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4, Moth of dingy cutworm (Feltia jaculifera); B, another species of dingy cutworm (Feltia tubgotlcica), both one and one-half times natural size; C, moth of traveling cutworm (Feltia gladiaria), two and one-fourth times natural size. Other varieties and species of these moths differ but slightly from these In t he eyes of all except the scientist.
showers, the tobacco will cure a beautiful bright, goldenred color. Much the same methods are to be followed in curing Bur ley as is the case with cigar leaf or seedleaf.
CURING SEEDLEAF TOBACCO.
The method of curing practiced in the cigar tobacco sections of the United States, also Cuba and Sumatra, is entirely air curing,—it is accomplished by regulating the air and moisture, by opening or closing doors or shutters in the barn. Fire curing, that is, by the aid of artificial heat, or sun curing, by exposure to the direct rays of the sun, is seldom practiced. The modified Snow process has been tried with doubtful results, although at the Pennsylvania experiment station "the general character of the rapidly cured leaf was not inferior to that more slowly cured, and the dangers of disease were removed." The Wisconsin experiment station favors artificial control of temperature and humidity, after two years' experience with it, but does not state how leaf so cured came out of the sweat, or fermentation process, necessary after curing to fit the leaf for cigar making. In the Miami valley, a few planters put small, coal stoves into their barns, with pipe running up through the roof, and keep up a gentle heat during very rainy weather or a long-continued damp spell, admitting cold air at bottom and opening ventilators at top to carry off the hot, moist air. Undoubtedly this same method of artificial control will be perfected fo reduce pole sweat, pole burn or white veins.
But the system now in vogue is that which has prevailed for years. It has been improved by greater care in the construction of barns, but it is at best a crude and imperfect method, and one requiring vigilant attention to details, and a nice perception of alterations of temperature and moisture, to properly carry out. Yet Bo skillfal have the growers become, even with this crude process, that a good cure can be expected in the vast majority of cases, unless the crop has been damaged, or improperly grown in the field, and unless excessive top and dampness prevail at curing time. It is a phase in the existence of the crop that is looked forward to with great anxiety, and the grower breathes a sigh of relief when the curing is safely over and the crop is stripped and cased without injury.
The first point to avoid is the too rapid drying of the leaf. Drying is not curing, and the terms are in no way synonymous. The change of color and condition in the leaf is largely due to a process of fermentation, which takes place in the hanging tobacco, and for which a certain amount of moisture in the leaf is necessary. If the leaf is dried too rapidly, this fermentation is either prevented altogether, or checked to some extent, thereby affecting the result disastrously. As far as possible, the air in the shed, during the whole curing process, should be kept in such a condition that the tobacco will never become quite dry and brittle; it should never crumble when handled. To this end, after the first two weeks following the hanging, the sheds should be kept tightly closed during dry weather, and if opened it should be at night, or for a while upon damp and misty days. If the buildings are kept closed, the great amount of moisture evaporated from the tobacco will keep the air sufficiently damp, even in dry weather.
The second principle is to keep the air in the shed from excessive dampness, which, with heat, causes a destructive fermentation or rotting, which is entirely different from the fermentation of the curing process. For this reason, the buildings should be kept well opened and ventilated the first week or two after hanging, that the fresh currents of air may carry off the large amount of moisture evaporating from the tobacco, and also check any tendency to excessive heating. During the whole time of curing, after any protracted time of damp or warm, muggy weather, the sheds should be opened, until the tobacco is partially dried off. To carry out both these principles, the shed should be so constructed as to permit of its being tightly closed and also of its being opened and thoroughly 'ventilated. Light should be carefully excluded during the curing process, especially in its later stages, as it is found that
FlG. 61. TRAVELING ctrnroRM. One and one-half times natural size.
strong light has an injurious effect upon the color of the leaf.
Even under the most favorable conditions, a successful cure will depend largely upon good management. Tobacco is very rapidly dried out by means of a constant current of air, especially if this air is heated, undergoes very little if any chemical change, and retains to a greater or less degree its green color. Moreover, since the process of fermentation in bulk, accompanied by heat, depends upon and must be preceded by the changes in the leaf produced by gradual curing, it follows that tobacco that has been too rapidly dried loses, to a large extent, its ability to pass through the subsequent sweating process, and the tobacco remains permanently of a greenish color. If the tobacco is cured in a current of air, care being taken not to drive the moisture out too rapidly, a change takes place in the interior of the leaf that changes the color from green to brown. Finally, if tobacco is hung too closely, so as to prevent the free access of air, the color still changes from green to brown, but by a different process of fermentation, the leaf loses its tenacity and elasticity, becomes subject to pole burn and is more or less spoiled by rot.
The time required for "curing down" tobacco varies very greatly from year to year. Some seasons it progresses very rapidly,—so much so that a cure is completed in from six to eight weeks; again, it is slower, and three or four months are required. As a rule, quick curing is the best. It can only be accomplished when all the conditions are favorable. The seasons of 1891 and 1892 were remarkable for the rapid cures, and the result of the cures in these years was unusually satisfactory. Some years, however, the conditions are abnormally bad, such as was the case in 1872, when dense, heavy fogs settled over the Connecticut valley during the curing season, and the crop rotted on the poles, in spite of all that could be done to save it. This has gone down in the legends of the tobacco growers as the "bad year of '72." It is thus seen that very much depends upon the temperature and moisture of the outside atmosphere, although these conditions can be controlled to some extent, and often to a sufficient extent to effect a cure. But even with the best of care and the most favorable management, atmospheric conditions may prevail that render any curing abortive.
Goff has shown that in Wisconsin green seedleaf tobacco loses about 71 per cent of its weight during the