LaMotte Water & Soil pH - Manual (Page 12)

FUNGUS: A primitive group of plants characterized by the absence of
chlorophyll; includes mushrooms, molds, mildews, rusts and smuts which
live primarily on dead or living organic matter.
HUMUS: Well decomposed vegetable and animal material in the soil
which is capable of holding large amounts of plant nutrients and water.
HYDROXYL ION: A negatively charged particle (OH
_
) containing
oxygen and hydrogen. Hydroxyl ions raise pH.
HYDROGEN ION: A positively charged particle (H
+ ) containing only
hydrogen. Hydrogen ions lower pH.
INDICATOR: A chemical reagent added to a test sample which causes a
color change.
INDICATOR SOLUTION: A liquid reagent added to a test sample to
cause a color change.
ION: An electrically charged particle.
LEACHING EFFECT: The removal of dissolved chemical compounds
from the soil by passing water through it.
LEAF MARGIN: The border or edge of a leaf. A leaf margin may appear
smooth, saw-like, or tooth-like.
LITMUS PAPER: Paper used to determine pH. When dipped in a
solution litmus paper turns blue if the solution is alkaline, pink if it is
acidic.
LOAM: Soil which contains sand, silt, and clay. Soils that are
predominantly sand but contain some silt and clay are called sandy loams.
Soils that are predominantly clay but contain sand and silt are called clay
loams.
MACRONUTRIENT: Those nutrients which the plants require in large
quantities. The macronutrients are nitrogen, phosphorus, potassium,
calcium, magnesium, and sulfur.
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