Research, Development, and Application of Methods to Update Freight Analysis Framework Out-of-Scope Commodity Flow Data and Truck Payload Factors
Chapter 8. Logs
Methodological Approach
As shown in figure 56, the process for modeling out-of-scope log commodity flows is based on the portion of the supply chain that constitutes the out-of-scope movement. This solely consists of the movement from the harvest site to the sawmill for processing. Once harvested timber reaches the sawmill, it is an in-scope movement since sawmills are categorized under North American Industry Classification System (NAICS) code 32111.60
The process uses the following data sources:
- United States Department of Agriculture (USDA) Forest Service's Forestry Inventory Data Online (FIDO)—The U.S. Forest Service's FIDO tool provides spatial (at the State and county levels) and temporal (at the annual level) data on timber production.
- USDA Forest Service's Timber Product Output (TPO) Reports—The TPO reports provide the quantity of soft and hard wood from the published "2012 State Level Core Tables."
- State and Region Price Reports—The prices of soft and hard woods provided in various State or Region Price Reports to determine the value of log commodity flows.
- Mill Location Data—Data on the location and size of mills. Potential sources for these data include a USDA geodatabase on mill locations and the U.S. Census Bureau County Business Patterns database. Sawmills are identified by NAICS code 32111.61
Key methodological steps include:
- Estimate County-Level Log Productions—County totals of timber produced are estimated using statistics published in the FIDO and TPO reports. The FIDO contains the amount of tonnage produced at the county level.
- Estimate County-Level Log Attractions—Estimate the State and county totals of timber attracted using the location and size of sawmills. The location and size of sawmills was estimated using data on the number of establishments by county and their total annual payroll for all employees as captured by the County Business Patterns database for establishments under NAICS code 32111. Consumptions zones are also defined at this step in the process which indicate where consumptions take place as shown in table 22. These zones largely follow those used by the USDA Forest Service for purposes of analyzing and reporting data.
- Distribute Log Commodity Flows to Mills—Distribute log commodity flows to mills at the county level using a gravity model (see figure 35). Impedance is a function of network distance between counties as captured by the Oak Ridge National Laboratory County Distance database (see figure 36).
- Aggregate to the Freight Analysis Framework Version 4 (FAF4) Zone Level—After distribution, individually aggregate the county-level productions and attractions to the FAF4 zone level.
The four levels of the framework are estimating county-level productions, estimating county-level attractions, distributing flows between counties, and finally aggregating this to Freight Analysis Framework Version 4 (FAF4) zone levels.
Figure 56. Flow chart. Framework for out-of-scope log shipments.
(Source: Federal Highway Administration.)
Table 22. States by zone for logs.
| Zone |
States |
| Northeast |
- Connecticut.
- Delaware.
- District of Columbia.
- Maine.
- Maryland.
- Massachusetts.
- New Hampshire.
- New Jersey.
- New York.
- Ohio.
- Pennsylvania.
- Rhode Island.
- Vermont.
- West Virginia.
|
| Southeast |
- Alabama.
- Florida.
- Georgia.
- Kentucky.
- North Carolina.
- South Carolina.
- Tennessee.
- Virginia.
|
| South Central |
- Arkansas.
- Louisiana.
- Mississippi.
- Oklahoma.
- Texas.
|
| Great Plains |
- Kansas.
- Nebraska.
- North Dakota.
- South Dakota.
|
| North Central |
- Illinois.
- Indiana.
- Iowa.
- Michigan.
- Missouri.
- Minnesota.
- Wisconsin.
|
| Intermountain |
- Arizona.
- Idaho.
- Nevada.
- New Mexico.
- Utah.
- Montana.
- Wyoming.
|
| California |
|
| Pacific Northwest |
|
(Source: Federal Highway Administration.)
Results
Figure 57 depicts the assumed production-consumption zones for log shipments. These zones were based on the clustering of counties that produce timber across states. Six production-consumption zones are defined for the contiguous U.S.: Northeast, North Central, Southeast, South Central, Great Plains, Intermountain, California, and Pacific Northwest. In keeping with the observation that logging shipments are primarily local, the methodology assumes that out-of-scope (OOS) movements of logs are distributed within these zones.
