Generalities Sparganium erectum
The Biodo or major knife is a perennial rhizomatous aquatic plant, native to the wetlands of the European continent. The fleshy rhizomatous roots sink on the bottoms of small ponds or slow streams, are submerged and floating in the water, and from them stems upright, light green stems, covered with large leaves of the same color, arranged in a fan , broad, leathery, which constitute dense tufts that reach dimensions even greater than one meter in height.
The stems of this aquatic plant can reach a height of between 40 and 80 centimeters.
As for the flowering of this plant, throughout the summer they produce long stems that carry particular highly branched inflorescences, consisting of bunches of round, greenish-white glomeruli, the upper male ones, the lower female ones. The fruits are succeeded by the flowers, small rounded berries gathered in tufts.
Its scientific name is Sparganium erectum and is part of the Sparganiaceae family which has about ten species in Italy, present spontaneously. However, there are other varieties of Sparganium such as angustifolium and natans, always spontaneous and present in Italy as spontaneous.
The biodo is a plant that prefers sunny positions, but develops without problems even in partial shade; it doesn't fear cold weather, and usually you can see it even in the wild state in the waterways of our country. It should be planted on the banks of slow streams or small ponds, taking care to position the rhizomes at a depth equal to their diameter, in fairly fertile and loose soil, in a place that is completely submerged by the water.
Sparganium erectum plants can be found in many areas of our country, always being close to ponds and ditches. From the plains up to 500 meters above sea level, the major cutlery plants effectively colonize many river areas exposed to the sun, and in some stretches, such as coastal areas and areas mitigated by alpine lakes, it is possible to find greater cutlery species even beyond the 1000 meters of altitude.