Growing Poplar and Willow Trees on Farms, National - FAO

What about roots thicker than 10 mm
Roots more than 10 mm diameter contributed only 5% of the root length, so
are very thinly dispersed around the tree.
When the fine roots die the water supply to the rest of the tree ceases. Cells
lose water <strong>and</strong> die. The dead roots quickly dry out <strong>and</strong> become brittle, <strong>and</strong>
lose their strength to resist any soil deformation. They do not bind soil
particles in the way that fine roots do.
In summary:
• The roots of poisoned poplar trees deteriorated very quickly <strong>and</strong> lost
any capacity to bind soil particles <strong>and</strong> stabilise slopes within a year.
• Within a year a poisoned tree functions like a bare slope, except
within 2 m of the trunk where the bulk of large roots will provide
some resistance to soil movement.
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