Inventory Summary for Region 3 Arizona National Forests
 
Interior West Forest Inventory and Analysis (IWFIA) Program
USDA Forest Service, Rocky Mountain Research Station, Ogden, Utah
This reference is based on Region 3 Arizona National Forest inventories conducted from 1995 to 1998. National Forests are inventoried according to administrative boundaries.
Refer to terminology and field manual for supplemental documentation and term definitions.
                   
 
     Number of field plots* and (condition proportions)** sampled by land type:  Number of field plots*** not sampled:  
               
        Forest and   Denied    
  National Forest Survey Date**** Forest Nonforest Nonforest Inaccessible access Other Total
    279 35 10 2 0 0 326
  Apache-Sitgreaves 1996-1997 (285.9) (38.1) -- -- -- -- (324.0)
  (1996) (t=151.7; w=134.2) -- -- -- -- -- (285.9)  
    233 37 22 9 0 0 301
  Coconino 1995-1996 (247.7) (44.3) -- -- -- -- (292.0)
  (1995) (t=131.5; w=116.2) -- -- -- -- -- (247.7)
    202 42 36 2 0 0 282
  Coronado***** 1996-1998 (224.2) (55.8) -- -- -- -- (280.0)
  (1997) (t=10.2; w=214.0) -- -- -- -- -- (224.2)
    195 34 15 3 0 0 247
  Kaibab 1995-1997 (208.0) (36.0) -- -- -- -- (244.0)
  (1995) (t=85.3; w=122.7) -- -- -- -- -- (208.0)
    105 76 10 2 0 0 193
  Prescott 1995-1996 (112.4) (78.6) -- -- -- -- (191.0)
  (1996) (t=9.4; w=103.0) -- -- -- -- -- (112.4)
    216 213 26 9 0 0 464
  Tonto 1996-1998 (229.0) (226.0) -- -- -- -- (455.0)
  (1996) (t=31.7; w=197.3) -- -- -- -- -- (229.0)
* Field plot or location (also referred to as sample site): An area containing the field location center and all sample points, distributed over an area approximately 2.5 acres in size. A field location
layout consists of four fixed-radius subplots (1/24 acre; 24.0-foot radius) for sampling trees and understory vegetation, and four microplots (1/300 acre; 6.8-foot radius) for sampling seedlings
and saplings. At each sample site, distinct conditions of forest land and nonforest land meeting minimum size requirements are identified. Forest land is divided into timberland and woodland
and can be further divided into smaller conditions if variations exist in any of the following defining attributes: forest type, stand size, stand origin, and stand density. All conditions, including
finer divisions of conditions, must meet minimum size requirements. A field plot is sampled (established and measured) if any portion of the four subplots occurs within a sampled forest land
condition class. Each subplot/microplot area is mapped to identify distinct condition classes. Whole plots are totaled by land type accordingly: "Forest"- plots that sampled only forest conditions,
"Nonforest"- plots that sampled only nonforest conditions, "Forest and Nonforest"- plots that sampled both forest and nonforest conditions. Nonforest land includes water.
** Condition proportions are the fraction of plot area sampled on each condition. The sum of all condition proportions for a plot equals 1.00. The numbers in parenthesis are the sum of all the
condition proportions by land type (forest or nonforest). Forest land is further divided into timberland (t) and woodland (w). Nonforest land includes water.
*** Only includes whole field plots where all four subplots are in a nonsampled category. Plots that are partially nonsampled are absorbed into the sampled forest and nonforest categories.
 
**** National Forests were inventoried over a 2 to 3 year period. The survey date listed in parentheses has been selected as the representative inventory year (this year indicates when the majority
of sample sites were inventoried). 
***** The Coronado NF resides in Arizona and New Mexico. An additional 10 locations, included above, are located on the New Mexico portion of the Coronado NF.