Also depicted in figure 57 are the results of estimated logging production at the county level. The USDA FIDO database and TPO reports provide much of the information on annual estimates of county-level production by total tonnage directly. However, this data is not collected directly on an annual basis but is instead based on samples taken every five years from which USDA develops annual estimates.
In total, nearly 776,000 tons of logs are estimated to have been produced in 2017 as shown in table 23. Of that total, the Southeast region produced the highest share at 42 percent, followed by the South Central at 21 percent, and the Pacific Northwest at approximately 16 percent. The Northeast, North Central, Intermountain, and California regions are estimated to have produced approximately 20 percent of logs. Figure 39 depicts the methodology's results for the estimation of log attractions at the county level. In general, counties with higher numbers of sawmills and wood preservation establishments (NAICS 32111) as indicated by U.S. Census Bureau County Business Pattern data attract higher amounts of corn farm-based shipments than others.
Table 23. Logs production estimates by region.
| Region |
Tons Produced |
Percent of Total |
| Southeast |
328,208.28 |
42.30% |
| South Central |
165,528.38 |
21.33% |
| Pacific Northwest |
124,362.90 |
16.03% |
| Northeast |
61,738.68 |
7.96% |
| North Central |
35,676.64 |
4.60% |
| Intermountain |
31,154.90 |
4.02% |
| California |
25,402.68 |
3.27% |
| Great Plains |
1,973.66 |
0.25% |
| Alaska |
1,816.67 |
0.23% |
| Hawaii |
– |
0.00% |
| Grand Total |
775,862.80 |
100.00% |
(Source: USDA FIDO, 2012–2017.)
Figure 57. Map. Tons of logs produced at the county level.
(Source: USDA FIDO, 2012–2017.)
Figure 58. Map. Tons of logs attracted at the county level.
(Source: USDA FIDO, 2012-2017; U.S. Census Bureau County Business Patterns, 2016.)
As an example, table 24 shows the results of the analysis of logging shipments for the Remainder of Pennsylvania FAF4 zone. In total, nearly 20,000 tons of logs are estimated to have an origin or destination within this zone not including internal movements. The results indicate that for the Remainder of Pennsylvania zone nearly one-third, over 6,000 tons, log flows are internal. About 6 percent (over 1,200 tons) of flows are outbound while the remainder (about 60 percent or about 12,000 tons) is inbound. That the methodology estimates that over 90 percent of log flows for this zone are either inbound or internal is reflective of its relatively large number of sawmills and wood preservation establishments.
Figure 59 shows the distribution of tonnage by distance for all shipments in the Northeast production-consumption zone. The results indicate that about 34 percent of total tonnage travels 50 miles or less and approximately two-thirds (67 percent) travels 200 miles or less. About 86 percent of total tonnage for the Northeast zone is estimated to travel distances of 500 miles or less. While this is largely consistent with the current FAF4 assumption that log flows are entirely local, the draft methodology does result in about 14 percent of total tonnage traveling distances over 500 miles.
Figure 60 contains the trip length distributions for all harvest site-to-processing shipments of harvested logs in the contiguous U.S. The results indicate that about 31 percent of total tonnage travels 50 miles or less and about 64 percent travels 200 miles or less. About 90 percent of total tonnage for the contiguous U.S. is estimated to travel distances of 500 miles or less.
