| Tower Site | Importance Value |
|---|---|
| Wind River Crane Site | 11.0956 |
| Florida-Kennedy Space Flight Center (scrub oak) | 10.3324 |
| Fir site | 9.5777 |
| Univ. of Mich. Biological Station | 8.7099 |
| Blodgett Forest | 6.6504 |
| Vaira Ranch | 6.1349 |
| Tonzi Ranch | 6.1349 |
| Sky Oaks Biological Station | 5.7295 |
| Florida-Kennedy Space Flight Center (slash pine) | 5.6014 |
| Gainesville (Donaldson) - slash pine (mid-rotation) | 5.5743 |
| Jasper Ridge | 5.3848 |
| Gainesville (Austin Cary) - 65yr naturally regenerated slash/longleaf pine | 5.3366 |
| Niwot Ridge Forest (2) | 5.2837 |
| Niwot Ridge Forest | 5.2837 |
| Glacier Lake | 5.2837 |
| Metolius - new young pine | 4.7200 |
| Metolius - intermediate (69 yrs) ponderosa pine | 4.7200 |
| Metolius - Eyerly burn | 4.7200 |
| Canaan Valley | 4.7200 |
| Cedar Bridge | 4.6700 |
| Black Hills | 4.4664 |
| Little Prospect Hill | 4.1752 |
| Howland Forest (west tower) | 4.1752 |
| Howland Forest (main tower) | 4.1752 |
| Howland Forest (harvest site) | 4.1752 |
| Harvard Forest hemlock site | 4.1752 |
| Harvard Forest Main Tower | 4.1752 |
| Willow Creek | 4.1591 |
| Sylvania Wilderness Area (Watersmeet) | 4.1591 |
| Park Falls/WLEF | 4.1591 |
| Lost Creek | 4.1591 |
| Morgan Monroe State Forest | 4.1487 |
| Santa Rita Mesquite | 4.0913 |
| Rosemount | 3.9293 |
| Bondville (companion site) | 3.9293 |
| Bondville | 3.9293 |
| Northern Michigan Jack Pine Stand | 3.7999 |
| Great Mountain Forest | 3.6044 |
| Valles Caldera National Preserve | 3.3144 |
| Audubon Research Ranch | 3.3144 |
| Cub Hill (Baltimore) | 3.2368 |
| Utah Juniper woodland | 3.1616 |
| Utah Crested wheatgrass | 3.1616 |
| Missouri Ozark Site | 3.0796 |
| Goodwin Creek | 3.0796 |
| Utah Sagebrush | 3.0644 |
| Walker Branch Watershed | 3.0544 |
| Duke Forest - loblolly pine | 3.0544 |
| Duke Forest-open field | 3.0544 |
| Duke Forest-hardwoods | 3.0544 |
| Chestnut Ridge | 3.0544 |
| CRP ungrazed | 2.9481 |
| CRP minimum-till | 2.9481 |
| CRP grazed | 2.9481 |
| Walnut River Watershed | 2.9479 |
| Rannells Ranch (ungrazed) | 2.9479 |
| Rannells Ranch (grazed) | 2.9479 |
| Manhattan (cedar forest 30 km N) | 2.9479 |
| Konza Prairie LTER | 2.9479 |
| J-17 Savanna | 2.9479 |
| Freeman Ranch Woodland | 2.9479 |
| Freeman Ranch Transition | 2.9479 |
| Freeman Ranch Grassland | 2.9479 |
| Fort Peck | 2.8361 |
| SGP Lamont ARM site | 2.6792 |
| Mead - rainfed site | 2.6792 |
| Mead - irrigated site | 2.6792 |
| Mead - irrigated/rotation site | 2.6792 |
| Brookings | 2.6746 |