Crops and Methods for Soil Improvement Part 3

A Clean Seed-bed.--Much failure with alfalfa is due to summer gra.s.ses and other weeds. The moisture in our eastern states favors plant-life, and most soils are thoroughly stocked with the seeds of a large number of weeds. The value of blue-gra.s.s and timothy would be comparatively small if they were not capable of monopolizing the ground when well started and given fertility. Alfalfa plants are less capable of crowding out other plants, and especially in their first season. Their habit of growth is unlike that of gra.s.s. Rational treatment of alfalfa demands that the surface soil be made fairly clean of weed seed, and this applies with peculiar force to annual gra.s.ses, like fox-tail. If attention were paid to this point, failures would be far less numerous.

Old gra.s.s land should not be seeded until a cultivated crop has followed the plowing. The land should be in good tilth, and capable of producing a good crop of any sort. Alfalfa is not a plant for poor land, although it does add organic matter and nitrogen.

Varieties.--There is only one variety of alfalfa in common use in this country, and the western-grown seed sold upon the market is known simply as alfalfa. Bound up in this one so-called variety are many strains differing in habit of growth, and their differentiation will occur, just as it has in the case of wheat, and is now proceeding slowly with timothy. The eastern grower at present should use the variety of the west that is furnishing nearly all the seed produced in this country. There is a variety known as Sand Lucerne that has shown value for the light, sandy soils of Michigan. The Turkestan variety was introduced for dry, cold regions, but does not produce much seed.

Clean Seed.--Care should be exercised to secure seed free from impurities. If one is not a competent judge, he should send a sample to his state experiment station for examination. The practice of adulteration is decreasing, but the seed may have been taken from land infested with pernicious weeds.

The impurity most to be feared is dodder. There are several varieties, the seeds varying in size and color. The same pest may be found in clover fields, but the injury is less because the clover stands only two years. The dodder seed germinates in the soil, and the plant attaches itself to the alfalfa, losing its connection with the soil and forming a ma.s.s of very fine vines that reach out to other alfalfa plants. In this way it spreads, feeding on the sap of the host plants and killing them.

When the infestation is in only a few spots in the field, the remedy is to cover with straw, soak with kerosene oil, and burn. All the infestation at the edges of these spots must be destroyed.

When the dodder is too widely distributed throughout the field to permit of this treatment, the only course is to plow the field at once, and to grow cultivated crops for two or three years. It is believed that no variety of dodder produces seed freely in the eastern states, and that the hay made from the first crop of alfalfa or red clover will not contain any seed of this pernicious plant.

The Seeding.--When alfalfa has become established on eastern farms, the difficulties in making new seedings will be smaller. The experience of growers will save from mistakes in selection of soils and preparation of the ground, and the thorough inoculation with the right bacteria that can come only with time will do much to insure success. The unwisdom of making seedings in ground filled with gra.s.s and other weed seeds will be appreciated. It is quite probable that much successful seeding will be made in wheat and oats, where the alfalfa is to stand only one or two years. These practices are not for the beginner. His land is not thoroughly supplied with bacteria, and every chance should be given the alfalfa.

If there are no annual gra.s.ses, such as appear so freely in some regions in mid-summer, spring seeding is excellent. A cover crop is then desirable, and nothing is better for this purpose than barley at the rate of 4 pecks of seed per acre. In all experimental work 25 pounds of bright, plump alfalfa seed per acre should be sown. The seeding should be made as soon as spring comes, the barley being drilled in, and the seed-spouts of the drill thrown forward so that the alfalfa will fall ahead of the hoes and be covered by them.

Seeding in August.--Much land is infested with annual gra.s.ses and other weeds, and in such case seedings should be made in August, as described in Chapter VIII.

Subsequent Treatment.--If the alfalfa plants find the bacteria at hand, they will begin to profit from them within the first month of their lives. A large percentage of the plants may fail to obtain this aid in land which has not previously grown alfalfa, and within a few months they indicate the failure by their light color, while the plants liberally supplied with nitrogen through bacteria become dark green.

