Plant Leaves Left On Soil
Many plants produce organic acids. Where plant litter accumulates on or is incorporated to the soil, these acids (including acetic acid, humic acid (see http://www.suprahumic.unina.it/), oxalic acid, and tannic acid) are liberated. This is especially acute in soils under coniferous trees such as pine, spruce and fir, which return fewer base cations to the soil than do most deciduous trees.
Read more about this topic: Soil Acidification
Famous quotes containing the words plant, leaves, left and/or soil:
“When they turn the sun
on again I’ll plant children
under it, I’ll light up my soul
with a match and let it sing....”
—Anne Sexton (1928–1974)
“We say ourselves fortunate to be driving by today.
That we may look at them, in their gardens where
The summer ripeness rots. But not raggedly.
Even the leaves fall down in lovelier patterns here.”
—Gwendolyn Brooks (b. 1917)
“Someone had literally run to earth
In an old cellar hole in a byroad
The origin of all the family there.
Thence they were sprung, so numerous a tribe
That now not all the houses left in town
Made shift to shelter them without the help
Of here and there a tent in grove and orchard.”
—Robert Frost (1874–1963)
“The civilized nations—Greece, Rome, England—have been sustained by the primitive forests which anciently rotted where they stand. They survive as long as the soil is not exhausted. Alas for human culture! little is to be expected of a nation, when the vegetable mould is exhausted, and it is compelled to make manure of the bones of its fathers. There the poet sustains himself merely by his own superfluous fat, and the philosopher comes down on his marrow-bones.”
—Henry David Thoreau (1817–1862)