**[Table 1]{.underline}**

**NALCC^1^**

[Landcover %Land Area BVOC^2^]{.underline}

Mixed forest 1.2 100.96

Conifer forest 1.9 63.25

Deciduous forest [78.4 6718.46]{.underline}

**Total 81.6 6882.67**

**NLCD^3^**

[Landcover %Land Area BVOC^2^]{.underline}

Evergreen forest 2.9 380.67

Mixed forest/ 8.4 697.86

Non-natural woody

Deciduous forest [42.5 3644.62]{.underline}

**Total 53.8 4983.67**

**Forest Inventory and Analysis (FIA)^1^**

[Landcover %Land Area BVOC^2^]{.underline}

Red Maple 1.1 20.10

Chinkapin Oak 1.1 615.08

Black Walnut 1.2 31.05

Hackberry 1.2 10.19

Yellow Poplar 1.3 11.09

Black Oak 1.6 859.78

Chestnut Oak 1.6 886.94

Northern Red Oak 1.7 951.64

Eastern redcedar 1.7 36.67

Sassafras 1.8 14.43

American Beech 1.9 21.90

White Ash 2.0 16.35

Sugar Maple 2.3 42.20

Flowering Dogwood 2.9 51.56

White Oak 3.9 2165.84

American Elm 4.0 31.13

Shagbark Hickory 5.3 97.53

Other^4^ [10.1 2267.23]{.underline}

**Total 46.7 8121.79**

^1^See Table 2

^2^BVOC - Biogenic Volatile Organic Compounds

^3^ http://landcover.usgs.gov/natllandcover.asp

^4^ Individually less than 1% of total land

**[Table 2]{.underline}**

+-----------------------------------+-----------------------------------+
| **Description of raw data**       | **BELD3 class**                   |
+-----------------------------------+-----------------------------------+
| USGS North American Land          | Water, default landcover          |
| Characteristics Database(NALCC):  | classifications^\*^               |
| (AVHRR 1992-1993) 1-km classified |                                   |
| pixels for North America^\*^      | Urban area                        |
|                                   |                                   |
| U.S. Department of Commerce,      | Total forest area                 |
| Bureau of Census: Urbanized area  |                                   |
| boundaries 1990                   | Total agricultural area, area by  |
|                                   | crop type                         |
| USDA, U.S. Forest Service, Forest |                                   |
| density database, Zhu and Evans   | Forest crown cover percentages by |
| (1994). A 1-km                    | species                           |
|                                   |                                   |
| dataset of estimated percent tree |                                   |
| cover for the conterminous U.S.   |                                   |
|                                   |                                   |
| U.S. Department of Agriculture,   |                                   |
| National Agricultural Statistics  |                                   |
| Service: 2002 Census of           |                                   |
| Agriculture                       |                                   |
|                                   |                                   |
| U.S. Forest Service, Eastwide and |                                   |
| Westwide Forest Inventory         |                                   |
| Analysis (FIA). Contains 0.4-ha   |                                   |
| surveys of nearly 400,000 plots   |                                   |
| in the conterminous U.S.          |                                   |
| Allometric equations use          |                                   |
| diameter-at-breast-height         |                                   |
| measurements to estimate crown    |                                   |
| cover by species                  |                                   |
+-----------------------------------+-----------------------------------+

^\*^ NALCC classifications (modified Level 2): urban and built-up land,
evergreen broadleaf forest, dryland cropland and pasture, evergreen
needleleaf forest, irrigated cropland and pasture, mixed forest, mixed
dryland/irrigated cropland and pasture, water bodies, cropland/grassland
mosaic, herbaceous wetland, cropland/woodland mosaic, wooded wetland,
grassland, barren or sparsely vegetated, shrubland, herbaceous tundra,
mixed shrubland/grassland, wooded tundra, savanna, mixed tundra,
deciduous broadleaf forest, bare ground tundra, deciduous needleleaf
forest, snow or ice.

