Andisols are a soil order formed from volcanic ash and cinder deposits. They largely consist of non-crystalline minerals like allophone and imogolite that form strong bonds with organic matter. Andisols are typically light, fluffy soils that hold a lot of water like a sponge. While fertile soils when not highly weathered, volcanic soils can complex with phosphorus and require additions of organic matter, lime or fertilizer to maintain fertility.

1. By_ Sakil Ahmed
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2. Introduction
According to The USDA system of
Soil Taxonomy Twelve soil soil orders
are recognized. Andisols is one of
them.
Globally, Andisols are the least
extensive soil order and only account
for >1% of the ice-free land area.
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3. Parent materials
Andisols, also known asVolcanic
soils, are formed from volcanic ash and
cinder deposits.
Most of the world’s volcanic soils are
not highly weathered.
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4. Mineralogy
 Volcanic soils largely consist of non-
crystalline minerals, such as allophone and
imogolite.
 These minerals form strong bonds with
organic matter. As a result, organic matter
generally accumulates in the surface
horizon.
 In addition to organic matter, volcanic soils
may also contain high amounts of volcanic
glass material with the possibility of
amorphous iron and aluminum minerals.
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5. Physical Traits
Andisols are usually light.
 Fluffy and are easily tilled.
Like a sponge
 These soils also hold a lot of water.
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6. Fertility
 When not highly weathered, volcanic soils
are typically very fertile soils. However,
volcanic soils form strong complexes with
phosphorus.
 When poorly managed, phosphorus can be
limiting.
 Fertility problems may be corrected with
additions of organic matter, lime and/or
fertilizer amendments.
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