Umpqua Watersheds
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Glossary
Glossary

Abbreviations


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

  Glossary   P

Parent material
The mineral or organic matter from which the upper layers of soil are formed.
Park-like structure
Stands with large scattered trees and open growing conditions, usually maintained by natural ground fires.
Partial retention
A tree harvest method that removes only part of the stand. (See High Grading.)
Peak Flow
The highest amount of stream of river flow occurring in a year, or from a single storm event.
Percolation
Downward flow or infiltration of water through the pores or spaces of rock or soil.
Perennial stream
A stream that flows throughout the year and from source to mouth.
Personal use
The use of a forest product, such as firewood, for home use and not for commercial use.
Planning area
The area of National Forest land covered by a Regional Guide or Forest Plan.
Planning period
The 50 year time frame for which goods, services, and effects were projected in the development of the Forest Plan.
Pole/sapling
The stage of forest succession in which trees are between 3 and 7 inches in diameter and are the dominant vegetation.
Pole timber
Trees at least 5 inches in diameter, but smaller than the minimum size for sawtimber.
Precommercial thinning
Removing some of the trees from a stand that are too small to be sold for lumber or house logs, so the remaining trees will grow faster.
Prescribed fire
Fire set intentionally in wildland fuels under prescribed conditions and circumstances. Prescribed fire should be used to mitigate the suppression of natural fires.
Prescription
Management practices selected to accomplish specific land and resource management objectives.
Prognosis
A computer model for timber growth and yield. It projects per-acre growth and volume yield for commercial timber stands.
Public domain lands
The territory ceded to the Federal government by the original thirteen states, plus additions by treaty, cession, purchase and theft.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z