Chapter 25

My first one was built underground with pipes for ice and salt to cool it, something like the system that I am now using. But I found out in the first season that it takes a great deal of ice to offset the heat that is coming in from the ground at the sides and bottom of the cellar. And so I built the storage which I am now using entirely above ground, using the basement under it for storing cabbage and vegetables. I built this in 1913, the size 28x56 feet, using cement blocks for the basement, where the cabbages are stored. The cold storage above this is built as follows:

First, an ordinary frame building with 2x4 inch studdings sheathed on the outside with drop siding with No. 3 flooring. Inside of this sheathing 2x4 inch studs placed flatwise, sheathed on the inside with No. 3 flooring, and the six-inch space back of the studs filled with sawdust. On the outside of this firing strips one-half foot are nailed, which are covered with linofelt. One-half foot firing strips are nailed inside of this, and these also covered with linofelt. To this again one-half foot firing strips are added, to which are nailed metal lath, and the whole is plastered with cement. The floor both above and below is made of 2×12 joists, with No. 3 flooring nailed below the joints, the space between which is then filled with ten inches of saw dust, leaving an air space of two inches at the upper edge of the joists. The joists are then covered with linofelt and then the linofelt covered with No. 3 flooring.

On the north and west sides I found it necessary to add one more waterproof coat of linofelt in order to make sure of keeping out the frost.

I have so far only finished up for cold storage one-half of the room, using the other half for a packing room, so that my present facilities are only 28×28 feet. This room is cooled by eight inch pipes of galvanized iron, extending from the attic above to troughs near the floor, that are sloping so as to carry off the melted ice. These pipes are on both sides about two feet apart. The ice is pulled up into the attic by horsepower and broken up small enough into pieces to feed the pipes. The amount of salt used with the ice depends upon how fast we want the ice to melt. A large quantity of salt cools the storage down quicker. In practice I find that it takes one hour for a man to elevate a ton of ice, chop it up and fill the pipes. They hold something over a ton and must be filled every other day in ordinary September weather. It will not do to let the pipes remain less than one-half full. When the ice gets down that far, we have to fill again.

The total cost of my storage when it is entirely furnished up and the present capacity doubled will be about $3,000.00. At present it holds 2,000 standard size apple boxes.

I find that it only pays to put in good fruit that in ordinary seasons will keep until the first of March and hold its flavor well and give good satisfaction on the market. Icing stops about the middle of November. The cost per box for storage is as follows: Ice and salt, ten cents. Interest on investment, six cents. I have figured out carefully the entire cost of growing and storing apples, and find out that leaving out the interest on the value of the land, it will approximate forty-eight cents per bushel. This includes cultivation, spraying, packing, and picking. The question which now interests me is whether we can grow fruit good enough and stand the expense and compete with apples grown in the other good fruit sections of the country.

Mr. Older: I had the pleasure of visiting this plant with Mr. Wedge, and this man had quite a good many boxes of as fine apples as you would wish to see. This was along the latter part of February, and they were in fine condition. He had a lot of Jonathans and Yankees and some other varieties I don't remember, grown on top-worked trees there.

The Plum Curculio.

EDWARD A. NELSON, UNIVERSITY FARM, ST. PAUL.

(Prize Winner at Gideon Memorial Contest.)

The small crescent-shaped punctures, so common on apples, plums, peaches and other fruits, are made by a small snout-beetle known as the plum curculio. The beetles issue from their winter quarters at about the time the trees are in full bloom and feed on the tender foliage, buds and blossoms. Later they attack the newly set fruit, cutting small circular holes through the skin in feeding, while the females, in the operation of egg-laying, make the crescentic cuts so characteristic of this species. The egg, deposited under the skin of the fruit, soon hatches into a very small whitish larva or grub, which makes its way into the flesh of the fruit. Here it feeds greedily and grows rapidly, becoming, in the course of two weeks, the fat, dirty white "worm" so well known among fruit growers.

The curculio is a native of North America and for more than 150 years has been known as an enemy of fruits. Our early horticultural literature abounds with reference to its depredations. In more recent times the great increase in planting of fruits, brought about to supply the increased demand, has permitted it to become much more abundant than formerly, and the plum curculio constitutes at the present time one of the most serious insect enemies of orchard fruits. Statistics gathered of its depredations show that it is distributed over much of the area of the United States. Its western limit is, roughly, a line drawn through the centers of North Dakota, South Dakota, Nebraska, Kansas, Oklahoma and Texas. East of this line the entire United States is infested except the southern third of Florida and the northern half of Maine.

