilute in the proportions recommended above, as the strength stated on the container labels are often too weak to give satisfactory results. ■ ,

PREPARATION OF OIL EMULSIONS.

(a.) Proportions 1 gallon oil to 1 lb. soft-soap and 10 to . 15 gallons water according to requirements. .

’ Preparation: Place the oil and soap in a vessel; heat over a fire until the soap is dissolved; remove from fire, and with spray-pump ; thoroughly agitate the contents, at the same time slowly adding J gallon of water. Add balance of cold water, and the mixture is ready for use. •

(&.) Proportions : 1 gallon oil, 2 lb. common soap (home-made caustic-soda soap may be used), 10 to 15 gallons water according to requirements. Preparation : Dissolve soap in 1 gallon of boiling water, and. while boiling pour slowly into the oil, agitating ell; then add balance of water. In the case of thick oils difficult to emulsify this method may be improved as follows : Pour only half the dissolved soap into the oil, and bring to the boil, and allow to .simmer for about five minutes, stirring well ; pour the remainder of dissolved soap into the bulk water, then slowly add this to the oil, particularly the first gallon or two, agitating thoroughly. It is imperative with both formulae that the water used should be soft. Where it is questionable, add 2 oz. of washing-soda to every 5 gallons of water. Rainwater is always to be preferred for the mixing of spraying-compounds.

(2.) For Use in Late Spring and Summer.

KEROSENE . EMULSION

A spring and early summer remedy for scale and thrip on citrus and deciduous fruits.'

Proportions : Kerosene, 2 gallons ; common soap, | lb. ; boiling water, 1 gallon. Preparation : Place the soap in the water, which should by preference be rainwater. Hard water is unsuitable, but if only such is to be had, make it soft by adding some soda. Boil till the soap is thoroughly dissolved; then take it off the fire and pour the solution into the kerosene. Thoroughly churn up by placing both suction and delivery ends of the spray-pump hose in the liquid and pumping steadily for a few minutes ; the emulsion should then, if perfect,- form a cream, which thickens on cooling without any appearance of free kerosene. For most plant-lice (aphides) and other soft-bodied insects, from, 12 to 20 parts of water are added to one of the emulsion. • •

“ vistolene!”

A contact insecticide valuable for destroying plant-lice, especially the black aphis of the peach. Recommended for use_in the ratio of 1 to 100.

“ MCDOUGALL’S INSECTICIDE.”

This specific, used in the proportion of 1 part to 50 parts of water, has also proved effective in controlling black aphis of the peach.

“ KATAKILLA.”

This is a contact insecticide useful for the control of black aphis and other soft-bodicd insects. Use in the proportion directed on the packets.

"blackleaf 40 ” (nicotine SULPHATE).

A nicotine preparation, valuable for summer use in controlling woolly aphis, red mite, &c. It can be used in the proportion of i part of Blackleaf 40 to 800 parts of water. ■ Three to four pounds of dissolved soap to every 100 gallons of diluted wash considerably increases : the, efficiency of nicotine sulphate. Soap, however, should not be added when nicotine sulphate is being used in combination with other compounds.

PARASITIC FUNGI GENERALLY, ESPECIALLY THOSE ATTACKING STONE-FRUIT.

BORDEAUX MIXTURE.

Proportion : 8 lb. sulphate of copper, 6 lb. fresh quicklime, and 40 gallons water.

Preparation : Dissolve the sulphate of copper in 20 gallons water ; slake the lime slowly, and make up to 20 gallons ; pour both solutions simultaneously into a third vessel.

Bluestone is readily soluble when placed in a piece of sacking and allowed to touch the surface of the water or suspended an inch or two below it, or by using hot water. The efficiency of bordeaux depends upon the intimate blending of the two solutions, obtained by pouring both solutions simultaneously into a third vessel. It is imperative that the chemicals used be pure, the lime fresh and having a high percentage of calcium oxide. The best results are obtained when the application is made as soon as possible after blending the two solutions. If allowed to stand over eight hours its fungicidal properties largely depreciate. In the case of peach, nectarine, and apricot, apply when buds show colour, and for apple and pear when the buds are bursting.

BLACK-SPOT OF APPLE AND PEAR.

