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FOREST FIRES & FIRE ECOLOGY
The nature of forest fires, how they are fought and the necessary role played by fire in maintaining certain ecosystems. 2 slide programs and texts. 40 slides.
EP #170X SLIDES
$72.50

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SAVE OVER $12.00 ON 2 SLIDE SET BUNDLE ORDER EP #170X.............$72.50
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FOREST FIRE Order #170..........$42.50

A forest fire from the beginning--how it starts, is fought and controlled. Very
dramatic pictures from up close: the fire line, air drops, radio communication, bulldozers,
ground crew. Text discusses the drama of the fire itself and its aftermath. 20 slides and
guide.

CONTENT SAMPLE: 13430 How can such a fire be stopped? By clearing a path all
around the burning area, a fireline or firebreak, so wide that the flames cannot leap across. When
the terrain permits, bulldozers can be used to cut the fireline. Using both their front blades and
sodbusters on the rear, they scrape a wide path right down to bare earth, pushing trees, brush,
and humus aside, destroying some trees in order to save many more.

Backfires are also used frequently. This involves setting a controlled fire in a strip ahead
of the wildfire. The inrush of air to the forest fire pulls the flames from the backfire toward it,
leaving a burned out area with no available fuel ahead of the main fire. Because backfires are not
as hot as the main fire, they serve to burn off the debris and brush that would provide tinder, while
not igniting the large trees.

It is important to build the fireline sufficiently far ahead of the fire to allow time to
complete it before the fire reaches it, otherwise the fire cannot be contained and will jump the
proposed line. On the other hand, everything enclosed within the fireline is abandoned to the
flames and will be lost, so the enclosed area must be kept as small as is practical.

REVIEWS: "...a good...look at a real forest fire." Bay Area Media Evaluation Guild.
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INTRODUCTION TO FIRE ECOLOGY Order #126..........$42.50

This program sheds new light on the role of fire. For a long time we have been
taught to think of wildfire as uniformly bad--Smoky the Bear drilled his message home.
Now we are learning that fire plays an important part in maintaining a number of
ecosystems and that a number of plants are specially adapted to fire and need it in order
to reproduce. Many animals including quite small ones not only survive forest fires, but
benefit from them. 20 slides and guide.

CONTENT SAMPLE: 25595 Soils are the foundation of terrestrial ecosystems. Is this
foundation weakened when burned? Very often fire has a beneficial effect upon soils, particularly
when the fire is light to moderate in intensity and rather swift. The organic litter on the soil surface
in such fires is usually not completely consumed and the underground roots of many perennial
plants are not killed, insulated as they are from the heat of the fire by the soil. The remaining
organic litter protects the soil surface and the roots often quickly re-sprout. Burning increases the
availability of calcium, potassium, phosphorous and trace minerals in the soil. The availability of
nitrogen also usually increases, however the total amount of nitrogen present may be reduced.
Further, the pH of burned soils is usually increased--that is, the acidity is reduced. The impor-
tance of this effect is that the microorganisms that are so important to the operation of soils
become more abundant and active in less acidic soils. This is especially important in high
northern latitudes where soils are usually excessively acid and the decay of organic matter is
therefore very slow due to low microbe activity. Moderate fires are a major source of nutrient
release and are usually very beneficial. However, a very hot burn can cause extreme depletion of
nutrients and organic material, leaving a dead, nutrient poor soil upon which plant recovery is
retarded.

REVIEWS: "Excellent visuals...enlightening...recommended." Booklist. "...good
introductory material...recommended." School Library Journal.
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~1875-039~ Fire in chaparral. photo by Redwood Edugraphics.

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