Is the plum curculio causing much damage to the fruit growing industry of this country? That it is is shown by the National Conservation Committee in its report in Volume III, page 309, where it states that the average annual loss in late years to only three fruits is as follows:

Apples $3,257,806

Peaches 4,088,814

Plums 1,244,149 ---------- Grand Total $8,590,769

Just think of it! A total loss each year to only three fruits of over $8,500,000. This amount is a heavy drain upon the fruit growing industry of this country. During the past twenty-five or thirty years the total damage caused by this insect, to the various fruits which it attacks, would, on a conservative estimate, probably be not less than $100,000,000.

These figures show the absolute need of the adoption of effective remedial measures against this insect so as to lessen this loss. But before we can hope to combat this insect systematically and successfully it is necessary to know its life history and habits.

There are four distinct stages in its life cycle: (1) The egg, (2) the larva, or "worm," (3) the pupa, and (4) the adult, or beetle.

The curculio passes the winter in the adult stage under accumulations of partly decayed leaves, among the closely-packed dried grass of sod-covered orchards, and probably wherever suitable protection from the winter may be found. Its depredations are usually worse near woods, so it probably finds here very suitable places for wintering.

In the spring, when the fruit buds are unfolding, the beetles begin to emerge from their winter quarters and feed to some extent on the blossoms and tender leaves of the fruit trees. Mating soon begins, and by the time the fruit is well set the beetles make this fruit the chief object of their attention. The circular punctures in the skin are feeding punctures, while the crescent-shaped ones are egg-laying punctures. A single egg is deposited in a puncture, although several may be placed in a single fruit. From one to eight eggs may be deposited daily by an individual female, which may be continued for several months. The great majority of the eggs, however, are deposited by the end of eight weeks. These eggs hatch in from three to seven days, being influenced greatly by the weather.

The egg hatches into a larva, or "worm," which bores into the fruit. It becomes full-grown in from twelve to twenty days and bores out of the fruit. It enters the soil, burrows to a depth of one-half to two inches, and forms an earthern cell in which to pupate. In three or four weeks it emerges as a full grown beetle and attacks the ungathered fruit and the foliage. On the approach of cold weather the beetle seeks a protected place in which to pass the winter.

The character of the injury is very nearly alike in all fruits. In the plum the fruit often falls to the ground before mature. In seasons of short crops very little fruit may remain to ripen. The punctures cause the fruit to become mis-shaped and to exude masses of gum. The ripe fruit becomes "wormy." The late varieties may be seriously injured by the new generation of adults. In the apple the injury to the fruit is about the same as in the plum, except that the infested fruit is not so likely to fall to the ground and that the egg rarely hatches into the grub there. The fruit becomes knotted and pitted. The late varieties may also be injured by the new generation of adults. In the peach, cherry and other stone fruits, the injury closely resembles that of the plum.

Although the plum curculio has some natural enemies that tend to reduce its numbers somewhat, yet they are not important enough to be considered as effective means of control. Some of these natural enemies are parasites of various kinds, birds, chickens and the like.

There are several remedial measures practiced, varying in their degree of effectiveness. Away back in the early days of horticulture in this country, when the curculio became very abundant rewards were offered for an effective method of combating it. Several were proposed, but only a few were at all effective. The best of these methods is what is called "jarring."

The curculio has the habit of falling to the ground and "playing 'possum" when disturbed. This led to the practice of holding or spreading sheets beneath the tree and then striking the tree a sudden, forcible blow with a padded pole or mallet in order to dislodge the beetles. The trees were jarred daily from the time the calyx or "shuck" began to slip from the newly set fruit until the beetles had disappeared, or for at least four or five weeks. This was practiced to quite an extent, but it takes too much time and is too expensive.

A still better remedy is clean cultivation. Experiments have shown that as high as 76.75 per cent. of the pupae may be destroyed by means of thorough cultivation. The mere breaking of the pupal cell, leaving the earth in contact with the body of the pupa, is fatal to many. Others are killed by the crushing action of the earth as it is stirred. Others are exposed to the elements and subject to the attacks of their enemies, such as ants and birds. Sunlight is quickly fatal to them, and exposure to the air on a warm day in the shade is also fatal to them. Observations show that the insect is in the pupal condition in the ground in from fifty to sixty-five days after the falling of the blossoms of such fruit as apples and plums. Data have been presented to show that the minimum time spent in the ground is about twenty days. Shallow cultivation should begin, therefore, in about eight or nine weeks after blossoming. It is best to cultivate every week or oftener for six or seven weeks. It is very necessary that this cultivation should reach immediately beneath the spread of the limbs, as most of the curculios are found here, having dropped from the fruit above and burrowed into the soil where they fell.

