Saplings from nurseries have well-developed secondary roots, which spread laterally through the ground.
These secondary roots further produce their own smaller lateral roots (tertiary roots).
From the taproot are produced smaller lateral roots (secondary roots) that grow horizontally or diagonally.
From the taproot arise smaller lateral roots (secondary roots), which in turn produce even smaller lateral roots (tertiary roots).
In late fall or early spring, just plant a few finger-thick secondary roots, called sets, which are sold ready to plant.
The taproots, larger secondary roots, and, in some cases, underground stems, have contractile elements in the pith and cortex that draw the stem more deeply into the ground.
In some cases, the taproot system is modified into a fibrous, or diffuse, system, in which the initial secondary roots soon equal or exceed the primary root in size.
A taproot system is one in which the primary root remains the largest, and a number of smaller secondary roots are formed from it; taproots are found in such plants as carrots and dandelions.
Cycad seedlings initially form a stout, fleshy taproot that persists in subterranean forms for many years but is augmented by secondary roots which also are quite thick and fleshy.
The system may be modified into a fibrous, or diffuse, system, in which the initial secondary roots soon equal or exceed the primary root in size and there is no well-defined single taproot.
Water limitation did not affect the topology of secondary roots colonising the soil.
