Quillworts produce two different types of spores

Published 8:18 pm Friday, August 18, 2023

By John Bunch Virginia Master Naturalist HSS

The name Quillworts kinda sounds like some medical condition that porcupines might get. Actually, Quillworts are primitive plants that most people know little or nothing about. If you open the book Flora of Virginia for vascular plants, you will notice that Quillworts are the very first plant listed. Vascular, means, the transportation of fluids by veins, thus segregating them from the mosses and liverworts which in their primitive state do not move fluids in this manner.

 Quillworts carry on their reproduction by spores, but in a different fashion than say the ferns. They produce 2 different types of spores. One of those spore types is called the megaspore. Very large as the name indicates and are female by their nature. The second type is the very tiny male spore. These are produced in a greater abundance as opposed to the megaspores. The mechanism to bring these two spore types together is water and when they do, what you get are not called seedlings as no seeds are involved, but rather sporelings.

The plants live in a small range of habitats, but all have water as their common denominator. Some species are wholly aquatic, remaining submerged throughout their life while other species grow in swamps, ditches, and such that become periodically submerged, but the soil always being wet if not in a flooded state.

They all have the same basic design, long linear leaves growing much like a clump of chives. Those leaves have a definitive trait like no other plant in that they are composed of 4 air chambers running longitudinally along inside the leaf. At short intervals, there are membranes that bisect the leaf that are reminiscent of the nodes in a bamboo cane. This serves as a supporting structure and also helps to allow the leaves to float off the bottom. The leaves have the habit of growing from the center outward and those outer leaves, being more mature in age, are the leaves that produce the spores. Generally toward the end of the summer, the bases of those leaves, in an alternating fashion, will produce the different female and male spores. These will become released, pair up, and produce new plants.

One interesting thing to note about these plants, they have a direct lineage back to the plants that helped to form the coal we use today. Those coal bearing relatives reproduced by spores as well, but in their case grew to be tree-like in form.