Tables: Master's thesis
Is there an answer to mapping old growth?
An examination of two projects conducted with remote sensing and GIS
Robert A. Norheim
Table 4-1
Comparison of the two old growth mapping projects and an earlier USFS inventory
The Wildeness Society "ancient forest" v. Pacific Meridian "old growth"(1000s of acres)
Pacific Wilderness
Meridian Society PMR Total
Forest Haynes "old "ancient / Forest
(USFS) growth" forest" TWS Acreage
Olympic 205 147.65 189.5 128% 651
Mt. Baker-Snoqualmie 433 725.28 585.7 81% 1,716
Gifford Pinchot 232 447.15 341.9 76% 1,331
Mt. Hood 218 363.25 334.5 92% 1,060
Willamette 338 783.55 605.0 77% 1,667
Umpqua 219 619.34 306.3 49% 988
Siuslaw 10 91.86 133.7 146% 625
Siskiyou 171 277.89 332.4 120% 1,093
Rogue River 50 267.95 150.1 56% 638
Total 3,858 3,723.92 2,979.1 * 80% 9,769
* Morrison also found 798,300 acres on the three forests in northern California, for an overall total of 3,777,400 acres of "ancient forest"
Sources: Haynes 1986, Pacific Meridian Resources 1991, Morrison et al. 1991
Table 5-1
Comparison between old-growth acreages in published reports and those calculated from datasets
(acres of ancient forest/old growth)
Forest Value in Value Not mapped Conver- Base for
published calculated by other sion comparison
report from data study change
The Wilderness Society
Olympic 189,500 196,745 -5,490 -20 191,235
MBS 585,700 586,132 -8,310 -97 577,725
Gifford 341,900 341,931 -50,552* 97 291,476
Pinchot
Mt. Hood 334,500 334,483 -103,240* 17 231,260
Total 1,451,600 1,459,291 -167,592 -3 1,291,696
Pacific Meridian Resources
Olympic 147,650 148,919 -640 -142 148,137
Mt. Baker- 725,280 720,260 -60,597† -26 622,338
Snoqualmie -37,299‡
Gifford 447,150 440,558 -350 -21 477,486
Pinchot +37,299‡
Mt. Hood 363,250 357,600 -346 25 357,279
Total 1,683,330 1,667,337 -61,933 -164 1,605,240
Notes: * East of Cascade crest; † Pasayten area; ‡ MBS lands administered by G. Pinchot
Sources: Pacific Meridian Resources 1991, Morrison et al. 1991
Table 5-2
Acreage differential as published and as corrected
(TWS ancient forest acreage vs. PMR old growth acreage)Forest Published Corrected Olympic 128% 129% Mt. Baker-Snoqualmie 81% 93% Gifford Pinchot 76% 61% Mt. Hood 92% 65% Total 86% 80%
Table 5-5
Confusion matrices
Pacific Meridian in rows, The Wilderness Society in columns(acres)
(a) Olympic National Forest
Low Other High Other
elevation ancient elevation than Total
old forest old ancient
growth growth forest
Low elevation old growth 64,474 26,112 9,489 38,267 138,341
% of array 10% 4% 2% 6% 22%
% of column 69% 35% 41% 9%
% of row 47% 19% 7% 28%
High elevation old growth 641 246 3,655 5,253 9,796
% of array 0% 0% 1% 1% 2%
% of column 1% 0% 16% 1%
% of row 7% 3% 37% 54%
Other than old growth 28,921 47,430 10,267 388,593 475,211
% of array 5% 8% 2% 62% 76%
% of column 31% 64% 44% 90%
% of row 6% 10% 2% 82%
Total 94,037 73,788 23,410 432,113 623,348
% of array 15% 12% 4% 69%
(b) Mt. Baker-Snoqualmie National Forest
Low Other High Other
elevation ancient elevation than Total
old forest old ancient
growth growth forest
Low elevation old growth 209,935 69,168 7,714 96,834 383,650
% of array 12% 4% 0% 6% 22%