Table 24. Results for the remainder of Pennsylvania freight analysis framework version 4 zone.
| FAF4 Zone |
Outbound from Remainder of Pennsylvania—Tons |
Outbound from Remainder of Pennsylvania—Percent of Total |
Inbound to Remainder of Pennsylvania—Tons |
Inbound to Remainder of Pennsylvania—Percent of Total |
| New York-Newark, NY-NJ-CT-PA Commodity Flow Survey (CFS) Area (CT Part) |
5 |
<1% |
88 |
1% |
| Hartford-West Hartford-East Hartford, CT CFS Area |
2 |
<1% |
26 |
<1% |
| Remainder of Connecticut |
1 |
<1% |
11 |
<1% |
| Philadelphia-Reading-Camden, PA-NJ-DE-MD CFS Area (DE Part) |
– |
0% |
20 |
<1% |
| Remainder of Delaware |
1 |
<1% |
110 |
1% |
| Washington-Arlington-Alexandria, DC-VA-MD-WV CFS Area (DC Part) |
– |
0% |
– |
0% |
| Remainder of Maine |
5 |
<1% |
4,043 |
34% |
| Remainder of Maryland |
11 |
1% |
679 |
6% |
| Baltimore-Columbia-Towson, MD CFS Area |
9 |
1% |
263 |
2% |
| Washington-Arlington-Alexandria, DC-VA-MD-WV CFS Area (MD Part) |
8 |
1% |
53 |
<1% |
| Boston-Worcester-Providence, MA-RI-NH-CT CFS Area (MA Part) |
4 |
<1% |
78 |
1% |
| Remainder of Massachusetts |
9 |
1% |
31 |
<1% |
| Boston-Worcester-Providence, MA-RI-NH-CT CFS Area (NH Part) |
4 |
<1% |
91 |
1% |
| Remainder of New Hampshire |
9 |
1% |
283 |
2% |
| Philadelphia-Reading-Camden, PA-NJ-DE-MD CFS Area (NJ Part) |
10 |
1% |
14 |
<1% |
| New York-Newark, NY-NJ-CT-PA CFS Area (NJ Part) |
15 |
1% |
69 |
1% |
| Albany-Schenectady, NY CFS Area |
12 |
1% |
314 |
3% |
| Remainder of New York |
218 |
17% |
1,982 |
17% |
| New York-Newark, NY-NJ-CT-PA CFS Area (NY Part) |
27 |
2% |
71 |
1% |
| Buffalo-Cheektowaga, NY CFS Area |
196 |
16% |
215 |
2% |
| Rochester-Batavia-Seneca Falls, NY CFS Area |
25 |
2% |
128 |
1% |
| Remainder of Ohio |
155 |
12% |
667 |
6% |
| Cleveland-Akron-Canton, OH CFS Area |
62 |
5% |
175 |
1% |
| Cincinnati-Wilmington-Maysville, OH-KY-IN CFS Area (OH Part) |
– |
0% |
18 |
<1% |
| Dayton-Springfield-Sidney, OH CFS Area |
5 |
<1% |
19 |
0% |
| Columbus-Marion-Zanesville, OH CFS Area |
8 |
1% |
195 |
2% |
| Pittsburgh-New Castle-Weirton, PA-OH-WV CFS Area (PA Part) |
392 |
31% |
508 |
4% |
| Philadelphia-Reading-Camden, PA-NJ-DE-MD CFS Area (PA Part) |
3 |
<1% |
101 |
1% |
| New York-Newark, NY-NJ-CT-PA CFS Area (PA Part) |
– |
0% |
65 |
1% |
| Boston-Worcester-Providence, MA-RI-NH-CT CFS Area (RI Part) |
– |
0% |
8 |
0% |
| Remainder of Vermont |
– |
0% |
399 |
3% |
| Remainder of West Virginia |
52 |
4% |
1,180 |
10% |
| Total |
1,248 |
100% |
11,905 |
100% |
(Source: Federal Highway Administration.)
This graph is based on data only from the Northeast production-consumption zone. Shipments of 50 miles or less make up the largest share while shipments between 400 and 500 miles make up the smallest share.
Figure 59. Bar chart. Distribution of shipment distances for logs in the Northeast production-consumption zone.
(Source: Federal Highway Administration.)
This graph is based on data from the entire contiguous United States. Shipments of 50 miles or less make up the largest share while shipments over 500 miles make up the smallest share.
Figure 60. Bar chart. Distribution of shipment distances for logs in the contiguous U.S.
(Source: Federal Highway Administration.)
