355 ORCHARD PRACTICE HUNTLEY 906 or c, Main Lib. AURIC, DEPT, A BULLETIN ORCHARD PRACTICE JOMPIL F, A. HUNTLEY State Commissioner of Horticulture TACOMA, WASHINGTON, March, 1906. OLTMPIA, WASH, 1 . GORHAM, PUBLIC PRINTER. 1906. A BULLETIN ON ORCHARD PRACTICE COMPILED BY F. A. HUNTLEY State Commissioner of Horticulture TACOMA, WASHINGTON, March, J906. OLYMPIA, WASH. C. W. GORHAM, PUBLIC PRINTER. 1906. ACKNOWLEDGMENTS* This bulletin is not intended to appear as an exhaustive treatise on the subjects presented, but its aim is to serve as a brief guide for those who are in need of such information. Professors W. H. Lawrence and A. L. Melander of the State College have very kindly furnished the articles for this publication, which are credited to them, and what they have to say is fresh and up to date. Main Lib. AGR1C, DEPT. A BULLETIN ON ORCHARD PRACTICE. PRUNING ORCHARD TREES. BY F. A. HUNTLEY. Pruning is indispensable to the profitable cultivation and training of fruit trees and plants. Nature prunes and trains in a crude fashion but does not cultivate. Cultivation breaks into the natural habits of plants, intensifies development, and causes a demand for more intensive processes. Natural con- ditions and artificial methods are wholly different and op- posed in their application. Take fruit trees or plants of any kind, which have been established in variety form by methods of propagation and cultivation, and subject them to natural conditions, namelv that of neglect, and they will usually revert to a lower constitutional vigor than their immediate ancestry. To maintain high standards in cultivated plants it is, there- fore, necessary to fulfill all the requirements of domestication. The purpose of this article is to give a few hints on the pruning of orchard trees. Limited space here forbids going at length into details. No attempt is made on the subjects of pruning vineyards and small fruits, as these are matters ex- tensive within themselves. There are many reasons why trees and other plants are pruned, and there seems to be a general demand for enlighten- ment upon this important subject. Pruning is done on young trees to start an even balance of root and top at the time of transplanting. Trees two years old and over, especially, suffer considerable loss at the roots when taken up for transplanting, and it is usually advisable to reduce the tops to correspond. A reduced root system will not well maintain the vigor of a normally developed top. Again it is advisable to prune young trees to establish shapely form. The ideal is the yearling tree to commence with, for it is then possible to shorten the single stem to the A Bulletin on Orchard Practice point where it is desired to form the head, or establish a sys- tem of branching. This can be done also with an older tree, and is usually necessary, as the commercial kind is generally two years old or over at the time of transplanting. Do not be afraid to cut the young tree back to the height desired. Low heading of fruit trees has come to be an almost universal practice and there are a number of good reasons for this. Tops low down admit of economy in harvesting the fruit, ease and effectiveness of spraying, convenience in pruning, shading the ground at the base of the tree and thus conserving moisture, less exposure to winds, protection from sun scald; and if a tree is properly pruned during its young life it will maintain a more open habit of branching throughout its existence than a "tassel top" which is the natural tendency in high heading. "As a rule, all apple, pear, and sweet cherries ought to be headed not higher than twenty to twenty-four inches from the ground, and all stone fruits, such as plum, prune, apricot, peach, nectarine, etc., may, with advantage, be headed a little lower, say twelve to fifteen inches from the ground." The pruning of bearing apple orchards is a subject upon which, nerhaps, more are interested than any other in the line of pruning. It has for its objects the renovating of old trees, thinning to facilitate spraying and to admit light, and the removal of injured, crooked and crossed branches. It is also desirable to maintain symmetry of growth. It is too common a mistake to neglect pruning for several seasons and then to over-prune at one time. Pruning is usually done in late winter and early spring, before the buds swell, and is the proper time as a rule. Pruning should be done every season, and not much at a time. Avoid cutting off large limbs ex- cepting in cases of evident necessity. The effect of removing much wood growth in the dormant season is to direct the en- ergy of the tree to making new wood which will appear as "water sprouts" and long succulent branches. Always cut close to the base when taking