The study included K 326, NC 71, and Speight 168 varieties and compared recommended nitrogen rates to the recommended rate plus 20 pounds of N and high-topping to normal-topping heights.

• 研究包括K326、NC71和speight168品种，对推荐氮用量和在推荐氮用量基础上加20磅N以及高打顶和正常高度打顶进行了比较。