Silphium

Herbaceous perennials, from the eastern half of North America, often tall, with typically yellow daisy-like flowerheads, through summer and autumn. These have opposite leaves, unlike the similar Helianthus, Helenium and Rudbeckia.

As with all 'daisy-like' flowers, the disc-flowers in the centre of the flowerhead produce nectar and pollen that are highly attractive to insects, such as bees, hoverflies and butterflies, while the leaves are palatable to the caterpillars of a range of garden moths.