off limbs. Do not leave stubs, as they may require a season or two to die back to the base before the wound will commence to heal and cover the injury. In the meantime decay may set in and injure the main stem upon which the cut was made. After wounds have remained exposed long enough, a few days after pruning, so the sur- A Bulletin on Orchard Practice faces may dry, they should be covered with some kind of dress- ing to exclude air and moisture and prevent decay. Wax, varnish, or paint, may be used for this purpose. Thick white- lead paint is one of the best dressings, and is easy to apply. Make clean cuts with a sharp pruning saw, pruning shears, or a sharp knife. The size of cut to be made will determine the tool to be used. Pruning the tree during the active stages of growth dis- turbs the harmony of action between roots and top and causes a check to the wood development. In other words, summer pruning tends to dwarf hard wooded plants. Prof. J. A. Bal- mer makes comparison of the effects of winter and summer pruning as applicable to the extreme eastern and western sec- tions of this state, in the following: "Let us first observe the conditions prevailing in Eastern Washington." (Above the irrigated valleys.) "Here we have a long, dry summer, with a fierce, scorching sun, and strong, drying winds, with a maximum rainfall of probably less than eighteen inches per annum, followed by a severe winter with fluctuating tempera- tures, and sudden changes. In portions of the fruit belt there is barely enough natural moisture in the ground to sustain a tree. Under these conditions who can wonder that trees on the east side come to maturity at an early age, and produce fruit at a time in their lives when they ought to be making wood growth, and establishing a strong, healthy frame for future usefulness. There is no question in my mind, as to what is the proper method to adopt in pruning our fruit trees on the east side of the mountains. We must prune in the win- ter and prune hard. The tendency of all our young trees is to run to premature fruiting. Cherries carrying a crop of fruit at two years old, and pears and apples bearing full crops at five and six years old. To overcome this tendency in our trees we must practice a system of pruning that is con- ducive to wood and leaf growth, and to discourage all forms of summer pruning and pinching." "Trees on the west side of the mountains should be treated a little differently. In most sections on the west side, and especially in the warmer valleys, trees make an extraordinary wood growth. It is no uncommon thing to find young prunes and cherries making a growth of six to ten feet in a single 6 A Bulletin on Orchard Practice season. The excessive moisture in soil and atmosphere, and the mild climate, are conducive of this rapid growth. Trees grow late in the season, and there is some difficulty in secur- ing thoroughly ripened wood. To cut back severely in winter aggravates the evil, more and longer wood is the result. The way to check this excessive growth is to resort to summer pruning and pinching and even to root pruning." All of what has been said is applicable to plants in general. It may be well to add a little specifically about certain fruits. The apple is generally regarded as a tree of greatest per- manence. With this in view it becomes a matter of importance to take into consideration a long future development. Low heading has been indicated as a preference. An even balance of top on all sides is desirable. About three, and not to exceed four main branches should make up the frame structure. If the lowest branch starts at twenty-four inches above the ground line, then the second branch should begin not less than six inches above the first, and so on. In the old tree, with its greatlv increased diameter, the branches will then seem to be- gin at very nearly the same point. If the tree is to have three main branches they should be selected to alternate from about three equal sides of the trunk to insure symmetry of form and correct balance in the weight of top. The after-pruning should be directed towards maintaining this balance and sym- metry throughout the life of the tree. A very little pruning each year should suffice thereafter. The pear tree requires about the same treatment as the apple, with perhaps a little more freedom in branching as in the case of some varieties of erect habit. By some growers it is considered advisable to shorten each of the main branches to about one-third its length after the first season's growth, and continue this shortening process until the tree comes in bearing. A young pear tree is inclined to produce a great many fruit spurs along the main branches. These should be kept rubbed off. If the trees