Fig. 3

Capitate trichome development on cannabis strain MD, lower bract surface, at 3 and 6 weeks of inflorescence development. a At 3 weeks, most capitate trichomes at the tip of the bract are sessile but a few (arrows) have started to develop stalks. Nonglandular hairs can be seen. b Stalked-capitate trichomes forming first along the midvein of a bract; abundant sessile-capitate trichomes can be seen in the background together with nonglandular hairs. c At 6 weeks, stalked-capitate trichomes can be seen densely packed together. d A range of stalk lengths can be seen, with one trichome stalk on which the head has been detached (arrow). e A view of the edge of a bract at 6 weeks of inflorescence development, showing greater abundance of stalked-capitate trichomes on the lower compared to upper bract surface. Trichome stalk lengths are variable