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There are many different seeding conditions in North America, so a wide variety of row spacings, seeding widths and attachments must be provided. Grain Drills with row spacings of 6, 7, 8, 10, 12, 14 and 18 inches (15.2, 17.8, 20.3, 25.4, 30.5, 35.6 and 45.7 cm) are available on standard machines and for row crop work. Furrow openers can be arranged for most of the desired spacings. Press Drills are specially designed for hooking up, side by side, so almost any desired seeding width can be obtained between 7 and 70 feet (2.1 m and 21.3 m).
development of a new model grain drill
Olsson, N.O. 1971. DEVELOPMENT OF A NEW MODEL GRAIN DRILL. Canadian Agricultural Engineering 13(1):2-3.
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