are of great vigor it should be done in the summer but if growth is only moderate the winter is the best time. The main object in this is to insure smooth, clean branches, which is a protection from disease. It has been fully demonstrated that pear blight gains entrance to a tree through the blossoms by the visits of insects from in- A Bulletin on Orchard Practice fested trees. If flowers appear only on the smaller growths the diseased limbs can be cut out with little damaging results. The peach tree is a rapid and vigorous grower. The fruit is always borne on wood grown the previous season. Fruit spurs are not formed as in the case of the apple and pear. One-year-old trees are the most desirable for planting. Most growers prefer heading the trees only a little above the ground line, with three or four main branches. The annual growths are usually very long, and until the tree comes into full bearing it is best to practice shortening back considerably each annual growth earlv in the spring or late winter. In fact the heading back process should always continue, to insure compact, shapely trees and a uniform distribution of fruit. Systematic annual pruning is much to be preferred to the practice by many of neglecting to prune for a number of seas- ons and after a few years starting a new head by cutting the top back to a mere stump. Such cutting back seldom produces satisfactory results. The cherry, and also the plum, should be pruned but very little after a system of correct branching has been started. Sometimes it happens that a vigorous side branch will start and grow to excessive length in the young sweet cherry, and plum. It is well to head back such branches in the growing season to a proportionate length. Prune also to avoid the formation of sharp crotches which are apt to separate in the aged tree. Crotches are likely to form where two branches of equal vigor are allowed to develop from the same point. If one of them is headed back the effect will be a much stronger union, because of the fact that one outgrows the other. Deep cultivation of the soil in orchards is in effect a sys- tem of root pruning. It can be practiced to good effect among trees inclined to heavy wood growth, as it encourages the for- mation of fruit buds instead of wood. Where the object is to stimulate wood growth cultivation should be very shallow and frequent. Clean cultivation is always desirable whichever re- sult is sought, that of wood growth or fruit production. A Bulletin on Orchard Practice THE CODLING MOTH AND ITS TREATMENT. BY A. L. MELANDER. The Codling Moth is a brownish miller about one-half inch in length, which lays eggs on or near apples. In a little over a week the eggs hatch into Codling Worms. In nearly all localities two distinct broods of worms occur each year. After feeding within the apple for several weeks the worms leave the fruit to cocoon. Most worms make their cocoons in the ground, many can be found ben.eath rough bark. The I U Different Stages of CODLING MOTH — all natural size. cocoon stage is completed in from two weeks to a month dur- ing the summer. Worms leaving apples late in the summer remain in the cocoons over winter. When the cocoon stage is completed the Codling Worm has changed to the Codling Moth, and is ready to lay its eggs. HOW TO COMBAT THE CODLING MOTH. The only remedy for the Codling Moth is spraying. Other measures are useful but can not be depended on alone. Clean culture, especially stirring up the ground beneath the trees, is of great importance as it destroys the worms in their cocoons. Banding trees with burlap will' trap 40 per cent, of the worms. A Bulletin on Orchard Practice 9 Apples should be thinned so that no two touch. Trees should be pruned so that they can be easily sprayed and cultivated. A new orchard should be set with trees thirty feet apart to allow for passage for the spraying outfit in the future. SPRAYING. After the Codling Moth has entered the apple spraying does no good. The object of spraying is to provide a coating of poison through which the worm will have to eat its way. Many worms enter where apples touch. If the fruit is thinned so that no two apples touch the worm is more likely to get poisoned. Most of the early worms enter apples at the blos- som end. In order to place poison in the blossom end a spray- ing must be given just after the petals fall and before the calyx cup closes. This will be several weeks before the first worms are hatching but must be given. It is the most import- ant spraying of all. The other sprayings should be given just as the first worms of each brood are hatching. HOW TO TIME THE SPRAYINGS. The time for the first spraying is definitely fixed. But there is more doubt as to when the other sprayings