The rod that grows in the middle of the leek is called leek moss. There are 2 kinds of leek stems, one is the flowering stem that grows above ground, and one is the nutritive stem that grows underground. Flowering stem in the reproductive growth stage of leeks, the top bud of the stem disk develops into flower buds, draw flower shoots (also called leek shoots). Flowering stems are about 50 centimeters tall, with involucral bracts at the top of the flowering shoots, and flowering organs inside the involucral bracts. Flowering stem is the leek plant for its flower and fruit development to transport nutrients through the channel. Nutritional stem flattened round daisy, is the top bearing leaf sheaths, around the root system of the flattened disc-shaped stems, known as the "stem disk". The terminal buds are surrounded by the lower part of the leaf sheaths, so they do not freeze to death in winter. The upper part of the stem disk is leafy, and the lower part is rooted, with the increase of plant age and tillering year by year, the nutritive stem is constantly extended to the ground into a fork-like branch, so it is also known as the "rhizome". Nutrient stem is the new leek roots, new leaves and tillers of the meristematic organization, but also an important organ of the leek storage nutrients in winter

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