Taproot
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This article is about plant biology. For information on the Nu Metal band click here.
A plant's taproot is a straight tapering root that grows vertically down. It forms a center from which other roots sprout.
Plants with taproots are difficult to transplant.
The taproot is why dandelions are hard to uproot — the top is pulled, but the long taproot stays in the ground, and re-sprouts.
A taproot system contrasts to a fibrous root system, with many branched roots.
Most trees begin life with a taproot, but after one to a few years change to a wide-spreading fibrous root system with mainly horizontal surface roots and only a few vertical, deep anchoring roots. A typical mature tree 30-50 m tall has a root system that extends horizontally in all directions as far as the tree is tall or more, but well over 95% of the roots are in the top 50 cm depth of soil.
Many taproots are modified to become storage organs.
Some plants with taproots:
Typical taproots
- conical root : another word for taproot.
- fusiform root : tapers at the top and at the bottom, e.g. the taproot of a white radish.
- napiform root : is broader than it is long, e.g. the root of a turnip.
External links and references
- One reference at Ohio State (http://www.hcs.ohio-state.edu/mg/manual/botany.htm)
- Fullerton Arboretum on taproots (http://www.arboretum.fullerton.edu/grow/taproot.asp)