The Book of Alfalfa: History, Cultivation and Merits / Its Uses as a Forage and Fertilizer

The most notable enemies of alfalfa are weeds, insects, parasites, and animals. More failures to raise alfalfa are caused by weeds than by all other enemies combined. The cause of weeds in a field is usually poor farming. Clipping alfalfa early in May will kill many weeds. If the weeds grow up, clip again and do the same every time they threaten to become rampant. If they are kept from seeding, and do not in a large measure crowd out the alfalfa, good crops may be had from it the second season. If sowed in the fall, disking early in April may kill most of the weeds. It is folly to sow alfalfa on a foul field, as it is far less expensive to kill out the weeds beforehand. Disking and clipping will do much to destroy them, but if they secure a strong foothold the best thing to do is to plow up the field, plant it in corn, give it clean cultivation, and sow alfalfa again when the weeds have been exterminated.

DODDER

Dodder is an annoying enemy. It is a parasite, belonging to the morning-glory family, growing from its own small seed but attaching itself very soon to the alfalfa stalk. It then separates itself from its own root and thereafter lives on the juices of the alfalfa until it ripens its seeds or has killed the alfalfa. The wisest and safest thing to do is to sow only seed so thoroughly cleaned that there will be no dodder with it. If, later, it is found that any dodder seed escaped the cleaning operations and is growing, the grower should go through the field with a knife or sickle and a large basket or sack and cut out and burn every dodder vine and every plant to which dodder is attached. If so unfortunate as to have sown seed with a considerable mixture of dodder, clip the alfalfa early in May, let the clippings dry for two or three days or longer, and then burn on the field, watching carefully to have the fire touch every part. It will facilitate a complete burning to sprinkle parts not burning readily, with kerosene. If there is a poor stand of alfalfa, largely infested with dodder, safety lies in plowing it up and cultivating the field in corn or potatoes for two or three years.

From an excellent article on the dodder that infests alfalfa (Cuscuta epithymum) by Mr. F. E. Dawley, a New York authority on alfalfa, and printed with illustrations in the Country Gentleman, the excerpts here following are taken:

“The only sure method of keeping alfalfa fields free from dodder is through exercising greater caution in the purchase of seed. There is no reason why thoroughly recleaned alfalfa seed should have any dodder seed in it, as reference to the illustrations will show. The relative sizes and forms of the seeds of alfalfa and dodder are shown herewith. It will be seen that there is a marked difference in both the sizes and the shapes of the seeds. The alfalfa seed is shaped like a little kidney bean, and varies in color from light yellowish-green to a rich golden-yellow, and in some instances, because of weathering, or sweating in the cock, or perhaps standing too long, it shows a reddish-brown color. The dodder seed is darker in color than the alfalfa, all of that which I have succeeded in gathering from the plants being a rich golden-brown. The accompanying illustrations show the form of the dodder and alfalfa seed respectively.

“The seeds, being sown, germinate in the soil, throwing up a slender, thread-like stem somewhat resembling a corn silk, which retains its connection with the ground until it comes in contact with the stem of the alfalfa plant. It twines around this tightly, sending its feeding suckers through the outside bark, and as soon as it is firmly attached to the host plant, the ground connection is severed and it is sustained by the plant juices which are taken in by the suckers. It continues to grow and spread, twining around other stalks and increasing very rapidly until a colony is established. Continuing to grow, it climbs toward the upper portion of the plants, feeding on their juices and sapping their vitality, but never goes to the extreme top, seeming to prefer the dampness and darkness of the matted alfalfa rather than sunlight. The plants first attacked begin to die, and the dodder, spreading out in all directions, forms a circle or ring.

“The rapidity with which the pest spreads makes it a serious menace to the alfalfa grower. Comparatively little work has been done by scientific men in studying the dodders and methods of eradication, and the fact that the little rootlets or suckers (haustoria) become so firmly affixed to the host plant that it must be destroyed together with the parasite, has made the work hard and the results obtained unsatisfactory. There are a number of methods by which dodder may be spread through a field. As soon as it becomes thoroughly established on a host plant, the many little branches, waving about like the shoot produced from the seed, attach themselves to other plants, and thus the colony is increased in size. In legumes, the host plant first attacked soon dies, but before this occurs, the parasite has become firmly established on adjoining plants and is reaching out and completing the colony. As soon as a host dies, the dodder also perishes, but before this happens it is very likely to have blossomed and seeded.