Where there are no bacteria, the plants turn yellow and die.

There are diseases that attack alfalfa, causing the leaves to turn yellow, and when they appear, the only known treatment of value is to clip the plants with a mower without delay. The next growth may not show any mark of the diseases.

[Ill.u.s.tration: Curing alfalfa at the Pennsylvania Experiment Station.]

When alfalfa is seeded in the spring on rich land, a hay crop may be taken off the same season. If the plants do not make a strong growth, they should be clipped, and the tops should be left as a mulch. The clipping and all future harvestings are made when the stalks start buds from their sides near the ground. This ordinarily occurs about the time some flowers show, and is the warning that the old top should be cut off, no matter how small and unprofitable for harvesting it may be. The exception to this rule is found only in the fall. An August seeding may make such growth in a warm and late autumn that flowering will occur, and lateral buds start, but the growth should not be clipped unless there remains time to secure a new growth large enough to afford winter protection. This is likewise true of a late growth in an old alfalfa field.

Owners of soils that are not well adapted to the alfalfa plant will find top-dressing with manure helpful to alfalfa fields when made in the fall. The severity of winters in a moist climate is responsible for some failures. If the soil is not porous, heaving will occur. A dressing of manure, given late in the fall, and preferably during the first hard freeze, will prevent alternate thawings and freezings in some degree. The manure should have been made from feed containing no seeds of annual gra.s.ses or other weed pests.

Rolling in the spring does not serve to settle heaved alfalfa plants.

The tap-roots are long, and when they have been lifted by action of frost, they cannot be driven back into place.

It is believed that the permanence of an alfalfa seeding may be increased by the use of mineral fertilizers in the early spring. In the case of one alfalfa field of fifteen years' standing in the east, the fertilizers were applied immediately after the first hay crop of the year was removed. Three hundred and fifty pounds of acid phosphate and 50 pounds of muriate of potash per acre is the mixture recommended.

When old alfalfa plants do not stand thickly enough on the ground, gra.s.ses and other weeds come in readily. They can be kept under partial control by use of a spring-tooth harrow, the points being made narrow so that no ridging will occur. The harrow should be used immediately after the harvest, and will not injure the alfalfa.

It does not pay to use alfalfa for pasturage in our eastern states because the practice shortens the life of the seeding.

Alfalfa makes a seed crop in profitable amount only in our semi-arid regions. No attempt to produce a seed crop in the east should be made.

CHAPTER VII

GRa.s.s SODS

Value of Sods.--The character of the sods is a faithful index of the condition of the soil in any region adapted to gra.s.s. The value of heavy sods to a soil cannot be overestimated. They not only give to a farm a prosperous appearance, but our country's agriculture would be on a much safer basis if heavy coverings of gra.s.s were more universal. We do not hold the legumes in too high esteem, but the emphasis placed upon their ability to appropriate nitrogen from the air has caused some land-owners to fail in appreciation of the aid to soil fertility that may be rendered by the gra.s.ses. One often hears the statement that they can add nothing to the soil, and this is serious error. They add all that may be given in the clovers, excepting nitrogen only, and that is only one element of plant-food, important though it be. A great part of the value of clover lies in its ability to supply organic matter to the soil and to improve physical condition by its net-work of roots. Heavy gra.s.s sods furnish a vast amount of organic matter which not only supplies available plant-food to succeeding crops, but in its decay affects the availability of some part of the stores of potential fertility in the land.

[Ill.u.s.tration: A Heavy Gra.s.s Sod in New York.]

Prejudice against Timothy.--Timothy, among the gra.s.ses, is especially in disrepute as a soil-builder, and yet its value is great. The belief that timothy is hard on land is based upon observation of bad treatment of this gra.s.s. There is a common custom of seeding land down to timothy when it ceases to have sufficient available plant-food for a profitable tilled crop, and usually this is the third year after a sod has been broken. The seeding is made with a grain crop that needs all the commercial fertilizer that may chance to be used. Clover may be seeded also, and on a majority of farms it fails to thrive when sown. If clover does grow, the succeeding crop of timothy may be heavy. If clover does not grow, the timothy is not so heavy. The seeding to gra.s.s is made partly because a tilled crop would not pay, and partly because a hay crop is needed. It comes in where other crops cannot come with profit, and it produces fairly well, or very well, the first year it occupies the ground by itself. With little or no aid from manure or commercial fertilizer, it adds much to the supply of organic matter in the soil, and it produces a hay crop that may be made into manure or converted into cash.

