LaMotte Soil Texture - Manual (Page 7)

GLOSSARY OF TERMS
ABSORB -
To take a substance into the physical structure of a liquid or
solid without chemical reaction.
AVAILABILITY
- Nutrients in solution which are capable of being
used by the plant.
BACTERIA -
Microscopic single-celled organisms which are helpful in
increasing soil fertility. They break down complex substances, fertilizer,
and vegetable matter in the soil by decay and convert these substances
to simpler forms which can be used by plants.
CLAY -
The smallest particle size in soil; has the tendency to become
sticky or greasy to the touch when wet. When clay becomes dry it is
extremely hard and brick-like.
FUNGUS -
A primitive group of plants characterized chiefly by the
absence of chlorophyll; includes mushrooms, molds, mildews, rusts and
smuts which live primarily on dead or living organic matter.
HUMUS -
The well decomposed vegetable and animal material in the
soil which is capable of holding large amounts of plant nutrients and
moisture.
LEAF MARGIN -
The border or edge on a leaf. A leaf margin may
take many shapes or forms such as smooth, saw-like, or tooth-like.
MINERAL DEFICIENCY DISEASE -
A disease in plants which is
caused by the lack of one or more of the important plant nutrients.
MINERAL SOIL -
A general term used for a soil composed chiefly of
inorganic matter, in contrast to an organic soil which is composed
chiefly of organic matter.
ORGANIC MATTER
- The fraction of soils which result from the
decomposition of plant and animal matter through the action of
micro-organisms. Organic matter in soils can be increased by the
addition of manure, compost, and peat moss. Soils which are rich in
organic matter have a high water holding capacity and are usually well
aerated. (See humus)
pH -
A measurement based on the number of hydrogen ions in a
substance. A pH scale is used to determine whether a substance is acid,
basic, or neutral. On a pH scale the midpoint is 7.0 indicating a neutral
substance; readings below 7.0 are acidic; readings above 7.0 are basic.
ROOT HAIRS
- Very small roots of a plant which take in nutrients
from the soil solution.
SAND -
Small rock fragments that make up the mineral portion of the
soil. Sands represent the largest particle size in textural classification
and are formed through erosion of native rock material.
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