There is an almost universal agreement among practical growers and plant pathologists that this crop should never be cultivated when the plants are wet from dew or rain. The Cornell Station (Cornell Station Bulletin 255) comments as follows in regard to this matter: "Cultivating or working beans when wet should be avoided as much as possible. On this point there can be no dispute. The character of the parasite causing the disease and the practical experience of the growers everywhere show that this recommendation is correct."
Garden beans must be picked by hand. When grown on a large scale a great many pickers are required. Colored labor is used almost entirely for this work in the South. Figure 61 shows a large force harvesting a crop of wax beans at Norfolk, Virginia. The pickers of snap or string beans are generally paid a definite amount a basket.
Field beans were formerly harvested by pulling, but the special harvesters now employed materially reduce the cost of this operation. L. C. Corbett (United States Department of Agriculture, Farmers' Bulletin 289, p. 14) describes it as follows: "This implement is built on the principle of a pair of shears, and consists of two long steel blades mounted upon a strong framework carried upon wheels. The long shearlike blades are set to cut the roots of the plants just beneath the surface of the ground. Above these blades guard rods or guide rods are so arranged as to move from their original positions the plants whose roots have been severed and, since the implement is designed to cut two rows of beans across the field, the plants of two rows are thrown together in a single windrow. This clears space for the passage of one of the animals in the team, so that it is necessary for only one to pass through the standing crop, thus decreasing the amount of loss by shelling which would result from both animals being driven through the standing crop."
Fig. 6l. Picking String Beans At Norfolk, Virginia.
After cutting, the rows may be thrown together into small piles for curing, or they may be moved into windrows by side-delivery rakes. The crop is allowed to ripen fully in the field, so that only a few days after cutting are required for curing. If the weather is wet, the piles must be turned frequently to prevent damage to the beans. After thorough curing the crop is stored in barns after the manner in which hay is handled, and threshed whenever it is convenient, but not until cool weather. The old method was to flail, while now bean threshers are generally employed. These machines are moved from farm to farm, just as grain threshers or separators are used.
In the districts producing large amounts of field beans the threshed product is delivered by the farmers at elevators or special bean houses managed by dealers who attend to the work of cleaning, grading and picking. In Michigan there are over 200 bean elevators provided with the best machinery for preparing the crop for market. While the machines remove most of the dirt and broken beans, some hand picking is necessary to get the crop thoroughly cleaned. To facilitate this tedious work a machine spreads the beans thinly on a revolving broad belt, which passes slowly before the picker. The speed of the belt is controlled by the person removing the defective beans. Girls and women are employed extensively to do this work, some houses maintaining a force throughout the year. Dealers who contract for the crop, generally furnish bags to the farmers free of charge.
String or snap beans are often sorted before marketing to remove broken or damaged pods. They are generally carried in bushel hampers and shipped by express and refrigerated freight, a car holding about 600 hampers. The hampers should be well filled and the pods as fresh and plump as possible. Half-bushel baskets are often used for local markets.
Green shell beans are usually marketed in berry baskets in both pint and quart sizes. Green shell limas are regarded as quite a luxury and usually command good prices.
In 1900 the average yield of field beans in the United States was 11 1-5 bushels an acre. The most successful growers often obtain double this yield. The price varies considerably, but ranges from $1.50 to $2 a bushel. Snap beans should produce 200 bushels an acre, although the yield is often less. A net return of $100 an acre, after deducting freight and commission charges, is regarded as satisfactory. Prices vary greatly from year to year, and the net profits some seasons are not encouraging.
While the bean has a number of insect enemies, the weevil is the most destructive. This insect is about ⅛ inch long and covered with fine brown, gray and olive pubescence. Ovi-position begins in the field, where the female deposits eggs in holes in the pods made by the jaws or by the drying and splitting of the pods. Breeding continues after storage, a large number of individuals frequently developing in a single bean. The beetles emerge the following spring to repeat their work of destruction.
Field treatment of any kind has not been satisfactory, so that preventive measures before planting must be employed. Fumigation with bisulphide of carbon is the most effective treatment. The New Hampshire Station (N. H. Bul. 59) recommends the following plan: "Use an ordinary coal oil barrel, which will hold close to five bushels of beans. This can be treated with 3 ounces of bisulphide of carbon, which may be poured on the beans. Care must be taken to close the top tightly; the exposure should be for 48 hours. The bisulphide should be of the best quality because this will vaporize without any residue. The vapor of this substance is very inflammable and the work should, therefore, be done at a distance from other buildings and no light of any kind be brought near."
Anthracnose (Colletotrichum Lagenarium) is the most common and the most destructive of the bean diseases. It is a fungous disease, which attacks all parts of the plant except the roots. Diseased seed is often the source of the malady. The young tender stems may become affected and the plants killed when conditions are favorable for the parasite; or it sometimes appears later on the pods, as well as on other parts of the plant. The disease is very noticeable on the yellow pods of wax varieties, which they reduce in value or render unfit for market purposes. Figure 62 illustrates the diseased pods. The Cornell Station (Cornell Station Bulletin 255, p. 436) makes the following statement in regard to this disease: "The spots or cankers are black with reddish or yellowish margins. Most growers are also familiar with the disease on the seed itself, especially on the white beans, where it makes rusty, red spots of various sizes, sometimes involving nearly the entire seed, though ordinarily only producing a slight discoloration on one side. The disease enters the seed by way of the pod, the fungus penetrating from the outside into the young and tender seed. . . . When the diseased seeds are planted in the soil, and first come through the ground, they are sure to show the small black cankers on the cotyledons or seed leaves and a little later on the stems."
Fig. 62. Bean Anthracnose.
Numerous investigations have been made pertaining to the control of bean anthracnose. Seed treatments of various kinds and spraying have been tried, but with unsatisfactory results. The planting of healthy seed is unquestionably the best preventive measure. If seed and soil are free from the disease, there can be no anthracnose. Seed selection, then, is of prime importance, and the matter should have closer attention among both home and commercial growers.
Fig. 63. Field Of Garden Beets.