BORDEAUX MIXTURE (SPRING FORMULA)

Proportions : 6 lb. sulphate of copper, 4 lb. fresh quicklime, 50 gallons water Preparation : As for winter formula. Apply when cluster-buds are expanded and showing colour.

PURE BLUESTONE.

The use of pure bluestone (sulphate of copper) has become popular in some fruitgrowing countries as a fungicide for winter use. It has so far proved satisfactory in the Dominion, and may supersede the bordeaux mixture (winter formula), used in the proportion of i lb. of bluestone to io or 15 gallons of water for pip-fruits, and 1-15 to 1-20 for stone-fruits.

DUAL-PURPOSE SPRAYS (INSECTICIDE AND FUNGICIDE).

COMMERCIAL LIME-SULPHUR (SPECIFIC GRAVITY 33 0 BEAUME)

This is beneficial in controlling fungus diseases, particularly powdery mildew, and is also useful as a summer spray for red mite and other soft-bodied insects. Late winter or early spring strength : Pip-fruits— 1-10, when buds are bursting ; stone-fruits — when buds show colour. Spring or early summer strength Pears 1-15 to 1-20, when buds show colour; apples—1-25 to 1-30, when buds show colour; stone-fruits 1-125, when fruit has set. ' ' -

Summer strength : Pears1-80 to 1-100 ; apples1-100 to ,1-120 ; stonefruits —1-125. ' -

The several brands of commercial lime-sulphur are supposed to be of a standard strength, but considerable ' variation has been found in different barrels of the same brand, and further, through settlement, different specific gravities have been noted in the same barrel. This applies particularly to the home-made article. Where possible stir the vessel well before drawing off, test frequently, and dilute according to the table on next page.

SELF-BOILED LIME-SULPHUR.

Another form of lime-sulphur is the self-bdiled mixture. Although this is not such an effective fungicide as the commercial or ordinary home-made article, it provides a useful alternative for use on the more tender-foliaged varieties of trees. The standard self-boiled lime-sulphur mixture is composed of 8 lb. fresh stone lime and 81b. sulphur to 50 gallons water. Any finely powdered sulphur (flowers, flour, or “ commercial ground ” sulphur) may be used in the preparation of the mixture. In order to secure the best action from the lime the mixture should be prepared in rather large quantities, at least enough for 200 gallons of spray, using 321b. lime and 32 lb. sulphur. The lime should be placed in a barrel, and enough' water (about 6 gallons) poured on to almost cover it. As soon as the lime begins to -slack, the sulphur should be added, after running it through a sieve to break up : he lumps, if any are present. The mixture should be constantly stirred, and more water (3 or 4 gallons) added as needed to form at first a thick paste and then gradually a thin paste. The lime will supply enough heat to boil the mixture several minutes. As soon as it is well slaked water should be added to cool the mixture and prevent further cooking. ..It is then ready to be strained into the spray-tank, diluted, and applied. The stage at which cold water should be poured on to sop the cooking varies with different limes. Some limes are so sluggish in slaking that i. is difficult to obtain enough heat from them to cook the mixture at all, while other limes become intensely hot on slaking, and care must be taken not to allow the boiling to proceed too far. If the mixture is allowed to remain hot for fifteen or twenty minutes after the slaking is completed the sulphur gradually- goes into solution, combining with the lime to form sulphides, which are injurious o peach-foliage. It is therefore very important, especially with hot lime, to cool the mixture quickly by. adding a few buckets of water as soon as the lumps of lime have slaked down. The intense heat, violent boiling, and cons ant stirring result in a uniform mixture of finely divided sulphur and lime with only a very small percentage of the sulphur in solution. It should be strained to take out the coarse particles of lime, but the sulphur should be carefully worked through the strainer. ‘ <

COMBINATION SPRAYS.

