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Honeybees are important players in production
agriculture because of their role in pollinating crops.
Pollination is the process where pollen is transferred from
the anthers (male flower parts ) to the stigma (female
flower parts). Some plants are self-fertile and do not
require an external agent such as wind or insects to
perform this process. Other plants may be self-infertile,
thus requiring active transfer of pollen from one flower to
another. When environmental conditions are favorable,
pollen, transferred to the stigma, germinates and sends a
pollen tube bearing the tube nucleus and sperm nuclei
down through the style into the ovary and finally to the
ovule. Fertilization occurs when the sperm nuclei fuses
with the female egg nucleus. This fusion results in a
fertilized egg and leads the development of a viable seed.
It has been estimated that approximately one-third of
our total diet is based upon insect-pollinated plants.
Given the importance of bees in agricultural, they must be
protected from accidental poisoning from pesticides.
Most bee poisoning occurs when the bees are foraging
flowers to collect pollen and nectar. Foraging bees can be
hit directly by a spray or pick it up as a residue on the
plant surface or in contaminated water. In some cases, the
insecticide is fast-acting and results in the death of the bee
before it can return to the hive. In other instances, the
poison can be brought back to the hive as contaminated
nectar, pollen, or water. This can result in severe
poisoning if fed to the developing brood and sometimes
causes complete destruction or weakening of the colony.
Some insecticides are toxic to bees and certain
precautions must be made during application when
indicated on the label. One insecticide, Penncap-M, can
be especially toxic to bees if applications are not made in
accordance to the label. This product is a flowable
formulation consisting of water suspension of polymeric-
type microcapsules which contain methyl parathion. Bees
can pick up this material when foraging flowers and bring
it back to the hive. Bees are then killed when they ingest
contaminated pollen. In order to avoid this problem,
Penncap-M MUST NOTbe applied whenever there
are blooming plants (including weeds) in or
surrounding orchards irregardless of whether bees
are present or not. In addition, the Rutgers University
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1998 Commercial Tree Fruit Production Guide contains
statements indi cati ng t hatno i nsect ici de s houl dbe
us edduri ng bl oom .
Groundwater is the water contained below our soils
and is used by 90% of the rural population in the U.S. as
their sole source of drinking water. Contamination by
pesticides and other pollutants of this supply is becoming
a serious problem. One source of contamination has been
shown to be agricultural practices. Protection of our
groundwater by agriculture is essential.
Groundwater collects under our soils in zones called
aquifers. These zones are comprised of layers of sand,
gravel or fractured bedrock, which, by their nature, hold
water. The water in aquifers comes from rainfall,
snowfall, etc., which moves down through the soil layers
to the aquifer. The depth of the aquifer below the surface
depends on many factors. Where it is shallow, we see
lakes, ponds and wetlands. We refer to these areas as
having a shallow water table. In areas where it is deep,
we find arid regions.
Factors That Affect Movement of Water
and Contaminants
The depth of these zones, in conjunction with soil
types, influences how much surface water reaches the
aquifer. Their depth also affects how quickly water and
contaminants reach an aquifer. Thus, shallow water tables
tend to be more vulnerable to contamination than deeper
ones.
This tendency, however, depends on the soil type.
Soils with high clay or organic matter contents may hold
water longer and retard its movement to the aquifer.
Conversely, sandy soils allow water to move downward
at a fast rate. High levels of clay and/or organic content in
soils also provide a large surface area for binding
contaminants, which can slow their movement into
groundwater. Soil texture also influences downward water
movement. Finer textured soils have fewer spaces
between particles than coarse ones thus, decreasing
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