Forests and Timber >
Site Prep > Prescribed Burning
How many of us have worked on a slash-piling
crew, piling the slash into piles to be burned after the
first rains fall? How many of us have lugged a drip-torch
down a burn unit, burning the slash where it fell? Burning
is called "prescribed burning" because it is a
tool that foresters use on certain areas of land for many
reasons, including preparation for planting like medicine
prescribed from a doctor.
|| Foresters use burning as a management
tool, since fire is nature's principal way of preparing
Oregon's forest for a new stand. Many of Oregon's timber
trees, like Douglas-fir and ponderosa pine, owe their
dominance in Oregon's forests to fire. They have evolved
to be tolerant of occasional fires and will out-compete
other tree species as a result.
Burning is common on logged units awaiting
reforestation because it clears the soil for reseeding or
tree planting. It is also popular because it clears ground
on steep areas where machines can't weed or expose the soil,
and it produces large, easily planted areas without large
machines that may compact the soil; and fire costs less.
There are tradeoffs: when the slash
isn't removed some animals that damage trees, like the woodrat,
mountain beaver, and porcupine, can use slash as hiding
cover, avoiding predation and having easy access to nearby
seedlings. However, when burning is used to remove the slash,
it also clears the way for the regeneration of certain plants
that are good forage for browsing animals like deer and
elk, attracting these animals that may end up nibbling on
the new trees as well!
Unfortunately, while fire is an inexpensive
tool, controlling these fires can be expensive. Also, the
smoke produced from these fires can occasionally be a nuisance
for people living nearby. Finally, burning the slash also
results in the loss of some soil nutrients. For these reasons,
other ways of site preparation are used when burning isn't
the best method for preparing the unit.