should be given. The best time for spraying can be easily ascertained by the following simple method. In a quart glass jar place a num- ber of cocoons obtained from the trunk of an infested tree. This jar should have a cloth cover and should be placed in the shade in the orchard. Add ten days to the date when the moths first appeared in the jar, to allow for the hatching of the egg and the date for the second spraying is obtained. Ob- tain some new cocoons a month or so later and rear the moths of the second brood in the same way. The date for the third spraying is thus found. A fourth Spraying should be given one month after the third in the warmer localities. WHAT TO SPRAY WITH. Lead arsenate is giving better satisfaction than any other substance. Lead arsenate can be obtained on the market most economically as Swift's Arsenate of Lead or as Disparene. Mix two pounds of lead arsenate paste with fifty gallons of water. Give three or four sprayings, which are necessary. One spraying alone will do no good. 10 A Bulletin on Orchard Practice Lead arsenate sticks well and shows up well on the apple. An ordinary rain will not wash it off. It can not scorch. It has given such good results that it is the cheapest insecticide in the long run. If lead arsenate can not be obtained use one pound of Paris green to 125 gallons of water. Add the Paris green to two pounds (no more) of freshly slaked lime in mixing. Keep this mixture constantly agitated while spraying. HOW TO SPRAY. Be thorough. One spraying properly done is better than a dozen incomplete sprayings. Every side of every apple CODLING MOTH LARVA. must be sprayed. If an apple is only partly covered it will probably become wormy. Use as much force as possible; the mixture will penetrate hotter, spread better, and stick better. The one object of the ,$rst spraying is to get poison into the calyx cup. To do this it is necessary to force the spray through the crown of stamens. Spray downwards into the flowers with all the force possible until the flowers are drip- ping. An angle at the end of the extension rod is a conveni- ence. The other sprayings must be made crosswise and up- wards, as the aim is to coat the fruit with poison. Use what- ever nozzle will break up the spray into a mist with the pres- sure available, — Vermorel for hand pumps and the Bordeaux A Bulletin on Orchard Practice , 1 1 type for power. The best results have been obtained by using the power pump and throwing plenty of a rather coarse pene- trating spray. By this means from 90 per cent, to almost the entire crop should be saved. But above everything else, be thorough. SAN JOSE SCALE. The San Jose Scale has become so generally distributed to the fruit sections of this state that most growers of tree fruits are familiar with its destructive effects. It may be SAN JOSE SCALES — enlarged about three diameters. found on all kinds of fruit trees, and on native trees con- tiguous to the infested orchards, but is most noticeable on apples and pears. When present on a bearing tree it al- ways attacks the fruit, causing conspicuous red blotches. Most persons do not like to eat scaly fruit. Raw animal mat- ter has not come to be a coveted relish when served upon fresh fruit, or otherwise. The San Jose Scale does not appear in broods at stated intervals, as is the habit of some other insects. It lives through the winter on branches and twigs from the infant stage to that of full development. The scales as observed 12 A Bulletin on Orchard Practice during the dormant season are from about a thirty-second to nearly one-eighth of an inch in diameter. They are of a grayish color, nearly circular in shape, and almost flat, with a pointed, slightly raised center of lighter color. They devour the vital forces of a tree to such an extent that it ceases to be profitable, and will finally die if left untreated. Beginning with the first warm weather in May the scales commence to multiply and so continue to increase through the season. The young are born alive and become immediately active in their destructive work of sucking the juices from the plant. It is not a difficult matter to control and even to eradicate this pest from an orchard, by use of the sulphur-lime spray properly prepared and thoroughly applied. The writer of this article has used the sulphur-lime spray in June with excellent success by applying the standard formula made up to one-half strength. F. A. H. OYSTER-SHELL SCALE. The Oyster-Shell Scale, so common west of the Cascade mountains, has a different life history from that of the San OYSTBB-SHEL.II SCALES — enlarged about three diameters. A Bulletin on Orchard Practice 13 Jose Scale. It winters in the egg stage, the eggs being pro- tected until they hatch in the warm spring