root crown

{{Short description|Intersection between the root and the stem}}

A root crown, also known as the root collar or root neck, is that part of a root system from which a stem arises. Since roots and stems have quite different vascular 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.{{cite journal | author = Schwarz, Meier | year = 1972 | title = Influence of root crown temperature on plant development | journal = Plant and Soil | volume = 37 | issue = 2 | pages = 435–439 | doi = 10.1007/BF02139988| bibcode = 1972PlSoi..37..435S | s2cid = 420759 }} 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)[https://pddc.wisc.edu//wp-content/blogs.dir/39/files/Fact_Sheets/FC_PDF/Root_and_Crown_Rots.pdf Root and Crown Rots]. University of Wisconsin Garden Facts. 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.{{Cite web|url=http://www.cactus-art.biz/note-book/Dictionary/Dictionary_R/dictionary_root_crown.htm|title = Root crown}}