Pitcher plant, Sarracenia, Close up showing open tubes.

Pitcher plant, Sarracenia, Close up showing open tubes.

Trailing ice plant, Delosperma cooperi, Side few of a few open vivid pink flowers with unusual central stamens.

Trailing ice plant, Delosperma cooperi, Several open vivid pink flowers with unusual central stamens.

Saguaro cactus, Carnegiea gigantea, Dramatic view from below of a single stem with arms branching upwards towards a blue sky with wispy clouds, its shadow on a white wall.

Witch hazel, Hamamelis mollis, Two leaves on two twigs crossing and backlit against a dappled background.

Madagascar ocotillo, Alluaudia procera, Close side view of small leaflets in patterns along a spiny woody stem, Backlit.

Madagascar ocotillo, Alluaudia procera, Close side view of small leaflets in patterns along a spiny woody stem.

Madagascar ocotillo, Alluaudia procera, Close side view of small leaflets in patterns along a spiny woody stem.

Canna indica, Close up of unusual purple seed pods in autumn.

Oak, Quercus robur, Acorns growing on the branches of tree in late summer.

Oak, Common oak, Quercus robur, Side view of fairly mature tree with no leaves, silhouetted against the misty dawn sky in an English field.