% of column 71% 50% 5% 8%
% of row 55% 18% 2% 25%
High elevation old growth 6,689 4,371 108,664 118,964 238,689
% of array 0% 0% 6% 7% 14%
% of column 2% 3% 75% 10%
% of row 3% 2% 46% 50%
Other than old growth 77,428 64,574 29,182 932,192 1,103,376
% of array 4% 4% 2% 54% 64%
% of column 26% 47% 20% 81%
% of row 7% 6% 3% 84%
Total 294,052 138,113 145,559 1,147,990 1,725,715
% of array 17% 8% 8% 67%
(c) Gifford Pinchot National Forest
Low Other High Other
elevation ancient elevation than Total
old forest old ancient
growth growth forest
Low elevation old growth 88,584 64,197 6,165 198,312 357,258
% of array 8% 6% 1% 17% 31%
% of column 75% 70% 8% 23%
% of row 25% 18% 2% 56%
High elevation old growth 1,590 1,940 61,528 55,169 120,228
% of array 0% 0% 5% 5% 10%
% of column 1% 2% 75% 6%
% of row 1% 2% 51% 46%
Other than old growth 27,933 25,416 14,123 606,447 673,919
% of array 2% 2% 1% 53% 59%
% of column 24% 28% 17% 71%
% of row 4% 4% 2% 90%
Total 118,107 91,553 81,816 859,929 1,151,405
% of array 10% 8% 7% 75%
(d) Mt. Hood National Forest
Low Other High Other
elevation ancient elevation than Total
old forest old ancient
growth growth forest
Low elevation old growth 74,424 75,591 950 175,222 326,187
% of array 10% 11% 0% 25% 46%
% of column 71% 68% 6% 36%
% of row 23% 23% 0% 54%
High elevation old growth 208 208 11,382 19,295 31,093
% of array 0% 0% 2% 3% 4%
% of column 0% 0% 76% 4%
% of row 1% 1% 37% 62%
Other than old growth 29,994 35,810 2,694 288,768 357,266
% of array 4% 5% 0% 40% 50%
% of column 29% 32% 18% 60%
% of row 8% 10% 1% 81%
Total 104,625 111,609 15,026 483,285 714,545
% of array 15% 16% 2% 68%
Table 5-6
Agreement rates by Forest depending on PMR assignment of TWS "Other Ancient Forest"
(percent)"Other Ancient Forest" Olympic MBS Pinchot Mt. Hood counted as: Low elevation old growth 77.5 76.5 71.3 63.0 Low or high elevation old growth 77.5 76.7 71.5 63.0 Not old growth 80.9 76.2 67.9 57.4
Table 5-7
Aggregated confusion matrices
Pacific Meridian in rows, The Wilderness Society in columns(acres)
(a) Olympic National Forest
Ancient
Forest Other Total
Old Growth 104,617 43,520 148,137
% array total 17% 7%
% column total 55% 10%
% row total 71% 29%
Other 86,618 388,593 475,211
% array total 14% 62%
% column total 45% 90%
% row total 18% 82%
Total 191,235 432,113 623,348
(b) Mt. Baker-Snoqualmie National Forest
Ancient
Forest Other Total
Old Growth 406,540 215,798 622,338
% array total 24% 13%
% column total 70% 19%
% row total 65% 35%
Other 171,184 932,192 1,103,376
% array total 10% 54%
% column total 30% 81%
% row total 16% 84%
Total 577,725 1,147,990 1,725,715
(c) Gifford Pinchot National Forest
Ancient
Forest Other Total
Old Growth 224,004 253,481 477,486
% array total 19% 22%
% column total 76% 29%
% row total 47% 53%
Other 67,472 606,447 673,919
% array total 6% 53%
% column total 24% 71%
% row total 10% 90%
Total 291,476 859,929 1,151,405
(d) Mt. Hood National Forest
Ancient
Forest Other Total
Old Growth 162,762 194,517 357,279
% array total 23% 27%
% column total 70% 40%
% row total 46% 54%
Other 68,498 288,768 357,266
% array total 10% 40%
% column total 30% 60%
% row total 19% 81%
Total 231,260 483,285 714,545