“In the operations of mowing, tedding, raking and drawing the alfalfa hay, these little colonies are spread about the fields by the machines and the workmen, and on the horses’ feet. The sale of infested hay is a prolific means of dissemination. Hunters and pleasure seekers, walking through the fields, notice the peculiar corn-silk-like growths and often, by picking up particles of it which are soon cast away, establish new colonies. The flower is very peculiar and attracts the attention of people passing, who are apt to pick them together with some of the maturing seed, and scatter these over the fields. In a pastured field, the animals spread the seed to some extent while moving from place to place in feeding. The most serious menace, however, is from the purchase of impure seed; farmers should always be absolutely certain that the alfalfa seed which they are buying is thoroughly recleaned and that no small weed seed is to be found in it. One should never sow clover or alfalfa from a field or even from a locality in which dodder is known to exist. It is probable that the seeds thoroughly ripened will retain their germinating powers for some years. The purchase of hay from dodder infested fields, or the purchase of manure from barns where infested hay has been fed, are sure sources of contamination.

“Where a newly seeded alfalfa field shows evidence of quite general dodder infection, it is useless to attempt to eradicate it, and the field should be plowed up and planted with some hoed crop for a period of years. Old fields that have been thoroughly infested will probably be more economically treated in this manner than in any other. In newly sown fields, one of the most effective methods is probably hoeing over the spots where the dodder appears, going over them once in two weeks and allowing nothing to grow on them until the dodder seed is germinated. A modification of this method has been used successfully by spading in fields where the colonies of dodder were seen, raking out all the tops, roots and branches, adding a little straw or hay and burning the mass, and then keeping the spot thoroughly hoed for a season. For fields where the colonies are small and scattered, this method of hoeing and shallow cultivation is probably the most practicable, as it helps to secure the early germination of any seeds that were left in the ground, and also kills them as soon as they are germinated. If the seed has developed, one must be careful not to spade it in too deep, as it may retain its vitality for some years if left covered in the moist soil.

“Burning has been recommended by some, raking the dodder vines and what is left of the alfalfa to the center of the colonies, putting brush or straw with it, together with some fine, light wood or chips and sprinkling with kerosene, so that the alfalfa plants will be burned close to the ground. This is necessary from the fact that the little coils of dodder close to the crown of the plants will retain their vitality and grow after a very severe burning, providing the alfalfa which is above the ground is not killed also. The most difficult problem to be confronted in killing out dodder where it has become established, arises from the fact that if these little coils which wind themselves closely around the plant are not killed or removed, the dodder will spread from these and make a new growth. Many experiments have been made with chemicals, but none of them have proved wholly successful, from the fact that these little rings were not destroyed. All the rest of the plant was killed and the production of flowers and seed prevented; but as these little rings were not killed, the dodder began growing again and continued to grow throughout the season.”

LEAF SPOT

Leaf spot is a very peculiar disease and, fortunately, not common in this country. It has been known in France since 1832. In 1891 it was destructive in Iowa alfalfa, the loss in the neighborhood of the experiment station being estimated at 50 per cent. In reference to this infliction the Iowa station, among other information, printed the following:

“Any time after the plant has attained a growth of four to six inches from the seed, but most commonly after the first year’s growth, there appears upon the upper side of the leaves small, irregular brownish spots, which enlarge to about one-sixteenth of an inch in diameter and extend through the leaf to the under side, turning all parts brown. When many spots occur on the same leaf the whole leaf soon turns yellow and falls off. This falling of the leaves and the natural loss in vigor, due to the diseased condition before the falling, constitute its great damage. Frequent cutting of the crop materially prevents the disease.”

In eastern states farmers report that there are frequent patches in their fields where the leaves turn red and the plant dies. The probable explanation of this trouble is “wet feet,” which alfalfa will not abide. Don’t expect to get a crop of alfalfa from a field in which water is near the surface. Drain it or use another field.

ROOT ROT

A disease peculiar to portions of the southern states is called “root rot,” and similar to the root rot found in cotton fields. The alfalfa dies in spots, these spots widening in circular form. This is a fungus that spreads only in summer. The only means of eradicating so far (reported by the Texas station) is the application of common salt and kerosene. It has not proven a serious annoyance.

GOPHERS AND PRAIRIE DOGS

Gophers and prairie dogs are great pests in some parts of the Middle West, and about the only successful means of combating them is poison. The state of Kansas has, probably more than any other, made a systematic effort to destroy its gophers and prairie dogs, by liberal appropriations and a field agent to supervise the work to be carried out under provisions of law by local officials.

