Once the crop reached boot stage (head enclosed in swollen flag leaf sheath), the top of the plant was cut with garden shears just above the leaf below the flag leaf for the subplots randomly designated for top removal at
boot stage. At anthesis, approximately 10 days after boot stage, the top of the plant was cut with garden shears just above the leaf below the flag leaf for the subplots randomly designated for top removal at anthesis stage.
After top removal, the heads were discarded and were not included in further analyses. No top removal
occurred until harvest (see below) for the subplots designated for no removal.