Common Forest Inventory was downloaded from http://deli.dnr.state.mn.us/
Data for all Counties in the Northern Superior Uplands was downloaded
(Carlton, Itasca, Koochiching, St. Louis, Lake, Cook)
St. Louis, Lake and Cook were supplied as ArcView polygon coverages
Carlton, Itasca and Koochiching were supplied as ArcInfo export coverages
Converted to ArvView polygon coverages with ESRI's IMPORT71 tool.
The resulting collection of coverages is not yet complete:
State County USFS
Carlton Y N ?
Itasca Y N Y
Koochiching Y Y ?
(? = USFS may not have holdings in these Counties)
All coverages were merged. Note the field Measure_year from the ArcInfo
coverages is called Measure_ye in the ArcView coverages.
Polygons with a zero covertype, age or area were deleted
An Age2000 field was added, being the age of the stand in 2000, by
adding the Age field to the time since the stand was measured (Measure_ye[ar])
The NRV forest type was calculated for each polygon by determining the
majority value of NRV grid cells (30x30 m) within each polygon. ArcView
could not use the existing stand ID numbers because of thier large numerical
range, so an additional id field which simply numbered each polygon from
1 to 103834 was used.
The majority values were taken from the ArcView Summarize Zones output
table (using the added id field and the forest type code in the NRV
grid). These values were then copied back into the Common Inventory data
table by linking the two tables on the id field and adding a field
F2_SU to receive the type value.
The merged data was clipped with polygons representing all the subsections
in the Northern Superior Uplands.
To produce the analysis of current conditions vs. the NRV map a
ArcView Avenue script was written (csa_nrv_comp). For each of the
eight forest types on the Northern Superior Uplands all polygons in
each age range of the type were selected, and the total for each
species (CSA covertype) tabulated.
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