**[Table 3]{.underline}**

+-----------------------+---------------+------------------------------+
| Landcover             | Area (ha)     | Percent Landcover            |
+-----------------------+---------------+------------------------------+
| a\) Forest^1^         | 231,887,656   | 31                           |
|                       |               |                              |
| [Top ten              | 14,474,207    | 1.9                          |
| species]{.underline}  |               |                              |
|                       | 10,782,619    | 1.4                          |
| *Pseudotsuga          |               |                              |
| menziesii*            | 10,280,124    | 1.4                          |
|                       |               |                              |
| *Pinus taeda*         | 10,143,189    | 1.4                          |
|                       |               |                              |
| *Juniperous           | 8,899,037     | 1.2                          |
| virginiana*           |               |                              |
|                       | 7,847,909     | 1.0                          |
| *Populous             |               |                              |
| grandidentata*        | 7,700,162     | 1.0                          |
|                       |               |                              |
| *Pinus ponderosa*     | 7,466,187     | 1.0                          |
|                       |               |                              |
| *Ulmus americana*     | 7,374,218     | 1.0                          |
|                       |               |                              |
| *Acer rubrum*         | 5,446,535     | 0.7                          |
|                       |               |                              |
| *Carya ovat*a         | 175,078,340   | 23                           |
|                       |               |                              |
| *Quercus alba*        | 60,944,421    | 8.0                          |
|                       |               |                              |
| *Pinus contorta*      | 30,532,558    | 3.1                          |
|                       |               |                              |
| b\) Agriculture^2^    | 23,826,566    | 3.1                          |
|                       |               |                              |
| [Top ten crop         | 22,543,401    | 3.0                          |
| types]{.underline}    |               |                              |
|                       | 20,394,372    | 2.7                          |
| Miscellaneous crop    |               |                              |
|                       | 4,373,341     | 0.6                          |
| Corn                  |               |                              |
|                       | 4,349,548     | 0.6                          |
| Wheat                 |               |                              |
|                       | 2,733,205     | 0.4                          |
| Soybean               |               |                              |
|                       | 1,677,028     | 0.2                          |
| Hay                   |               |                              |
|                       | 1,260,536     | 0.2                          |
| Sorghum               |               |                              |
|                       | 346,680,804   | 46                           |
| Cotton                |               |                              |
|                       | 115,534,537   | 15.3                         |
| Barley                |               |                              |
|                       | 80,328,143    | 10.7                         |
| Oats                  |               |                              |
|                       | 30,659,432    | 4.1                          |
| Rice                  |               |                              |
|                       | 25,511,360    | 3.4                          |
| c\) Other^3^ (Non     |               |                              |
| Forest/Ag)            | 21,130,906    | 2.8                          |
|                       |               |                              |
| [Landcover            | 20,681,754    | 2.7                          |
| classes]{.underline}  |               |                              |
|                       | 10,722,279    | 1.4                          |
| Shrubland             |               |                              |
|                       | 10,008,173    | 1.3                          |
| Grassland             |               |                              |
|                       | 8,922,544     | 1.2                          |
| Evergreen needleleaf  |               |                              |
| forest                | 7,162,873     | 1.0                          |
|                       |               |                              |
| Deciduous Forest      | 6,785,266     | 0.9                          |
|                       |               |                              |
| Water                 | 5,208,881     | 0.7                          |
|                       |               |                              |
| Cropland/Grassland    | 1,797,282     | 0.2                          |
|                       |               |                              |
| Savannah              | 1,171,139     | 0.2                          |
|                       |               |                              |
| Dryland Cropland      | 376,533       | 0.1                          |
|                       |               |                              |
| Mixed Forest          | 36,126        | 0.0                          |
|                       |               |                              |
| Shrubland/Grassland   | 14,516        | 0.0                          |
|                       |               |                              |
| Cropland/Woodland     | 13,339        | 0.0                          |
|                       |               |                              |
| Urban                 | 753,646,800   | 100                          |
|                       |               |                              |
| Barren                |               |                              |
|                       |               |                              |
| Irrigated Cropland    |               |                              |
|                       |               |                              |
| Wooded Tundra         |               |                              |
|                       |               |                              |
| Snow/Ice              |               |                              |
|                       |               |                              |
| Evergreen broadleaf   |               |                              |
| forest                |               |                              |
|                       |               |                              |
| Mixed Tundra          |               |                              |
|                       |               |                              |
| Total land area       |               |                              |
+-----------------------+---------------+------------------------------+
|                       |               |                              |
+-----------------------+---------------+------------------------------+

