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.
Ferns grow best in moist, humid habitats with low light. They are very common in rainforests. Ferns have delicate leaves called fronds. They start out curled in a tight ball that opens as the frond grows. Ferns have horizontal stems called rhizomes.