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.
Fern Structures and Reproduction. Ferns are seedless, vascular plants. They contain two types of vascular tissue that are needed to move substances throughout the plant. Evolutionarily, this addition of vascular tissue to plants is what allowed ferns to grow up and out rather than just spreading along the ground.