A Botanical Holmes

Our botanist, an ageing Holmes,
In deerstalker and knickerbockers,
Had eyes like Sherlock's, spying without a glass
Along a mile of country pathway, more than fifty flowers

He fathomed history too. In woods
Whose floor was dark with foliage
Of Dog's Mercury, deducted that it signified
A woodland planted centuries ago.

Along the rim of Hole of Horcum,
Gouged by glacial waters under glacial ice
He found Dwarf Cornell, here and nowhere else
In England, since the melting of the ice.