The injury done by the gophers consists chiefly in throwing up mounds of soil taken from the burrows and these greatly interfere with operating the mowing machine in harvesting. In the alfalfa fields there is also a noticeable thinning out of the plants, by reason of the cutting off of the roots. These root cuttings are stored in the burrows in considerable piles, and are used in cold weather by the gophers for food. It is claimed by some alfalfa growers that this process of thinning out the plants is a benefit rather than an injury to the field, but, says Prof. D. E. Lantz, the official formerly in charge of the Kansas work, “I have known fields where this thinning has continued until the crop did not half cover the ground at cutting time, and the fields were plowed up for the planting of other crops. The loss from gopher depredations to the alfalfa growers of Kansas during 1901 was probably fully one-tenth of the entire product, and had a money value of at least $500,000.”

According to Professor Lantz, carbon bisulphide and other poisonous gases have frequently been recommended for the destruction of the pocket-gopher, but the great length of the burrows and their irregularities in depth prevent the gases from flowing into every part, and the animals often escape. Trapping, if properly done, is a sure method of killing the gopher; but it is attended with considerable labor and is very slow. An excellent trap for general use is the No. O ordinary steel trap. Sink it in loose soil to the level of the runway, nearly conceal it by sprinkling fine earth over it, and leave the hole open.

Gophers are easily poisoned. They are fond of potatoes, sweet potatoes, apples, raisins and prunes. The presence of strychnine, arsenic or other poisons does not seem to deter them from eating the food; but if the poison is sweetened they seem to eat it more readily. In summer it may be desirable to sweeten the poison, but in the fall and early spring it does not seem worth while. The poisoned food being introduced to the burrows below the surface, there is no danger of poisoning stock. It might be well, however, not to let swine run in the fields for a time after the poison has been put out.

The following method of introducing poison is recommended: Cut the potatoes or other food into pieces not more than three-fourths of an inch in diameter. Cut a slit in each piece and with a point of the knife blade insert a little sulphate of strychnine; as much as half the bulk of a grain of wheat. Having prepared the bait in sufficient quantity, go to the field armed with a round, sharp-pointed implement an inch or an inch and a half in diameter and of sufficient length. The tool here illustrated was made by a blacksmith.

It is a spade handle shod with an iron point. A bar is attached about fifteen inches from the point to enable the operator to use his foot in pressing it into the soil. With this tool it is only necessary to find the runway of the gopher. The handle is sufficiently thick to make a hole large enough to permit one to drop the poisoned potato directly into the burrow. The operator then passes on to another place, leaving the hole open. No digging with a spade or other hard labor is necessary. An experienced person can distribute poison to many acres of alfalfa in a day; and if proper care is taken to rightly distribute the bait, it will not be necessary to go over the ground a second time. Some experience is required to find the burrows quickly. It is best to insert the food as near as possible to the freshest mounds of earth. Two or three pieces of potato at that place are worth many scattered in other parts of the runway. The operator should avoid the larger mounds and those that are not freshly made.

For destroying prairie dogs, Professor Lantz says that out of thousands of suggestions nothing has been found more effective than strychnine poison and carbon bisulphide. Following are directions for preparing and using the strychnine:

“Dissolve one and a half ounces of strychnine sulphate in a quart of hot water. Add a quart of syrup—molasses, sorghum, or thick sugar and water—and a teaspoonful of oil of anise. Thoroughly heat and mix the liquid. While hot pour it over a bushel of clean wheat and mix completely. Then stir in two or more pounds of fine corn meal. The quantity of corn meal needed will depend upon the amount of extra moisture present. There should be enough to wet every grain of the wheat and no more. Care should be taken that there is no leakage from the vessel in which the wheat is mixed. Let the poisoned grain stand over night, and distribute it in the early morning of a bright day. Use a tablespoonful of the wheat to each hole occupied by prairie dogs, putting it near the mouth of the burrow in two or three little bunches. Do not put out the poison in cold or stormy weather. It will keep for a considerable time, and is much more effective after a cold period, as the animals are then hungry and eat the grain readily. A bushel of wheat should poison 1000 to 1200 holes. An excellent substitute for the oil of anise in this formula can be made by soaking two ounces of green coffee berries in the whites of three eggs. Let this stand for about twelve hours, and use the liquid instead of anise oil.”

A tablespoonful of carbon bisulphide, upon some such absorbent material as cotton, dry horse manure, or a piece of corn-cob, and rolled into the burrows, is effective. It is best immediately to cover the hole with a sod and stamp down firmly.

