Brittain B. Robinson

“ By harvesting before the male plants die, the retting of both male and female plants is more uniform, as both types of plants are still green and growing. The harvesting period may extend for 2 weeks or longer. Very early harvested hemp may produce a finer and softer fiber than that harvested later, but it is usually weaker. The fiber from hemp that has been harvested so late that many seeds have matured does not possess so good cordage and textile characteristics as fiber from hemp harvested earlier. ”

“ Hemp grown for fiber should be sown with a broadcast seeder or with a grain drill. A drill with 4 inches between drill tubes is preferred to one with 6 inches or more. The seed should not be planted deeper than 1 inch, and a depth of 1/2 inch is preferred. If the seed is planted deep, the hemp seedling is not capable of pushing its way to the surface of the ground. A slight crust on the ground frequently results in a poor stand. If the seedbed is loose, disks on a seed drill may cut too deep into the soil and the seed will be sown more than 1 inch deep. ”

“ A good practice in planting hemp for fiber production is to sow around the edge of the field next to the fence a 16- to 18-foot width of small grains, which may be harvested before the hemp. Space is thus provided for the harvester to enter the field and begin cutting without injuring the hemp. It also prevents hemp plants at the edge from growing too rank. Uniform plants are necessary for uniform fiber quality. ”

“ Dry hemp stalks should be tested when possible to determine the degree of retting. Three to six stalks are taken in both hands and bent back and forth to perform the break test. If properly retted, the fiber should not break when the woody core breaks. The hurds should fall free of the fiber in the breaking and shaking between one's hands. If the hemp is only partly retted, some hurds will adhere to the loosened fiber. Unretted hemp fiber is usually green or light yellow. Dew-retted hemp is usually slate gray or black. ”

“ In a program calling for small spring grains and corn, the farmer should plan to plant his hemp between the time he plants his small grains and the corn.
Seeding
Hemp grown for seed production should be sown in rows or hills. The hills are commonly spaced 5 by 5 feet, with 6 to 10 seeds to the hill, planted not more than 1/2 inch deep. The plants are thinned to 3 to 5 to a hill. If care is taken to save seed, about 11/2 pounds wall sow an acre. Most farmers use more seed, and frequently the crop is replanted because of late floods or failure to obtain good stands. ”

“ If the hemp stalks are well butted in the bundle when processed, the milling operations can be carried out more economically. Tangled, uneven bundles are more difficult and require more time to handle. The yield of high-value long-life fiber is much greater if the stalks are well butted.
Hemp stalks are considered most desirable if they are less than half an inch in diameter. The thickness of a pencil is frequently used to illustrate the size of desirable stalks. The larger diameter stalks have a lower percentage of fiber than finer stems, are harder to break, and produce more tow fiber. ”

“ Hemp yields have been extremely variable when this crop has been planted in new areas by inexperienced farmers. In Wisconsin and Kentucky, where only experienced farmers have grown the crop in recent years, the yields have not varied a great deal. The crop has been reasonably dependable and has not often been injured by storms or droughts.
The average yields per acre for experienced farmers are approximately 21/4 to 21/2 tons of air-dry retted hemp stalks; 850 pounds total fiber. Under the Wisconsin machine-milling system the yields may average 450 pounds line fiber and 400 pounds tow fiber ”

“ Fiber hemp grows successfully on soils of the Clarion, Tama, Carrington, Maury, Hagerstown, and Miami series, which, in general, are deep, medium-heavy loams, well-drained, and high in organic matter. Artificially drained areas of the Webster, Brookston, and Maumee series also give satisfactory yields. These soils are among the most productive soils of the Corn Belt. They produce average yields of 50 to 70 bushels or more of corn per acre. If land will not produce from 50 to 70 bushels of corn per acre, it should not be planted to hemp for fiber production. ”

“ In the United States the common« 5 » practice (known as dew retting) is to cut the crop and let it lie on the ground. Exposure to the weather causes the fiber in the outer part of the stem to separate. Light snows and alternate freezing and thawing seem to improve or make the retting more uniform.
How to grow it Soils and Fertilizers
Hemp should not be grown on poor soils. To obtain good yields and fiber of high-quality, it is necessary to have a growth of uniform stalks 6 to 8 feet long. Short stalks, from poor nonfertile soils, seldom produce a high-quality fiber. ”

“ In the northern part of the Corn Belt the hemp usually does not grow so tall and therefore can be handled more easily with machines. During the first World War hemp-harvesting machinery was developed. These harvesters (see above) in one operation cut an 8- or 9-foot swath and elevate the stalks to a quarter-circle platform where they are turned automatically and dropped or spread on the ground for retting. The butts of the stems all lie in the same direction and are relatively even. The thickness of the layer of stalks in the swath influences the speed and uniformity of the dew retting. ”

“ A few days too long in the field may make the difference between retting and rotting. Therefore, it is most important that inexperienced farmers obtain the assistance of the hemp-mill superintendent or an experienced grower in determining when to stop the retting. ”