Timing for wheat harvesting is unique throughout the world and depends on the climatic and grain moisture contents. Market values fluctuate in the supply season based on the harvesting output and growing conditions. In United States harvesting of the crop takes place in two seasons. Once from mid May to July, which is the winter crop and next in mid august to September which is the spring crop. Wheat is generally harvested when the moisture content of the grains drops down to 20%. During a low humid day the content generally reaches this level. The market discounts and the additional care in adjusting the combine from damaging the kernels due to higher moisture may sometimes lead to its harvesting at even lower rates.
Harvesting Technique
Combines are the equipments which are specifically designed for wheat harvesting. They work well on standing wheat and come with a rotary thresher or rasp-bar cylinder; these are adjusted in accordance with the moisture content, grain weight and amount of weed in the field. Combines have to be checked for cutting, feeding, threshing, sorting and cleaning of the grains. This makes sure that the refining of the grains for storage starts from this stage. Thresher speed, concave spacing and the sieve openings are set according to the moisture and species of the wheat.
Storage
Wheat is stored by techniques which manage protection against physical, biological and chemical damage. Controlled climate, airtight storage spaces, heat treatment for prevention of further moisture absorption, fumigation with gases, controlling rodents with insecticides and pesticides are all post harvesting procedures. Before the crop is marketed small scale storage is done in sealed bags, gourds, conventional bags, wrapped pits or bunkers. The bulk crop is stored in small scale and large scale basis. For the former cribs and underground fumigated pits are coveted, and when the storage is bulk then bunkers and bins are used.
