Latest Score:

4.7/5

in 2019

score trend is flat over time
Weight: 13%

While assessments of mature trees provides information about the current condition of Vermont’s forests, densities of sapling give details about the likely softwood composition in the future. Softwood regeneration is a measured as the density of seedlings per acre, inventoried annually on Forest Inventory and Analysis (FIA) plot data. Per FIA protocol, plots are reassessed every 5 years until 2014, and then every 7 years since then. A softwood seedling is classified as a small tree less than 1" in diameter1. Here, a dominant component of the Montane Spruce-Fir Forest, and an ecologically and economically important species, red spruce (Picea rubens), was used as a proxy for all softwood species regeneration. These red spruce regeneration estimates are from Spruce-Fir Forests where we would expect to find red spruce seedlings. The current year is scored for where it falls between zero and the target, scaled to be between 1 and 5.

1USDA Forest Service. 2017. Forest Inventory and Analysis National Core Field Guide, Volume 1: Field Data Collection Procedures for Phase 2 plots. Version 7.2. Available at: https://www.fia.fs.fed.us/library/field-guides-methods-proc/docs/2017/core_ver7-2_10_2017_final.pdf

-- Expert interpretation for Softwood Regeneration is not available--

The score is calculated using a target value and the historical range of the the entire long-term dataset. The higher the score, the closer this year's value is to the target.

Once the score is computed for each year, the trend in scores over time is calculated. If the trend is significantly positive or negative, the long-term trend is marked as increasing or decreasing respectively.

Component Description
Scored as

Distance between 0 and the data maximum (scaled 1-5)

Target value

Data maximum + 10% of the range

Directionality of scores

Higher values in the data are better

Minimum value used in scoring

Zero

Maximum value used in scoring

Data maximum + 10% of the range

We collected counts of red spruce (Picea rubens) seedlings per subplot in the Forest Inventory and Analysis Phase 2 plots via the FIA EVALIDator1. The first year of available data is 2003. A softwood seedling is classified as a small tree less than 1" in diameter and greater than 6" in height2. We averaged seedling counts over all sampled subplots of spruce-fir forests per year and scaled this number to the acreage of a subplot (0.25 ac.) to compute a density value (seedlings per acre). Per FIA protocol, plots are reassessed every 5 years until 2014, and every 7 years after that. To compute the annual score, we used 5-year leading edge moving window (i.e., data reported for 2007 used 2003, 2004, 2005, 2006 and 2007) until 2014 when we switched to a 7-year leading edge moving window per FIA protcol2. The target for this dataset was set to the maximum value plus 10% of the range. The current year is scored for where it falls between zero and the target, scaled to be between 1 and 5

1 USDA Forest Service. 2017. FIA EVALIDator. Version1.8.0.01. Available at: https://apps.fs.usda.govEVALIDator/evalidator.jsp
2 USDA Forest Service. 2017. Forest Inventory and Analysis National Core Field Guide, Volume 1: Field Data Collection Procedures for Phase 2 plots. Version 7.2. Available at: https://www.fia.fs.fed.us/library/field-guides-methods-proc/docs/2017/core_ver7-2_10_2017_final.pdf

STRUCTURE INDICATORS