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Once the flag leaf has emerged, the swelling of the developing ears within the flag leaf sheath becomes visible as a boot (DGS 40–49; Figure 1.11). It is approximately during this booting phase that cell division by meiosis occurs to produce the male (pollen) and female (ovule) gametes of the flowers. Booting is soon followed by the emergence of the ear above the flag leaf (DGS 50–59; Figure 1.11). At ear emergence, the structure and colour of the ears can be used to distinguish wheat cultivars. For example, the length of the awns extending from the lemmas (Figure 1.12) can either be short (awnless cultivars) or long (awned cultivars), as compared in Figure 1.13. Awns are a wild‐type adaptation that would have aided seed dispersal. However, there appears to be a small yield advantage for awned cultivars in warmer areas, and particularly for preventing excessive grain shrivelling in dry conditions (Rebetzke et al. 2016).