Fig. 1

Manually measured traits. An example of manually measured tassel traits. Tassel length is the distance from the lowermost branch to the spike tip. Spike length is the distance from the uppermost branch to the spike tip. Branch number is a count of primary branches, i.e., those that intersect the central axis of the tassel, and not those that originate on another branch. Not pictured is tassel weight, which was measured as the average weight of three dried tassels per plot