Seed production and marketing; Improving varieties by modern methods of breeding; The work of crop-improvement associations and cooperative seed distributing agencies; Special cultural preactices and equipment necessary in growing good seed; Growing and marketing seed corn; Producing small grains for seed; Producing seed of the clovers; Producing alfalfa seed; Kentucky bluegrass-seed production and marketing; The production of seed of timothy, redtop and other grasses; Cotton seed production; Growing and marketing seed potatoes; Producing seed of field beans, soybeans, cowpeas and vetch; Growing seed of cucumbers, melons, pumpkins and squashes; Growing seed of the crucifers (Cabbage, Cauliflower, Kohlrabi, Brussels sprouts, kale, Collards, Turnip, Rutabaga, Radish, chinese cabbage, cress, horse radish and sea kale; Growing seed of solanaceous vegetables tomato, pepper, egg pant, husk tomato or ground cherry, wonderberry, tobacco; Growing seed of garden and canning beans and peas; Producing seeds of garden beet and sugar beets, swiss chard and spinach; Growing seed of carrots, parsnip, celery; parsley and other umbelliferous plants; Growing seed and sets of onion, leek, garlic, shallot, ciboul or welch onion, chives; Growing seed of lettuce, endive, chicory, salsify, artichoke; Growing seed of asparagus, okra, rhubarb; Where the nation's seed is produced.