Fuzzy (nondelinted) seed may be treated by dust applications of the appropriate fungicide, but slurry treatments are also used. Delinted seeds are treated easily by the slurry method.

In localities where the pink bollworm is a problem, quarantine regulations have been established to help prevent its spread. Seeds sent from an area of pink bollworm infestation to another area must receive appropriate treatment to assure bollworm-free seeds in the shipment. Steam sterilization treatment of all cotton seeds is practiced in Arizona. Extreme care is necessary to prevent damage by overexposure to heat and steam. Methyl bromide gas or other approved treatments may be used in other States.

Cotton seeds and the attached fiber (seed cotton) are harvested by hand or machine. About 5o percent of our cotton crop is harvested by hand. The worker grasps the seed cotton and picks it from the bur or snaps the bur containing the fiber and seed from the stem. The seed cotton is placed in a bag or basket and carried to a wagon or trailer. When the trailer is fully loaded, it is taken to a cotton gin, where the seeds are separated from the lint by ginning.

The procedure in machine harvesting is like hand harvesting, except that the machine replaces human hands in the removal of the seed cotton from the plant. The two machine-harvesting methods are picking and stripping. Mechanical picking by spindle machine removes only the lint and seed from the plant. The burs, unopened bolls, and plant are left intact. Mechanical stripping removes the burs, bolls, and some leaves and stems from the plant. Stripping is necessarily a once-over operation and must be conducted after frost or defoliation.

Mechanical picking by spindle machine can be done several times as the crop matures. It is often possible therefore to obtain more uniformly mature seed from mechanical picking than from once-over stripping. The Far Western States harvest up to 90 percent of the crop by this method.

Hand snapping and machine stripping are practiced chiefly in the western parts of Texas and Oklahoma, where about 30 percent of the United States crop is grown. Picking by hand or spindle machine is practiced in the rest of the Cotton Belt.

The precautions to be observed in harvesting to maintain high quality are generally like those needed to maintain the quality of the cotton fiber. Timing the harvest when the cotton is fully and uniformly mature is first. Clean harvesting with a minimum amount of such material as grass, leaves, and plant bark permits minimum handling and cleaning in the gin. It reduces the possibility of mechanical damage from excessive machining of the fiber.

To reduce leaf trash in the harvested cotton, the leaves often are removed from the plant or killed by the application of a chemical in spray or dust form. The chemicals that remove the leaves from the plant are called defoliants. Those that kill the leaves on the plant are called desiccants. Defoliation is practiced primarily to aid mechanical picking. Desiccation is used chiefly to facilitate stripping before frost.

Cotton should not be harvested while it is wet from dew or rain. If seed cotton is stored in the trailer or elsewhere at a moisture content of 12 percent or more, heating will occur and damage the seed and fiber. Damp cotton requires more processing in the gin and exposes the seeds to more mechanical damage.

The time of harvest of the cotton crop may affect the quality of seed. In parts of the irrigated West where it is more efficient to harvest only one time by mechanical harvester, it is necessary to defoliate before the first killing frost or to wait until after frost for the single harvest.

For the production of the best seed, it is necessary to harvest the first part of the crop before first frost to assure that all seed saved for planting will be fully matured. Therefore the practice of hand harvesting the early-season crop for planting seed is common in some places. The agencies handling cotton seed will not accept seed harvested after frost except in an emergency.

In the rain-grown areas of the Cotton Belt, adverse weather may lower the quality of the seed. Excess rain in the early or mid part of the harvest season may be harmful. In years of bad weather, such as 1957, substandard seed may be accepted from necessity. Most of the larger companies operate at enough different locations to counterbalance this problem in most years, unless unusual weather occurs generally over large areas.

If the seed is suspected of having poor quality following excessive rainfall, some checks are available to the seedsmen. A preliminary free-fatty acid test of the seed may be used to pinpoint germination potential. Excessive free-fatty acid is an indication of low quality, and this advance information can be of value to the seeds-man in saving his planting seeds.

The storage of seed with excess moisture because of rainfall just before harvest may result in the lowering of seed quality or the destruction of the seed. Most distributing organizations have proper storage bins, including facilities for drying moist seed with forced air.

All of the varietal maintenance and production programs we have discussed are efficient and successful. If the farmer plants genetically pure seed of the variety or varieties recommended for his soil and climatic conditions, he is sure he has the best possible seeds.

THE PRODUCTION of planting seed of leaf and stem fiber crops is on an experimental basis in the United States. There is no large commercial production of fiber crops other than cotton in the Nation. Flax and hemp are no longer produced for fiber in this country, but seed stocks of the best varieties that have been developed by research agencies are maintained.

Kenaf has shown some promise of being a good substitute for jute in the event of emergency needs. Considerable research on this crop has led to varieties that are high yielding and resistant to some of the major diseases that attack the crop. The seed can be harvested with machines, but the acreage is so small that only limited amounts of seed are maintained.

Other fiber crops sansevieria, ramie, phormium, and jute are propagated vegetatively. Research in mechanizing the propagation, growing, and harvesting of some of them is carried on by public agencies.

BILLY M. WADDLE became Assistant Branch Chief of the Cotton and Cordage Fibers Research Branch, Crops Research Division, Agricultural Research Service, at Beltsville, Md., in 1958.

REX F. COLWICK became Head of Cotton Harvesting Investigations of Harvesting and Farm Processing Branch, Agricultural Engineering Research Division, at State College, Miss., in 1959.