The third method of combating the curculio, the method most commonly used and most generally recommended, is spraying with arsenical poisons. The spray most generally used is arsenate of lead. The most economical and effective way is to add arsenate of lead to Bordeaux mixture. The Bordeaux is mixed in the following proportions: three pounds of copper sulphate (blue vitriol), four pounds of lime, and fifty gallons of water. To this amount of Bordeaux mixture three pounds of arsenate of lead are added. In place of Bordeaux mixture lime-sulphur may be used. If the insecticide is used alone, three pounds of arsenate of lead in fifty gallons of water make an effective spray. It is best to spray three times, the first spraying coming just before the blossoms open, the second coming ten days later, and the third another ten days later. The cost is from ten to fifteen cents per tree for the three sprayings. This cost is lessened when combined with other sprays.

While spraying greatly reduces the injuries inflicted, yet it is apparent that account must be taken of other factors, such as the relative abundance of insects as compared with the amount of fruit present on the trees. With a small fruit crop and an abundance of curculios, the most thorough spraying in the world will not serve to bring through a satisfactory amount of sound fruit.

While spraying is undoubtedly the most important aid and, if persisted in from year to year, may answer for its control, as its effects are cumulative, yet it is clear that other control measures should also be employed. In all cases which have come under observation the insects have always been found most abundant in orchards which are in sod or are poorly cared for and allowed to grow up more or less in weeds and trash. Also, orchards near woods always suffer severely, especially along the border. As opposed to this condition is the notably less injury in orchards kept free from weeds and trash. In such cases spraying usually given for other insects, as the codling moth, serves to keep the curculio well under control. In fact, it may be said as a general statement that the curculio will never become seriously troublesome in orchards given the usual routine attention in cultivation, spraying and pruning now considered essential in successful fruit growing. Serious losses from the curculio are almost conclusive evidence of neglect, which is best and most quickly corrected by the adoption of proper orchard practice.

* * * * *

AN ANTIDOTE FOR WASP STINGS.--It not infrequently happens that persons biting unguardedly into fruit in which a wasp is concealed receive stings in the mouth or throat. Such stings may be exceedingly dangerous and even fatal since the affected tissues swell rapidly and this is liable to cause difficulty in swallowing and breathing. An effective antidote is employed in Switzerland. The sting is rubbed vigorously with garlic, or, if it is too deep in the throat for this treatment, a few drops of the juice from bruised garlic are swallowed. If garlic is not to be obtained onion may take its place, but is a less active agent. The efficacy of this simple remedy was verified by a Swiss specialist, who found it important enough to be presented at a session of the Vaudois Society of Medicine.

Increasing the Fertility of the Land.

PROF. F. J. ALWAY, DIVISION OF SOILS, UNIVERSITY FARM, ST. PAUL.

I have been asked to speak on "Increasing the Fertility of the Land." To speak on such a subject is sometimes a rather delicate matter because some people consider they have a soil so good that you can't increase its fertility. With some of the prairie soils, when they were first plowed up that wouldn't have been so very far amiss. Take those black prairie soils with the grayish yellow clay subsoil, with an abundance of lime in it, which you find in a large part of the state, including a large part of Hennepin County, and you have as good a soil as you may expect to find anywhere on the earth's surface. But you can't keep a soil up to its full limit of fertility, no matter how good it is, unless you frequently treat it with something.

When a soil is well supplied with lime there are three things that are liable to be deficient. If it is not well supplied with lime there may be four, but the bulk of your soils are good enough so far as lime is concerned. Those three are potash, which is abundant and will be abundant 100 years from now, phosphoric acid, or phosphorus, with which our soils are fairly well supplied, and nitrogen, which comes from the vegetable matter. In nitrogen our prairie soils are remarkably rich when first plowed up. The phosphoric acid and the potash you can not lose unless they are taken away in the form of crops, but the nitrogen may be lost without even taking off crops. All you have to do is to cultivate your soil, when part of the nitrogen becomes soluble in water and is carried down by the rain into the water-table unless you have plants growing with roots to take it up; a large part escapes into the air. So when your black prairie soil has been under cultivation for twenty years, as an orchard, usually from one-half to one-third of the original nitrogen has escaped, most of it into the air, only the smaller part being carried off in the crops. That is the one thing that orchardists and horticulturists have to concern themselves about first of all, so far as soil fertility is concerned.

I see that the first of the questions for me to answer deals with that. "What crop do you consider the best green manure?" There are two kinds of green manures. One is represented by rye. Rye takes up the nitrogen that is in the soil, and when it dies leaves behind what it took out of the soil; the next crop can get this. By plowing under the rye crop you do not increase the amount of nitrogen, the most important element of fertility in the soil.