When desired the following sprays can be used in combination : Arsenate of lead and bordeaux ; arsenate of lead and lime-sulphur solution ; arsenate of lead and Blackleaf 40 ; arsenate of lead, lime-sulphur, and Blackleaf 40. Care should be taken when combining arsenate of lead with lime-sulphur. It is advisable to make a heavy dilution of both before mixing. To ensure maximum safety against damage to foliage add a dilute solution of lime to the arsenate, using approximately the same weight of lime as arsenate of lead.

is specific and a by of in any select the line cross-line of specific equal of (The self-boiled to , apply

Beaume. IO. r-15. 1-20. 1-30 1 .1-40. ,, 1-50. 1-60. 1-70. : I—80. i v 9O. I-IOO. 1— 110. 1-120. 1-125. 1-30-1—40. 1-50. 1—60. 1-70. 1-80. 1-90. I-IOO. 1-1 10. I —120. 1-125. i5° ... 4-6 6-8 1 • • 9-1 II-4 13-6 18-2 22'8 27'3 31'8 36-4 40'9 45'5 5o-o 54'5 56-8 9-1 fi-4 13'6 18-2 22-8 27'3 31-8 36’4 40-9. 45’5 50’0 54'5' 56’8 i6° 4-8 7'3 97 12'1 i4'5 19'4 24'3 29-1 33'9 38-8 43'6 48'5 53'3 58-2 6o-6 0 17 5’2 77 10-3 12'9 ;75'5, 20-6 25'8 30-9 36-1 : 41-2 46-4 54'5 567 6i-8, 64'4 i8° 5'5 8-2 10-9 13-6 16-4 21-8 27'3 327 38-2-43'6 49-1 54'5 6o-o .65’5 68-2 0 19 8-6 ii'5 ..14-4- ' I7..3 . 23’0 28-8 34'5 49’3 .46-1 51'8 57'6 63'3 69-1 72-0 i 5’8 8-6 ii'5 14-4 17'3 23'0 28-8 34'5 40'3 46-1 51'8 57'6 63'3 69-1 72-0 20° 6-i 9-1 I2-I 15'2 18-2 24-2 30’3 36-4 42'4 48'5 54'6 6o-6 667 727 75'8 ; • ,?■ 6-4 : 97 12’7 925'5 31'8 38-2 44'5 50'9 ■57'3 63-6 70-0 76'4 79'5 22° -67 io-o 13'3. 167 20'0 26-7 33'3 40-0 467 53'3 60-b. 66-7 73'3-8o-o 83'3 '' O 23 . .7-0 ip-5 13'9 17.4 20-9 27'9 34'8 .41-8 48-8 755'8 627 69'7 767 83'6 87-1 24? . '7:3 : 10-9 14'5 -2 -8 21, 29-1 367 43’6 507; 58-2 65'5 727 8o-o 87'3 90'9 0 25 7-6 ii-4 15'2 ' 19-0 227 30-3 37'9 45'5 ’0. 53,• 6o-6 68-2 75'8 83'3 90-9 94'7 < 26° : .. 7.9 n-8 15'8 197 23-6 3i'5 39'4 47'3 55'2 63-0 70'9 78-8 86-7 94'5 8 9 ; 8-2 12-3 16-4 20-5 ' 24-5 327 40'9 49-1 : 65-5 73'6 8i-8 90-0 98-2 102-3 28° 8-5 12-7 17-0 21-2 25'5 33'9 42'4 507 : ! 59'4 67'9 76-4/ 84-8 93'3 ioi-8 106-1 0 29 8-8 13-2 17-6 22-0 26-4 35'2 43'9 527 61-5 ; 3 7O 79-1 87'9 96'7 105-5 x -8 30°. ■ . , . 9-1 13-6 8-2 22-7 27-3 36-4 45'5 54'5 63-6 72-7 8i-8 90'9 100-0 109-1 113-6 3i° •• 9-4 14-1 18-8 ; r 28-2 37'6 47'0 56’4 ■65-8 75'2 84'5 93'9 103-3 1127 117-4 32° : . 97 14'5 19.4 ' 24-2 29-1 38-8 48'5 58’2 67-9 77'6 . 87'3 97'0 1067 116-4 I2I-2-33° 4-io-o 15-0 20-0 25'0 30-0 40-0 50'0 6o-o 70-0 8o-o 90-0 100-0 iio-o .120-0 I25-O 34° 10-3 15'4 ■ 20-6 25'8 30-9 41-2 57’5 6i-8 72-1 82-4 927 103.0 U3'3 123-6 128-8 35° io-6 15'9 21-2 26-5 31'8 42-4 53'0 63-6 74'2 84-8 95'5 106-1 116-7 127-3 132-6

REFERENCE TABLE FOR STANDARDIZING HOME-MADE LIME-SULPHUR SOLUTION BASED ON A 33° BEAUME STANDARD.