weather, by the shell or dead covering of the old scale. Otherwise they are similar in their destructive habits. The same treatment ap- plies to both. Mr. E. S. Ridge, Fruit Inspector for Pierce county, and many others as well, testify to the effectiveness of the Sulphur-Lime Spray for the Oyster-Shell Scale, when this solution is made and used properly. F. A. H. APHIS (GREEN AND BLACK.) The aphis which attacks the foliage of the apple is usually of a light green color, and those found on the plum and other stone fruits are commonly black. Many kinds of plants are infested with aphides of varying shades of green merging to black. The females give birth to living young through the summer. Near the close of the warm season eggs are depos- ited on the twigs, and these hatch the following spring, and so continue the cycle of development. Aphides cause injury to young trees, nursery stock, and newly set grafts, princi- pally by hindering or destroying leaf action. The common remedy is kerosene emulsion used as a spray. The remedy I have found best by extensive practice is a prep- aration of nicotine, a by-product in the manufacture of to- bacco for the trade. This is a syrupy liquid put up and sold in one and five gallon cans, and extensively used as a sheep dip for ticks, and by greenhouse men to kill insects infesting tender plants. It is offered to the trade under the names, Sheep Dip, Rose Leaf, Black Leaf, Nicoticide and other trade names. The cost is $1.00 to $1.25 per gallon and is diluted with about 75 parts water for application. A strong tobacco tea made from the refuse of cigar factories and used as a spray is an excellent substitute for the commercial nico- tine products. A thorough spraying with sulphur-lime solution before the foliage starts will destroy the eggs, thus we gain another im- portant advantage in the use of this valuable remedy which is considered the standard for scale insects. F. A. H. 14 A Bulletin on Orchard Practice WOOLLY APHIS. This insect is rarely found anywhere except on apple trees. It is most common in the Coast Region, though in other sec- tions it is sometimes quite numerous. The white cottony sub- stance which forms a covering and protection to the soft- bodied insects beneath, appears so conspicuous that its pres- ence is readily observed. It attaches itself to rough places WOOLLY APHIS — on root and branches. in the bark, in openings caused by wounds, where branches have been cut off, and about the buds and fruit spurs ori small branches. It impairs the vitality of the tree when al- lowed to develop in considerable numbers. The sulphur-lime spray helps to keep it in check, but kerosene emulsion is a more effective remedy. Pure kerosene applied with a paint brush to the trunk and main branches where it is found seems to result in no injury to the tree and will kill the in- sects. It is a difficult pest to eradicate. It is said that a "root form" of woolly aphis attacks the roots of apple trees. Some authorities claim the so-called root form is entirely a different insect, and it is named the A Bulletin on Orchard Practice 15 "apple-root aphis." While not as common as the woolly aphis working in the tops, it is even more destructive when found. Galls which resemble crown-gall are produced on the small roots by its attack. A remedy recommended for this is to re- move the earth from around the base of the tree and treat with kerosene emulsion. This pest is likely to be introduced on nursery stock and serves as a warning to the planter for close inspection. F. A. H. APPLE-ROOT APHIS — a, Infested Root; 6, Larva; c, Perfect Insect. THE PEACH TWIG-BORER. This insect has come to be a serious pest" in some of the peach-growing communities in this state. The first attack is made upon the young twigs in the spring by the larvae (worms) boring into the tips. A late brood infests the fruit, and it is the late varieties of fruit that indicate the greatest loss to the fruit-grower. The adult is a small dark-gray moth which reaches matur- ity in August and later. The moths lay their eggs in the crotches of the smaller branches. When the eggs hatch the larva bore into the bark and there remain until the following spring. The Kerosene Emulsion Spray will destroy the worms if thoroughly applied late in the winter or early spring. In 16 A Bulletin on Orchard Practice treating for this pest it is advisable to use an elbow on the end of the spraying rod, and direct the spray downward into the crotches with considerable force. F. A. H. APPLE SCAB. BY W. H. LAWRENCE. This is the most destructive disease of the apple that oc- curs in the state. The fungus that causes the disease has SCAB — on the Apple. two stages — the winter stage which lives in the dead and de- caying