The sections of the light spectrum which the âredâ and âgreenâ cones perceive overlap and this is why red and green colour vision deficiencies are often known as red/green colour blindness and why people with red and green deficiencies see the world in a similar way.
Wood fern (Dryopteris) Plant these delicate, medium-sized ferns in mixed borders to show off their feathery fronds. Autumn ferns (D. erythrosora) are one of the few ferns with seasonal color variation and their fronds change from pale gold and pink in spring to green in summer and rusty copper in fall. The ferns spread by underground stems to form swaths in garden beds.
Tree ferns are true ferns. Like other ferns, they never flower or produce seeds. They reproduce from spores that grow on the undersides of the fronds or from offsets. A tree fernâs unusual trunk consists of a thin stem surrounded by thick, fibrous roots.The fronds on many tree ferns remain green throughout the year.In a few species, they turn brown and hang around the top of the trunk, much like palm tree leaves.ike other ferns, they never flower or produce seeds. They reproduce from spores that grow on the undersides of the fronds or from offsets. A tree fernâs unusual trunk consists of a thin stem surrounded by thick, fibrous roots. The fronds on many tree ferns remain green throughout the year.