DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY
A seed of mistletoe (Viscum album) on a cherry tree (Prunus incisa). The seed, (green, 3mm across) is encased in a thin coat (white). It is fixed to the tree by a viscous sticky fluid that surrounded it in the berry. This has dried to produce a firm bond between the seed and the tree. Two short green outgrowths with bulbous tips (green) are visible. These are hypocotyls at an early stage of growth. The tip of each will eventually attach itself to the bark and produce a root (a "sinker") that will grow through the bark of the tree. Root development is slow and may take several months. V. album is parasitic on a variety of trees. Its seeds are dispersed by birds. Some species eat the berries and spread the seeds in their droppings; others wipe the sticky seed from their beak without ingesting it. The seed here was placed on the branch by hand six weeks before the picture was taken.
Model release not required. Property release not required.