leaves during the winter and the summer stage which lives on the leaves and fruit during the summer. The form in the dead leaves continues to grow during the winter. Sometime in late winter or early spring capsules are formed inside the leaves. Each capsule contains numerous spores. About the time the leaves on the apple tree begin to A Bulletin on Orchard Practice 17 unfurl in spring and later these spores escape from the capsule and float about in the air. Some of them lodge on the leaves, flowers and fruit. If they germinate they will cause the parts to become diseased. The summer stage then makes its appear- ance in a few days in the shape of small, usually nearly cir- cular, dark, 'olive green colored blotches. These blotches are composed of numerous short stalks on the tips of which sum- mer spores are borne. The summer spores mature at once and drop off. If they lodge on the leaves and fruit of the same tree or a neighboring one thjey will cause new areas to become diseased. Very shortly a second crop of summer spores is produced by the fungus in the new areas which in turn drop off. Some of them are carried by the wind and other agents to the leaves and fruit and thus spread the disease more widely. Summer spores mature in such a short time and are produced in such abundance that thousands of scabby spots appear in the course of a few days when conditions are fav- orable. As the parts mature the new blotches become less frequent and finally cease to appear. The greater number of them appear during the interval of time between the unfolding of the leaves and a few days after the petals have fallen. The reason that the fungus no 'longer produces new diseased areas is perhaps due to the epidermis (skin) of the leaves becoming somewhat thicker and firmer and thus more resistant so that the fungus is unable to make an entrance. Since the fungus that causes the disease winters in the dead leaves it is evident that the destruction of as many of the fallen leaves as possible will materially lessen the number of winter spores to be set free in the spring. Plowing the leaves under in the autumn is perhaps the easiest method of getting rid of a greater number of them. This will not altogether prevent the disease. The trees must be sprayed every year. Several sprays have been used in combatting apple scab but none has given as good results as properly prepared Bor- deaux mixture. Two applications applied on the proper dates are sufficient to hold the disease in check. The first application must be made just before the flower buds open and the second just after the petals have fallen. 18 A Bulletin on Orchard Practice BLACKSPOT CANKER. BY W. H. LAWRENCE. Blackspot Canker is a disease of the apple tree. In im- portance it ranks next to the apple scab. It is very prevalent and destructive in Western Washington in localities where the rain-fall is considerable during the latter part of autumn and early winter. The disease is caused by a parasitic fungus CANKER PATCHES — on Apple Tree Branches. The fungus lives in the bark for about a year and then dies. Before it dies it forms spores the greater number of which are distributed from October to late December or a little later. These spores are carried about by the wind and some of them lodge on the bark of apple trees. The moderately low tem- perature and plenty of moisture usually present in November and later are conditions most suitable for germination. On germinating the fungus enters the bark. Occasionally by the end of a week new cankers make their appearance, They are about the size of a pin head, circular, somewhat sunken, and A Bulletin on Orchard Practice 19 nearly black. They increase slowly in diameter but the fun- gus penetrates the bark into the sap wood beneath. When the tree begins to leave out the cankers increase rapidly in diam- eter and are mature in size by the last of -June or a little later. Mature cankers are usually oblong and vary in size from % of an inch to 6 inches long by % of an inch to 5 inches in width. Frequently they appear to be much larger. As a rule these larger ones are the result of two or more smaller ones merging together. The cankered bark becomes dry and brit- tle and separates from the living, leaving a fissure. It re- mains on the tree for a time and then falls out, leaving a scar. About the time the cankers are full grown the epidermis (skin) on the cankers become slightly roughened by the for- mation of pustules just beneath it. Each of these pustules contains numerous spores which when distributed will cause the new cankers to appear. Since the spread of the disease is caused by spores and the spores germinate in November it follows that the way to pre- vent the disease is to prevent the germination