![]() The young fronds sprout directly from the rhizomes. At some points, the rhizomes can grow vertically into a short trunk. Sometimes, rhizomes may even climb up a tree. Laterally growing rhizomes can creep along or under the ground to expand their territory. The rhizome is the stem and root in combination and looks like a branching vein system. Pinnate – The fronds are divided into segments completely separated from each other maidenhair spleenwort).Pinnatifid – The fronds are divided into segments (sensitive fern).Simple – The fronds are undivided (bird’s nest fern).Various degrees of leaf divisions are shown in the series of frond silhouettes. Pinnules can even be split into lobes and generate more complicated frond shapes such as beech fern, northern wood fern, and Maidenhair fern (my favorite fern).įern leaves display a variety of divisions depending on the species. Pinnae of some species can further divide into sub-leaflets, called pinnules. The frond may be simple and undivided, or it may be divided into many divisions (called pinnae). Fronds have a dual function – photosynthesis and reproduction.įerns’ blades grow in a massive variety of forms. As they grow and mature, these fiddleheads slowly unroll. New fronds are produced from the rhizome, and they are tightly coiled into a spiral (called a fiddlehead or crozier). The flat blade is the expanded, leafy part of the frond and the stalk connects the frond to the rhizome. The fronds are the leaves of the fern and consist of a blade and a stalk. The sporangia are reproductive structures and are found in clusters (called sori singular sorus) underneath the fronds. The rhizome is the stem of the fern plant. The fronds, the rhizome, and the sporangia are 3 major parts of the fern. The structure of fernįerns come in various shapes and sizes, but they all have 3 major parts – the fronds, the rhizome, and the reproductive structures called sporangia. They cannot grow in hot, dry areas like a cactus or cold frozen places like conifers. As we know them now, most ferns grow in wet areas under a forest canopy, along creeks, streams, and other sources of permanent moisture. Ferns are restricted and can only propagate in a suitably moist condition. The life cycle of ferns requires an intermediate plant stage called a gametophyte (the sexual phase in plants) between fern spores and maturity. Unlike the other vascular plants such as the flowering plants and conifers where the adult plant grows immediately from the seed, ferns reproduce via spores, and ferns do not have seeds and flowers. This is why some giant ferns can grow up to 20 feet tall compared to tiny nonvascular plants, such as mosses and liverworts.įerns are classified as the lower vascular plant division – Pteridophyta. Thus, we classify ferns as vascular plants. Ferns also have vascular systems that can efficiently transport water and nutrients. Even though they are so ancient, ferns already have true roots, stems, and complex leaves similar to current plants. They were thriving on Earth for two hundred million years before the flowering plants evolved. ![]() Their origins can be traced to the late Devonian period, approximately 360 million years ago – far older than dinosaurs! They pre-date the evolution of humans, mammals, reptiles, and birds based on the fossil record. ![]()
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