If the sod were broken the following spring, giving to the soil all the after-math and the ma.s.s of roots, its reputation with us would be far better than it is. This would be true even if it had received little fertilizer when seeded or during its existence as a sod, not taking into account any manure spread upon it during the winter previous to its breaking for corn. But the rule is not to break a gra.s.s sod when it is fairly heavy. The years of mowing are arranged in the crop-rotation to provide for as many harvests as promise immediate profit. On some land this is two years, and not infrequently it is three. Where farms are difficult of tillage, it is a common practice to let timothy stand until the sod is so thin that the yield of hay is hardly worth the cost of harvesting. Then the thin remnant of sod is broken for corn or other grain, and the poor physical condition of the soil and the low state of available fertility lead to the a.s.sertion that timothy is hard on the soil. This is a fair statement of the treatment of this plant on most farms.

Object of Sods.--The land's share of its products cannot be disregarded without loss. The legumes and gra.s.ses come into the crop-rotation primarily to raise the percentage of organic matter that the land may appropriate to itself within the rotation. Some of the crops usually are for sale from the farm. Most of the crops require tillage, and that is exhaustive of the store of humus. A portion of the time within the rotation belongs to a crop that increases the supply of vegetable matter, unless manure is brought from an outside source. Sods lend themselves well to this purpose because they afford some income, in pasturage or hay, while filling the soil with vegetation. The tendency is to forget the primary purpose of sods in the scheme, and to ignore the requirement of land respecting a due share of what it produces.

Attention centers upon the product that may be removed. The portion of the farm reduced in productive power for the moment goes to gra.s.s, while the labor and fertilizers are concentrated upon the fields that are broken for grain and vegetables. The removal of all the crop at harvest, and probably the pasturing of after-math, are the only matters of interest that the fields, depleted by cultivation and seeded down to gra.s.s, have for the owner until the poor hay yield and the need of a sod for corn draw attention again to them.

Seeding with Small Grain.--The usual custom is to sow gra.s.ses with small grain, and there is much to commend it. The cost of preparing the seed-bed rests upon the grain crop, and the conditions are favorable to fall growth and winter protection, if the seeding is made in the fall.

Wheat and rye are good crops with which to seed. In the case of fertile land there is the danger that the timothy will establish itself too well in a warm, moist autumn to permit clover to get a foothold the following spring, and clover should always be seeded for the sake of fertility. In northern lat.i.tudes clover cannot be seeded successfully as late in the season as wheat should be sown, as it fails to become well rooted for winter. The overcrowding of clover by timothy is met in part by reduction in amount of timothy seed sown with the wheat.

The oat crop is less satisfactory for seedings to gra.s.s and clover. The leaves near the ground are too thick, shading the young plants unduly, and the late harvest exposes the gra.s.s and clover when the season is hot, and usually dry. Some reduction in the amount of seed oats used per acre helps to save from injury.

Seeding in Rye.--When thin land is desired for pasture, and available fertility cannot well be applied, a sod may be formed more surely by seeding with rye, using the rye for pasture and a mulch, than, probably, in any other way. The ground should have good tillage and then be seeded to rye in September at the rate of six pecks of seed per acre. Timothy and red-top should be seeded with it, and in the spring red and alsike clover should be added. Whenever the ground is dry enough in the spring to permit the tramping of cattle without injury, the rye should be pastured, and preferably by a sufficient number of animals to hold the rye well in check. When the usual time for heading comes, all stock should be removed, and when heads do appear, the growth should be clipped with a mower and left as a mulch on the surface. A second clipping will be required later, with cutter-bar tilted well upward. When the usual summer drouth is past, livestock can again be turned into the field. This method is suggested only for thin fields that have failed to make catches of gra.s.s, and that for some reason cannot well be given the fertility that all thin soils need. The application of lime before seeding to the rye is an expense that usually must be met in the case of such fields, and fertilizers should be used.