of the spores. This can be done by spraying the trees with double strength Bordeaux mixture about the first of November to kill the spores on the bark. Under ordinary weather conditions there will be sufficient spray on the bark 'to kill spores that may lodge on it for a short period of time if the work has been done properly. To catch the spores that are distributed later in the season spray a second time with double strength Bor- deaux mixture making the application thorough so that the entire tree is covered with the spray. The second spraying should be done two or three weeks after the first. In rainy weather three or more sprayings may be necessary to keep the bark protected. CROWN-GALL AND HAIRY-ROOT. A report of investigations by Mr. George G. Hedgcock of the U. S. Department of Agriculture on Crown-Gall and Hairy-Root, indicates that they are two separate and dis- tinct diseases, which is contrary to the belief by some that these are two forms of the same disease. Much remains yet 20 A Bulletin on Orchard Practice to be learned about these diseases of which the Gall ic the more common. It is found on the roots of various kinds of fruit trees and other fruit-bearing plants, and other plants as well. The above report says, galls often occur in connection with hairy-root, but these are results of wounds rather than a CROWN- GALL — on Apple Root. form of this disease. *Apple crown gall is of two types," says the report. "A hard! callous form is common on grafted trees at the union of the root and scion, and at any other point of the root system where wounds occur in either the cultivation or transplanting of trees." "A second type is a soft form more common on seedlings," meaning seedling stock used for graft- ing. In my opinion this "soft" form may be the same as that designated as the "callous" form, being soft by reason of the softer tissues of young seedlings. All forms of root disease should be rejected and destroyed both by the nurserymen and planters. No remedy for this disease has yet been found, and much concerning it remains to be studied. F. A. H. A Bulletin on Orchard Practice 21 GUMMOSIS. The gummy exudations often seen on cherry trees and other stone fruits, indicate defective nutrition. It is the transfor- mation of large groups of tissue into a waste product with which goes the vital forces of the tree. Young trees suffer great loss of vitality when so affected and will often die. Im- perfect nutrition may be brought about by: excessive moist- ure, poor drainage, a dry subsoil, and a lack of the proper elements of plant food. Cherries should be planted on well prepared land, and attention always given to good cultivation. Wherever gum appears it should be removed, then the parts should be cleaned, and an application 'or two of orange shellac varnish made upon the parts affected. I wish to emphasize the value of this treatment with orange shellac varnish. To prepare the varnish take pure alcohol and add enough orange shellac scales to make a liquid of the density of thick cream. Apply the varnish with a brush. When dry it is re- sistant to moisture. It is well to have the surface dry when the application is made. There is no better dressing for wounds of all kinds on plants than this varnish. It is better than waxes for dressing cut surfaces after pruning. Orange shellac varnish is an antiseptic. F. A. H. PEAR BLIGHT. This disease is sometimes called "fire blight," as an in- fested tree has the appearance of being scorched by fire. The leaves and twigs turn black, and if neglected will continue to die downward. It has been fully determined that pear blip-ht is caused by a species of bacteria, exceedingly minute germs, which gain entrance to the soft growing tissues of the plant through the blossoms or wounds, and circulate in the sap. Bees will carry these germs from an infested tree to others when in bloom. Owing to the nature of the attack, external remedies cannot be made to reach the disease. The only remedy is to cut out the diseased branches, and it is best to cut about a foot below the apparently diseased portion, as a fresh attack does not always have a surface indication. The 22 A Bulletin on Orchard Practice knife or whatever pruning instrument is used should be dipped in a rather strong solution of carbolic acid after each cut is made to avoid spreading the germs by contact. Growers should use extraordinary care to prevent the in- troduction of pear blight to their localities, for sooner or later they are sure to experience considerable loss if it is allowed to spread. F. A. H. BORDEAUX MIXTURE AND ITS PREPARATION. BY W. H. LAWRENCE. Bordeaux mixture is composed of a number of compounds formed by pouring together solutions of bluestone and the milk of