Effects of Method of Harvest on Flue‐cured Tobacco. I. Agronomic Factors1

The optimum in mechanized harvesting of flue‐cured tobacco (Nicotiana tabacum L.) may involve the removal of all leaves in one operation. Field experiments were conducted during the 1968 and 1969 growing seasons to evaluate 12, 16, and 20 leaf topping heights and normal and once‐over harvesting methods for yield, value, and price of flue‐cured tobacco. A separate analysis was utilized to determine stalk position effects within the three topping heights. A significant year effect and its interactions, probably resulting from excess water received in 1968, were noted. The tobacco from the normal harvest method had a greater yield, value, and price than that harvested by the once‐over method, resulting from overmature bottom and immature top leaves, both of which cause lower dry matter yields and a lower price/45.2 kg. The high‐topped plants produced the greatest yield but the lowest price, reflecting greater amounts of lowervalued tobacco from the bottom and top leaves. Yield was lowest at the lower stalk positions, increased to a maximum near the middle stalk positions, and then decreased at the upper stalk positions. Price was at a maximum at the lower‐middle stalk position and decreased in both directions. Leaves harvested by the once‐over method were lower in yield and price at the lower and upper stalk positions as compared to leaves harvested by the normal method. Disregarding the extreme lower and upper stalk positions, the once‐over harvest method resulted in leaves that were comparable to those harvested by the normal method.