A root crown, also known as the root collar or root neck, is that part of a
root
In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the sur ...
system from which a stem arises. Since roots and stems have quite different
vascular
Blood vessels are the structures of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away from ...
anatomies, major vascular changes take place at this point.
Root-crown temperature has been found to affect plant growth and physiology in a number of ways.
Root crowns need to be exposed and 'breathe'; this is one way that some plants take in oxygen.
A number of pests and diseases affect specifically this part of the plant, including
root-crown rot (or root-crown fungus) and a number of species of
root-crown weevil.
The root crown area usually appears swollen, tapered, constricted or very thin - as well as a combination of these. The area of the root crown is usually located around or at the soil level and can be vaguely or clearly apparent.
References
Plant roots
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