lime. The chemical changes taking place are very delicate, and in order that these may take place correctly great care must be exercised in mixing. The method of mixing has not only an important bearing on the chemical, but also on the physical, nature of the mixture. The most valuable of the compounds, and one which is easily modified in the mixing, is a bluish, gelatinous r>recipitate having about the same specific gravity as the fluid in which it is suspended. In mixing the Bordeaux by the different methods used by the orchardists the following gave the best results, and is the only one recom- mended : Sulphate of copper (blustone) 6 pounds Quick-lime 4 pounds Water 50 gallons To prepare 50 gallons of Bordeaux mixture, weigh out 6 Ibs. of bluestone and place it in a sack; suspend the sack from a stick laid across the top of a barrel, so that the bot- tom of the sack hangs clear of the bottom of the barrel. Pour in enough water to cover the bluestone. As soon as all the bluestone has dissolved take out the sack and add enough more water to make 25 gallons. Bluestone is readily dissolved in hot water and the use of this will facilitate rapid prepara- tion when work is rushing. Slake 4 Ibs. of good quick-lime in a barrel, taking care to do it in such manner that when the lime is all slaked the mass will be a smooth paste, free from small particles of unslaked or burned lime. In order to get A Bulletin on Orchard Practice 23 the best results great care must be taken. After placing the lime in the barrel, add enough water to wet it thoroughly, and when the lime begins to dry and crumble add more water, be- ing careful not to add enough to chill it. By pouring on a sufficient amount of water to keep the lime from burning a smooth paste is formed, free from grit and small lumps, pro- vided a good quality of lime has been used. Having slaked the lime, add enough water to bring the mass up to 25 gallons. Stir the lime thoroughly through the water and it is tjien ready for mixing with the blustone solution. Two men are required to do this mixing properly. The solutions of lime and bluestone should be poured together slowly, and in such a manner that the solutions will mix in falling. When mixed, stir thoroughly, using a wide, wooden paddle. After strain- ing, the mixture is ready for use. There is some danger of not having sufficient lime to unite chemicallv with all the bluestone — it is best to test the mix- ture to see if sufficient lime has been used. Fill a saucer with the solution and add to it a few drops of a solution of ferro- cyanide of potash (one ounce to a half pint of water). If a brown color appears, add more lime paste to the mixture, stir in thoroughly and test a second time. Add lime until the brown color does not appear when test is made. SULPHUR LIME FORMULA. Lime 1 pound Sulphur 1 pound Water 3 or 4 gallons First slake the lime, using only enough water to keep it moist so it will all dissolve and not burn. Reduce to a thick paste, then add enough water to make a thin liquid. Put in the sulphur, stir it thoroughly before cooking and occasion- ally while cooking. If the cooking vat is large enough all the water can be added at first, but if not it can be put in later. To boil constantly for one hour is enough, as it is claimed it can be cooked too long. When the sulphur is all dissolved the liquid will be of an amber color. It should be poured into 24 A Bulletin on Orchard Practice the spraying tank through a strainer to remove the residue that would clog the nozzle. It is a common mistake to use too much lime in the prep- aration of the sulphur-lime solution. Too much lime de- stroys the caustic properties of the sulphur and renders the spray less effective. It is best to use this preparation while fresh, or nearly so, and according to the above formula. F. A. H. KEROSENE EMULSION. Kerosene 2 gallons Whale-oil Soap (or 1 qt. soft soap) ... % pound Water 1 gallon Dissolve the soap in the water by boiling, and pour this boiling hot into the kerosene, away from the fire. The mix- ture is then to be agitated violently, preferably by pumping it back on itself with a force pump. After a few minutes the mixture becomes creamy in consistency. If well made, the emulsion will stand for a long time without free oil rising to the surface. Unless otherwise stated, use 1 gallon of the emulsion to 15 to 20 gallons of water in spraying. PARIS GREEN. Paris Green 1 pound Good Lime 1 pound Water 125 gallons Slake the lime in a little water and then mix in the Paris green to form a thin paste. Strain the paste into the water so as to remove all lumps. See article on the Codling Moth for Arsenate of Lead formula, the most modern of the poisonous sprays. YR ID 320942 UNIVERSITY OF CALIFORNIA LIBRARY