^1^Derived from U.S. Forest Service FIA data

^2^Derived from 1992 Agricultural Census data

^3^Derived from USGS NALCC data

**[Table 4]{.underline}**

  -------------- --------------- ------------- --------------- ------------- --------------- ------------- ----- -----
                                                                                                                 

  Site           BELD2           Forest        BELD3           Forest        OTTER           Forest              
                                 density/                      density/                      density/            

                 forest classes  composition   dominant        composition   dominant        composition         
                                 (%)           species         (%)           species         (%)                 

  1              Forest density  82\*          Forest Density  100           Clown closure   90                  

                                               (range, 4 cell  (13-100)      (range)         (74-100)            
                                               radius)                                                           

                                                                                                                 

                 Conifer forest  99            *Psuedotsuga    39            *Alnus rubra*   50                  
                                               menziesii*                                                        

                 Wood/cropland   1             *Alnus rubra*   29            *Tsuga          17                  
                                                                             heterophylla*                       

                                               *Tsuga          19            *Psuedotsuga    17                  
                                               heterophylla*                 menziesii*                          

                                               *Picea          7             *Picea          17                  
                                               sitchensis*                   sitchensis*                         

                                                                                                                 

  2              Forest density  97                            95                            71                  

                                                               (2-100)                       (31-100)            

                                                                                                                 

                 Conifer forest  91            *Psuedotsuga    49            *Psuedotsuga    80                  
                                               menziesii*                    menziesii*                          

                 Wood/cropland   9             *Alnus rubra*   14            *Acer           10                  
                                                                             macrophyllum*                       

                                               *Acer           11            *Quercus        10                  
                                               macrophyllum*                 garryana*                           

                                               *Quercus        9                                                 
                                               garryana*                                                         

                                                                                                                 

  3              Forest density  88                            91                            100                 

                                                               (38-100)                      (100-100)           

                                                                                                                 

                 Conifer forest  97            *Psuedotsuga    54            *Psuedotsuga    75                  
                                               menziesii*                    menziesii*                          

                 Wood/cropland   3             *Tsuga          19            *Tsuga          25                  
                                               heterophylla*                 heterophylla*                       

                                               *Abies          4                                                 
                                               amabilis*                                                         

                                                                                                                 

  5              Forest density  41                            53                            30                  

                                                               (38-73)                       (19-84)             

                                                                                                                 

                 Conifer forest  57            *Pinus          36            *Pinus          100                 
                                               ponderosa*                    ponderosa*                          

                 Western         38            *Psuedotsuga    23                                                
                 woodland                      menziesii*                                                        

                 Wood/cropland   5             *Juniperous     10                                                
                                               virginiana*                                                       

                                                                                                                 

  6              Forest density  51                            19                            14                  

                                                               (6-23)                        (3-23)              

                                                                                                                 

                 Conifer forest  68            *Pinus          45            *Juniperous     100                 
                                               ponderosa*                    occidentalis*                       

                 Western         29            *Pinus          33                                                
                 woodland                      contorta*                                                         

                 Wood/cropland   3             *Tsuga          8                                                 
                                               heterophylla*                                                     

                                               *Abies          8                                                 
                                               concolor*                                                         

  \* For BELD2,                                                                                                  
  only the                                                                                                       
  forested                                                                                                       
  classes are                                                                                                    
  shown. OTTER                                                                                                   
  field                                                                                                          
  measurements                                                                                                   
  were taken                                                                                                     
  only in                                                                                                        
  forested                                                                                                       
  plots. Values                                                                                                  
  may not sum to                                                                                                 
  100% because                                                                                                   
  of rounding.                                                                                                   
  -------------- --------------- ------------- --------------- ------------- --------------- ------------- ----- -----

