Colour-enhanced Scanning Electron Micrograph (SEM) showing a grain of clover (Trifolium campestre) pollen. Known variously as Low Hop Clover, Field Clover, and Plains Clover, the heads of this species are densely packed with tiny yellow pea-shaped flowers that turn from a creamy colour to rusty brown before going to seed. One plant typically has 20 to 40 flowers per head, and numerous flower heads on branching stems. Image width: 25.6 micrometers. Magnification: 3906x if the image is printed 10 cm wide.