On the Cover: Cell wall expansion in growing Medicago truncatula root hair cells occurs almost exclusively in the apical tip. A time-lapsed image series at 2-min intervals shows the growing hair on the left. Images on the right are time composites of fluorescent beads decorating the expanding tip. Beads moving apart, due to the underlying cell wall expansion, provide a means to measure the local strain rates and anisotropy of expansion. Readers are referred to Shaw et al. (pp. 959–970) for more details.