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Importing Maps

Updated: Oct 28, 2023

This Study Group discusses importing inventory maps into the City of Montesano inventory.


Topics are:

1. Exporting form Arc GIS

2. Importing Into Assisi

3. Copying Polygons Across Yearly Inventories

4. Filling in Missing Data


Step 1. Exporting From ArcGIS

The first step is to create a KML layer of stand boundaries. The only requirement Assisi has is the the KML layer have one attribute that will be used to match to existing Assisi stands and an attribute that will form new stand names. A single attribute can be used for both matching and name.

We couldn't figure out how to export attributes to KML using ArcGIS other than the polygon name value. So we exported number as Name and created the KML file from that. This meant we would have to match Name with Assisi's Number field and also use Number as the new stand names. Montesano uses the traditional Township, Range, Section & Number for stand names. e.g. "17N07W059200". So we will have to rename new stands after import. Not a big deal for a small number of stands.

The traditional TRSN formats TRS values in 2 digits and Number in 4. Meaning, a Number of 23 is formatted as "0023". ArcGIS exports Number with no leading 0's however, so after loading the KML file, we had to reformat Number into 4 digits using SQL.


Step 2. Importing Into Assisi


Step 3. Copying Polygons Across Yearly Inventories

With the 2023 stands layer in, we can now copy it across the other yearly inventories. We have inventories from 2015 through 2023. All we need to do is match on stand name and update these Stands table fields:

Geometry - Holds polygon info in text format.

Latitude/Longitude - Lat/Lon of geo center of stand.

GISArea - Area of polygon.


A SQL such as this should work:

UPDATE Stands AS Source 
INNER JOIN Stands ON Source.Stand = Stands.Stand 
SET 
Stands.Geometry = [Source].[Geometry], 
Stands.Latitude = [Source].[Latitude], 
Stands.Longitude = [Source].[Longitude], 
Stands.GISArea = [Source].[GISArea]
WHERE Source.Unit="Monty 2023"

Step 4. Filling in Missing Data

At this point we have polygons for all yearly inventories that have the same stands as are in 2023. But what about older stands that have been removed? Polygons for these will have to come from another source or hand drawn in the Field Data Editor.


Notes

Area - Assisi has fields for many types of areas: gross, net, legal, etc.. But it's the Stands.Area field that is used as the reporting and calculation field. GISArea must be copied to the Area field for it to be used to update inventory values.



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