We have a better green manure than that, better than rye or oats or barley or any of those plants that properly belong to the grass family; namely, the members of the clover, bean or pea family--all of these plants which are called legumes, which have pods and which have flowers shaped like butterflies.

As these grow they take up nitrogen from the air; the bacteria which make their home on the roots of those plants take the nitrogen from the air and give it to their host plants. The plants receive this nitrogen, store it in themselves, and when the crop is plowed under you have a great amount of nitrogen added to the soil. Now, a clover crop of an acre growing from spring until the freeze-up in the fall may take out of the air as much as 120 pounds of nitrogen. One hundred and twenty pounds of nitrogen, bought in the form of commercial fertilizer from Swift & Company, or Northrup, King & Company, would cost you $24.00. The clover has taken that much out of the air. If the crop were pastured off, the greater part of this nitrogen would be returned to the soil; when you plow the clover under still more nitrogen is taken from the air by bacteria that live upon the decaying plant material, and you may have $48.00 worth of nitrogen per acre added to the soil by simply growing clover for one year.

Any kind of green manure crop that bears pods is good. Vetches are good, and soy beans are among the best for orchards. Clover, if you give it time to make a good growth, is as good as anything.

The next question is--"Should apple raisers use commercial fertilizers?" Now, the apple tree, when it is growing on good soil, makes such a vigorous root development that it is hard to get any commercial fertilizer to help it. On poor soils it, like any other kind of plant, will respond to fertilizers. Some of the eastern experimental stations have been carrying on investigations with commercial fertilizers for a great many years to see whether in apple orchards these will cause an increase in the yield or an improvement in the quality of the fruit. On good soils, even after ten or twelve years' fertilization they have been found to have no effect except in the case of nitrogen, and this can be better supplied in the form of a green manure plowed under than in any other way. That is to say, keep your orchard clean until the last of July or first of August, sow your green manure crop, let it grow until freeze-up and stay there during the winter time. It holds the snow and so affords some winter protection. In the spring plow it under, and you plow under all the nitrogen that the plants had collected the previous year. Then keep your orchard clean during the summer time, until in July or August you again sow the green manure crop.

The fertilizers that I get more inquiries about than any others are the phosphates--bone meal, acid phosphate and rock phosphate. Horticulturists have read that striking results are being obtained with these on certain crops in the eastern and central states, and they want to know whether the same fertilizers will pay here. Some inquire about potash fertilizers. With the latter there is no doubt but that the results we would obtain would, even under ordinary circumstances, not pay. At the present time potash costs about ten times what it does in times of peace. Sulphate of potash, which ordinarily brings $45.00 per ton, is now quoted at $450. This puts its use out of the question.

The phosphoric acid fertilizers are no higher now than usual. They cost, according to the kind, from $9.50 to $25.00 per ton. Some of them are produced near here--in South St. Paul. With tree crops, apple, plum and pear, we need expect no increased yield from the use of phosphates, unless it be on our very poorest soils. On certain crops, like the bush fruits--the currants and the raspberries, we might get a distinct benefit. I cannot give a definite answer to that. I can tell you what results they have obtained in New York state, what they have obtained in Pennsylvania or Illinois or Maine, but what results we would get in Minnesota we do not know. We can't apply their results to our conditions. The only thing we can do is to carry on such experiments here, and they have not yet been started. That brings me to a third question I have here.

"What experiments are being conducted by the University of Minnesota with orchard and other horticultural crops?" We realized the importance of this matter and plans were prepared. Then, as you know the last legislature was economical. It decided that one of the best places to make a cut would be in the funds for experimental work; when these funds were reduced we not only could start no new experiments but even had to cut off some of the old ones. For that reason these fertilizer experiments have to wait until the next legislature or the one after. I hope the next legislature will make such an appropriation that they may be begun.

Now, for the next question. A man states that he can secure at a very low rate limestone from one of the Minneapolis companies producing crushed limestone for road-making purposes and wants to know whether it will pay him to haul it to his farm. Well, if you do not have any other work for your teams it may pay you. However, if your time is valuable, you had better take some samples of the soil and send them in to the experiment station. Just address them to the Soils Department or Soils Division. Then we can decide whether it is worth while trying some of the limestone. We cannot tell you whether it will pay; we can tell you whether it is likely to pay, or whether it is likely to be a waste of energy, or whether it is so doubtful that you ought to give it a fair trial. On perhaps two-thirds of the fields in Hennepin County it would be a waste of money and energy; on about half of the others, we may say, it is almost certain to be a good investment at a dollar a ton. On the remaining portion we simply can't say. On these, chances are even whether it would pay. No crops are injured by limestone, so you are safe in putting it on. Practically all crops are benefited by it on sour soils and especially the vegetable crops.