GRASSHOPPERS

Grasshoppers are a source of no little loss to alfalfa growers in some parts of the West. They usually do their greatest damage to the season’s second crop, the young not being very destructive to the first. The best remedy, or rather prevention, is deep disking in April and then harrowing to destroy the eggs.

Where the pests attack or are about to attack a field of alfalfa, Prof. L. Bruner, of the Nebraska station recommends the use of a “hopper dozer,” which is “simply a long, shallow pan of stove-pipe iron or galvanized iron mounted on runners and backed by a light frame covered with cloth. The pan is about four inches deep, from eighteen inches to two feet wide, and from ten to sixteen feet long. It is partly filled with water and a little kerosene. A horse drags the machine across the field over the stubble of the first crop and the half-grown hoppers jump into the pan where the oil coats them over and kills every one that it touches. The hopper dozer works best on level land. On sloping ground the oil and water run to one end and slop over. To prevent this the pan is usually divided into sections by a number of partitions. The runners should stick out in front of the pan about a foot and one-half, and a piece of chain or heavy rope should be stretched loosely between them to drag ahead of the machine and make the hoppers jump. On level fields there are no great difficulties in the use of the hopper dozer. Careless driving may spill oil on some alfalfa and kill it. If these machines are to be really effective, they must be used before the grasshoppers get their wings. The first crop of alfalfa should be cut as early as possible, and the hopper dozers should follow the rakes as closely as may be. On the whole, they should be used only where plowing and harrowing have not been done or have failed to keep the grasshoppers in check.”

Of the use of this implement or machine Prof. S. J. Hunter has this to say:

“The height of the runners depends upon the height of crop to be protected. It is important that there be no timbers in front of the pan, so that its front line may come in contact with the grain passed over. The insects then fall directly into the fluid. When ready for use place two buckets of water and one-half gallon of coal-oil in a pan, and then drive back and forth across the end of the field where the grasshoppers are entering until you have filled the pans; remove the insects, replenish with oil and water, and continue until the field is rid of the pest.

“Many grasshoppers will be seen strike the sheet-iron back, drop into the pans and immediately jump out again. Those farmers who observed the experiments were at first of the opinion that the locusts that jumped out had jumped away ‘to live another day.’ The writer asked those interested to watch the insects and note the actions of grasshoppers that had jumped out. In every case the report was that the insects became sick and soon died. In fact, persons going over fields where a day or so before the hopper dozer had been at work, were impressed with the number of dead grasshoppers on the ground. An examination showed the presence of coal-oil upon the body. This kerosene and water is an external irritant, and my observations have been that the mixture is more effective than the oil alone.

“The use of the machine may be best shown by examples. In Ford county, Kansas, a large tract of alfalfa was cut, and the locusts at once began moving into a large field of Kafir corn which had been sown broadcast. The hopper dozer was drawn back and forth across the end of the corn field nearest the alfalfa land until a portion of the field about twenty rods deep had been gone over. Here it was apparent that there were very few grasshoppers; or, in other words, the advance line of the locusts’ march only extended twenty rods into the field. Two days later the same area of ground was covered, but not as many insects were taken. Grasshoppers no longer entered this corn and the hopper dozer was no longer used at this point.

“It has been my experience with this machine that after it has passed over vegetation it does not injure the plants, but in some way renders the vegetation distasteful to the grasshoppers, so that they turn their course and seek food elsewhere. I have observed that these native grasshoppers enter a field from one corner or side, and that they are not as a rule scattered over the whole field, but occur in great numbers in patches. This being the case, it is evident that with very little labor with this machine the products of a field can be given full opportunity to mature.”

ARMY WORMS

In Nebraska the fall army worm has caused considerable damage. It is distinct from the true army worm, having small hairs growing out from small black spots; it has a whitish “Y” shaped mark upon the head. The parent of the worms is a moth of a yellowish, ash-gray color. The female moth deposits her eggs in clusters upon the leaves and stems. With the approach of cold weather the worms pass into the ground and enter the chrysalis stage about one or two inches below the surface. When very numerous the only effective treatment is to disk thoroughly in the spring.

BIND WEED

Bindweed, belonging to the morning-glory family, is one of the meanest weeds that annoy alfalfa raisers. It spreads from the root, and is more than liable to smother out alfalfa or any other crop which tries to occupy its ground. If infested fields could be grazed closely with hogs or sheep, they might keep the bindweed down and finally eradicate it. If this cannot be done, the only remedy is to plow and use the land for some other crop.