Duane Schott, age 11, of Wichita, Kansas, for his question:
Do ferns have flowers?
Most flowers produce seeds for the next generation of plants. The ferns have a very different system for handing on life to the next generation. They have no flowers because they do not need them. Besides, they arrived on earth long ages before the plant world invented flowers. The flowers grew more and more lovely, but the ferns never followed the fashion. After all, their feathery fronds also were lovely and their old method of multiplying already had proved successful through millions of years.
Our beauteous earth has more than 350,000 different plants to clothe itself in fresh, green mantles. More than half of them bear flowers to add colored embroideries to the greenery. The ferns add no flowers, but their feathery green fronds add some of the prettiest frills and fringes, tassels and laces. There are about 10,000 different fern species and if they were tinted with rainbow colors we might forget to notice the glamorous flowers.
Some ferns grow on mountainous slopes that are as high as two or three miles and a few brave ones grow within the Arctic Circle. Some are small enough to hide themselves in carpets of moss. Others are 40 foot tree ferns with woody trunks. They grow on warm Pacific islands and look like stately palms topped with dainty parasols of green plumes. Others are air ferns, growing high on jungle boughs. They absorb their moisture from the air and take their food from dusty debris in the rough bark.
But most ferns live quietly in moist, shady woods. Their leafy fronds grow about one or two feet high. The young leaves start as thick stems with gracefully coiled tops. As they grow, they uncoil and spread open their lacy green designs. Some ferns sprout their fronds in leafy rosettes, others sprout new leaves from horizontal stems lying on or just under the ground. All of their leafy fronds can start the complicated process of fern reproduction.
This happens when spore cases form on the underside of the leaves, like rows of brownish pimples. The ripe cases burst, scattering the tiny spores. When a lucky spore falls on a suitable moist spot, it develops into a plant shaped like a minature green heart. It looks nothing like its ferny parent and never will. So we call it a first generation fern. Its job is to develop male and female cells. When these eggs are fertilized, they produce second generation plants that become what we know as ferns.
This method of reproduction is called "alternating generations" because it develops through two very different plant types. It seems much more complicated than the seed method used by flowering plants. Nevertheless, it has a much longer record of success. More than 200 million years ago, when ferns crowded the carboniferous coal forests, it was the most advanced form of plant reproduction in the world.