**[Table 5]{.underline}**

**[GAP Field Survey BELD3]{.underline}**

**F1**

*Quercus kelloggii Quercus chrysolepis Quercus agrifolia*

*Quercus chrysolepis Pinus jefferyi Quercus kelloggi*

*Quercus agrifola Quercus kelloggi Quercus chrysolepis*

*Pinus lambertiana **Arctostaphylos pungens** Pinus jefferyi*

*Pinus coulteri Pinus coulteri Quercus engelmannii*

***Calocedrus decurrens** **Calocedrus decurrens** Pinus coulteri*

**F2**

*Quercus kelloggi Quercus kelloggii Quercus agrifola*

*Pinus jefferyi Pinus jefferyi Quercus kelloggi*

*Quercus cornelius-mullerii Quercus berberidifolia Quercus chrysolepis*

***Adenostoma fasciculatum** **Ceanothus palmeri** Pinus jefferyi*

*Cercocarpus betuloides Quercus engelmannii*

***Adenostoma fasciculatum** Pinus coulteri*

**W1**

*Quercus agrifola Quercus engelmannii Quercus agrifola*

*Quercus engelmannii Quercus agrifola Quercus kelloggi*

*Quercus kelloggi **Arctostaphylos glandulosa** Quercus chrysolepis*

***Ceanothus lucodermis** **Salvia alpiana** Pinus jefferyi*

***Adenostoma fasciculatum** **Eriogonum fasciculatum** Quercus
engelmannii*

*Quercus berberidifolia Quercus kelloggi Pinus coulteri*

**W2**

*Quercus kelloggi Quercus engelmannii Quercus agrifola*

*Quercus agrifola Quercus kelloggi Quercus kelloggi*

*Quercus engelmannii Quercus berberidifolia Quercus chrysolepis*

***Adenostoma fasciculatum** Quercus agrifola Pinus jefferyi*

***Arctostaphylos tomentosa** Pinus coulteri Quercus engelmannii*

*Cercocarpus betuloides **Arctostaphylos glandulosa** Pinus coulteri*

\* F1 and F2 are forested polygons with closed canopy cover

W1 and W2 are woodland polygons with open canopy cover

Species in **bold** are not inventoried in the FIA database

*BELD2 inventory for San Diego County:*

Western woodland(.46), Western conifer(.41)

Scrub woodland(.12), Woodland/cropland (.1)

**[Table 6]{.underline}**

**Percent Forest Density**

**\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_[\_\_]{.underline}**

**[Polygon GAP\* Field Survey BELD3 \_]{.underline}**

%(+/- SE) %(+/- SE) % (+/- SE)

F1 p = 60-100 72 92

s = 60 -100 (54,90) (85,99)

F2 p = 45-59 54 73

s = 60-100 (44,63) (65,81)

W1 p = 25-39 42 66

s = 60-100 (20,63) (57,75)

W2 p = 60-100 56 63

s = 60-100 (35,76) (49,77)

\* p = primary assemblage

s = secondary assemblage

*BELD2, San Diego County:* Forest fraction = .37

SE = standard error

**[Table 7]{.underline}**

**Isoprene Emissions**

**[Field survey\* GAP\* BELD3\*]{.underline}**

**[Polygon]{.underline}** (μg m^-2^ h^-1^) (μg m^-2^ h^-1^) (μg m^-2^
h^-1^)

Forest (F1) 11,274 13,679 14,631

Forest (F2) 7,580 6,980 3,867

Woodland (W1) 7,914 11,272 13,798

Woodland (W2) 13,873 13,656 10,531

\* Normalized conditions:

Temperature = 30^o^C, PAR = 1000mol m^-1^ s^-1^

Isoprene emission factors taken from *ftp.epa.gov/amd/asmd/beis3v11*