Good Soil Conditions.--When the gra.s.ses and clovers desired for a sod are sown with small grain, there is compet.i.tion between them and the grain crop for fertility, moisture, and light. The grain crop is the one that will produce the income the following summer, and naturally is given right of way. The amount of seed is used that experience teaches is best for a maximum yield of grain. Usually this gives a thicker stand of plants than is best for the tiny gra.s.s and clover plants that often are struggling for existence down under the taller grain. If the farmer could see his way clear to cut down the quant.i.ty of seed wheat or oats used on a fertile soil, the catch of gra.s.s would be better, but the small-grain crop is not very profitable at the best, and the owner does not like deliberately to limit it.

A greater amount of failure is due to an inadequate supply of fertility. The gra.s.s does not suffer so much from over-shading as it does from starvation, both during the growth of the grain and after harvest. The stronger grain plants appropriate the scanty stock of available fertility, and leave the gra.s.s and clover nearly helpless.

This condition is especially noticeable in dry seasons when there is less opportunity to obtain food in solution. Plants which are expected in another season to fill the ground with vegetable matter are starved in the beginning and die. Plant-food is needed, and should be mixed with the soil when the seeding is made. The fertilizer needs are discussed in another chapter.

When manure is available, it should be spread on the plowed ground and mixed with the surface soil. If a soil is thin, or heavy, or light, the use of a ton of manure in this way can bring greater returns than under any other circ.u.mstances in general farming. It supplies some fertility, and it puts the surface soil into good physical condition for young plants. Land deficient in humus forms a crust after a rain, and a tiny plant suffers. A light dressing of manure, well mixed with the soil, tends to prevent this hardening of the surface and loss of water. There is no other form of fertility that can fully replace manure, for either compact or leachy land.

The probable need of lime has been discussed in other chapters. Clovers and the gra.s.ses want an alkaline soil, and there is waste of money and time in seeding acid land. The lime and the manure must not be mixed together in the air, but both can be used when fitting land for seeding, and both should be used if the need exists. One should be applied early and be well disked into the soil, and then the other application may be made and covered with the harrow. The soil is an absorbent, and the contact of manure and lime within the soil only leads to immediate availability, which is desirable in giving the gra.s.s a start.

CHAPTER VIII

GRa.s.s SODS--(_Continued_)

Seeding in Late Summer.--The natural time of beginning life, in the case of timothy, blue-gra.s.s, red-top, red clover, and alfalfa is in the summer or autumn. The best conditions of growth are given where no stronger plants take the plant-food and moisture. Wherever there is any difficulty in getting heavy gra.s.s and clover sods after the lime deficiency has been met, and wherever a hay crop has more value than a small-grain crop, the method of seeding alone in August should be employed. In warmer lat.i.tudes the date may be a little later, but in the northern states it should be in the first half of August for best results. Seeding alone offers opportunity to make conditions right for the seeds which are to be used, and in view of the importance of heavy sods to our agriculture, this reason alone is sufficient. In some regions the ability to subst.i.tute a good hay crop for a cereal that brings small net income is an item of value, adding to the proportion of feeding-stuff produced in the rotation and to the resulting supply of manure. The practice of making seedings to gra.s.s and clover alone is growing, and it is based on sound reasoning.

Crops that may Precede.--Farms that are under common crop-rotations may adopt the practice of August seeding. The winter wheat comes off in time for preparation, and this is true of an early variety of oats, and of rye and barley. Early crops of vegetables get out of the way nicely.

There is a vast total area of thin soil that may be brought up to a productive stage rapidly by the growth of a green-manuring crop to precede the gra.s.s and clover. Rye may be sown in the fall and plowed down in May, and cowpeas planted to be disked into the soil. Oats and Canada peas add organic matter with nitrogen when plowed down. The summer fallow, which deservedly has fallen into general disuse, may well be employed when a soil is in an inert state, provided gra.s.s and clover be permitted to appropriate the plant-food made soluble by the fallowing. The catch crops add organic matter while cleansing the land of weeds; the fallowing releases plant-food and is peculiarly efficient in killing out weeds.

