GENERAL INFORMATION. 261 



Comparative immunity for one season too often causes the farmer to neglect the destruction of the late brood of 

 worms left upon the suckers which spring up after the crop is harvested, large numbers pupating and hibernating, 

 protected by the forgotten and neglected trash of the tobacco-field. Catching the moths with ingeniously-contrived 

 traps, poisoning them with sweetened cobalt dropped into the bloom of the Jamestown weed, or killing them with 

 paddles as they hover about the tobacco plants after sunset, are all practiced. Recently, as in Teuuessee, porcelain 

 imitations of the blossom of the Jamestown weed have been introduced. These are fastened upon sticks, set up at 

 short distances apart throughout the tobacco-field, and are supplied with a few drops of poisoned sirup. They are 

 cheap, will last with ordinary care a lifetime, and are highly recommended by planters who have used them. A 

 knowledge of the transformations of these insects will enable the observant farmer to do much to reduce their 

 numbers, and if it were possible to secure prompt measures throughout a considerable section of country, or even 

 by the growers of a large neighborhood, much disagreeable labor might be saved. 



The moth deposits an egg of a sea-green color, not larger than a mustard-seed, upon the surface of the leaf. This 

 egg gradually assumes a cream color, and from it, in due time, a tiny worm issues, not larger than a horse-hair, 

 and about one-eighth of an inch in length. The process of hatching embraces from twenty-four to thirty-six hours, 

 depending upon the condition of the weather. The worm begins to eat immediately, making first a small hole in 

 the leaf, through which it passes in hot weather to the under side, and occasionally the eggs are there deposited 

 by the moth. This worm, though voracious, does little damage for four or five days. Its power of destruction 

 increases exceedingly with each day, and this makes it highly important to go over the field often in search of 

 them. 



When the horn-worm has attained full size it stops eating, comes down from the plant, and usually burrows 

 into the ground close to its last feeding-place, but not unfrequently crawls away some distance to find soil sufficiently 

 soft to enable it to get some inches below the surface. Here it becomes quiescent, casts off its larva skin, and 

 assumes its pupal form. It is now oval in shape, four times as long as it is thick, about 1J inches in length, and 

 the hard, glossy envelope is of a bright chestnut color. The forward end is prolonged into a long, tube-like 

 appendage, bent backward and firmly attached to the chest, forming a loop like a pitcher-handle, this tube 

 eusheathing the tongue, which is so remarkably developed in the perfect moth. Only under peculiar circumstances 

 are these pupae found at a greater depth than may be reached by deep plowing. A further means of reducing the 

 number of these insects is therefore by fall or winter plowing the tobacco-fields. It must be said, however, that 

 even if every egg, worm, moth, and chrysalid in a given neighborhood were destroyed, high winds, or even the 

 lighter breezes of the summer evenings, bring other moths many miles. The tobacco-grower should instruct those 

 in his employ not to destroy any horn-worm found with the cocoons of the parasite Microgaster congregata attached 

 to its body. These cocoons are white, of a regular oval form, a little more than an eighth of an inch long and about 

 one-sixteenth of an inch broad, and resemble small grains of rice. From ten to a hundred of these cocoons are 

 found upon a single horn-worm. The worm so infested may be removed from the tobacco plant, but should be 

 handled carefully and placed where the cocoons may not be injured, so that the parasites may hatch undisturbed. 

 The flies which issue from the cocoons are black, with clear, transparent wings and legs of a bright tawny color, 

 the hue of beeswax, with the hind feet and the tips of the hind shanks dusky. 



The testimony of all tobacco-growers points to the one conclusion about insect enemies. No methods of 

 prevention or destruction can justify a single day's neglect to search for and destroy cut-worms about newly-set 

 plants and the eggs and larva} of the sphinx moth upon the expanded leaves throughout the season. 



DISEASES OF THE TOBACCO PLANT. 



The tobacco plant is subject to certain diseases, few in number, however, and rarely resulting in very serious 

 damage. Unfavorable seasons, too wet or too dry, often reduce the yield and impair the value of the product ; but 

 diseases, properly so called, seldom affect more than a few plants, or perhaps a small portion of a field. Schedules 

 returned from widely-separated districts mention the same diseases, all of which result from deficiencies in the 

 soil or its preparation, or from peculiarities of the seasons during growth. 



A disease known in New England as "brown rust", and in the South as "firing" and "field-fire", prevails to 

 some extent every year. It appears in very svet or very dry weather, and reports concur in the opinion that it is caused 

 by violent changes from one extreme to the other. A plethoric, plant with the supply of moisture suddenly cut off, and 

 a lean plant forced by excessive moisture to rank growth a leaf perishing in spots for lack of sustenance, and 

 another from the opposite cause present variable conditions, developing "rust" or "fire". This disease is not so 

 prevalent in some districts as formerly, which is attributed by some planters to the substitution of new for old 

 varieties ; but it is more probably due to planting upon a different character of soil, or to more thorough drainage 

 and improved culture. Sometimes, though rarely, the entire plant is involved, drooping and withering through 

 excessive humidity. This is the " black fire ", a strictly wet-weather disease. In dry weather the plant sometimes 

 parches up, as if scorched. In uniform, ordinary seasons it does not appear. Injudicious use of heating manures is 

 assigned as sometimes the cause of firing, and undoubtedly does occasionally produce " red " or dry- weather firing. 

 Thorough drainage is regarded as the best preventive of this and its kindred diseases. i 



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