Care must be exercised about preserving moisture in the ground, and therefore a green crop should not be plowed under immediately before seeding time. When a soil is thin, there may be no better preparatory crop than the cowpea, which will not make too rank a growth in the north to prevent its handling with a weighted disk harrow. By this means the soil below is left firm, and the rich vines are mixed with the surface soil, where most needed. It is always a mistake to bury fertility in the bottom of the furrow when a soil is thin and small seeds are to be sown. The infertile ground lying next the subsoil is not what is needed at the surface when preparing for a sod.

It is a good practice to use the early summer in making conditions better for an August seeding, if the land has fallen below a profitable state of productiveness. A growth may be plowed down in time for firming the seed-bed, or it may be cut into the surface soil with a harrow, or the time may be used in freeing inert plant-food and destroying weed seed. On better soils, and in warm lat.i.tudes, a crop for hay may be removed, especially in the case of the cowpea in the south, and the stubble prepared for seeding by use of the cutaway or disk harrow.

Preparation.--A seed-bed for small seeds planted in mid-summer must be able to retain moisture. Nothing robs a soil of water more surely than a breaking-plow. Its use is a necessity in farming, but this effect of plowing must be borne in mind when a seeding is planned for the driest period of the year. It goes without saying that sods should not be formed on land that is too solid for admission of air. A thorough plowing is needed by most soils prior to making a sod that will prevent further stirring of the ground for a long period of time. It is best when this plowing can be given in the preceding spring. This enables the ground to become firm enough to hold moisture. If there is time for a tilled crop, the cultivation is helpful. When the land must be broken in the summer, the plowing should be done several weeks before the seeding to gra.s.s must be made. The roller should follow the plow closely to destroy the s.p.a.ces that lie open to the hot air, permitting the land to dry out. All deep harrowings should be given soon after the plowing, stirring and mixing the ground, and then leaving it to settle so that moisture can be held. It is bad practice to continue deep harrowing until the seeding time of any small grain or gra.s.s planted in a dry part of the year. Firmness is wanted in the soil.

The Weed Seed.--The seeds of tilled crops are planted in ground containing much weed seed, and no harm may result. The cultivation needed to keep the soil loose, or to prevent evaporation, destroys the weeds. Gra.s.s, clover, alfalfa, and like seeds are put into the ground to occupy it to the exclusion of other plants for several years, as a rule, and no tillage can be given. The rule is to sow such seeds after tilled crops have been grown, and some weed seed has been destroyed, but there is evidence on every hand that the weed seed remains in abundance. Summer preparation for gra.s.s gives opportunity to destroy a great part of the seeds in the surface of the ground, and it is only when they are near the surface that the seeds of most weeds will germinate. Deep harrowings, continued up to time of planting, not only rob land of water, but they bring to the surface new lots of seed that had been safely buried, and become a part of the actual seeding when the gra.s.s, clover, or alfalfa is sown. The obviously right method of preparing for planting is to use only a surface harrow for a few weeks previous to seeding time, stirring the ground after every rain to the depth of three inches, or near that, and destroying the plants soon after germination of the seed. The process which is right for holding moisture is right for cleansing the ground.

Summer Gra.s.ses.--One of the worst pests is the annual gra.s.ses, springing up in June, July, and August. They are responsible for many failures to obtain stands of alfalfa, clover, and the valuable gra.s.ses.

The delay in seeding until August is due largely to this pest. When seedings are made in the spring, or in June, failure is invited where these gra.s.ses have a fast hold. The only effective way of combating them is to make the ground firm enough to encourage germination, and to stir the surface whenever a growth starts. The late seeding is the one means of escape, and if there is fertility and moisture, the newly seeded crop becomes well rooted by winter and takes the ground so completely that there is little room for weeds to start the next year.