Forest Layer (2008 imagery derived)

ESRI ArcCatalog 9.3.1.3000 Forest coverage of Montgomery County, MD. Digitized manually from 2008 aerial photography. Identify those areas of Montgomery County that are forested. en M-NCPPC 2009 Forest Layer (2008 imagery derived) vector digital data withheld Maryland-National Capital Park & Planning Commission (Montgomery County) Silver Spring, MD Forest_2013 Publication date 20080430 Complete None Planned -77.528245 -76.888345 39.347608 38.934794 ISO 19115 Topic Category environment EPA GIS Keyword Thesaurus Land None Maryland Montgomery County, MD United States None. None. Please check sources, scale, accuracy, currentness and other available information. Please confirm that you are using the most recent copy of both data and metadata. Acknowledgement of the EPA would be appreciated. FIPS Pub 199 No Confidentiality Standard Technical Controls M-NCPPC Feature Class ESRI ArcCatalog 9.3.1.3000 Forest_2025 1162940.631895 1343910.130314 612189.969949 462265.198136 1 0.000000 0.000000 -77.528245 -76.888345 39.347608 38.934794 1 1 -77.528160 -76.888343 39.348474 38.934405 0.000000 0.000000 Forest locations in Montgomery County, MD based on 2023 aerial photography. <DIV STYLE="text-align:Left;"><DIV><DIV>The 2008 forest layer was modified using 2015 air photos, generally at the 3000’ scale. Using WSSC’s grid, various editors modified the layer on a grid-by-grid basis. Each grid also received a second review to ensure unified standards. The forest edge generally follows the edge of the forest floor. Forest quality was not determined, so this layer includes existing forest areas with a forest floor that are a minimum 50-feet wide with at least 10,000 sqft, and forests that were either planted or began to regenerate in or before 2008.The 2023 forest layer was modified by comparing the 2015 air photos to the 2023 air photos. Edits first began by observing developments constructed since 2015 to identify areas of forest loss. Then, edits were performed at the countywide level by using WSSC grids, generally at the 3000' scale. Areas for forest deletion were identified and then approved by multiple members of the M-NCPPC team. Once the areas were approved or modified, the geoprocessing "Erase" tool was performed to cut out old forest areas. a. Areas that were generally excluded from the forest layer include:- Structures with driveways and surrounding maintenance/uses.- Lawns and other uses that exclude the forest floor.- New corridors of disturbance such as for utility maintenance.- Ponds and large bodies of water.- Unmaintained areas with no visible trees growing within the vegetation.b. Areas that could be included within the forest:- Trails- Unpaved roads on private property with no shoulder maintenance.- Small structures with an intact surrounding forest floor. - Natural forest gaps if no more that 30-50-feet wide and surrounded by a 300-foot margin of forest.The 2023 forest layer were then further modified using 2023 aerials. The edits are stored in the STATUS field: Add, Delete and No Change refer to the difference between the first 2023 update (see above) and the latest edits. <OL STYLE="margin:0 0 0 0;padding:0 0 0 0;"><LI>For more information, contact: Reagan Ogburn (reagan.ogburn@montgomeryplanning.org) Forest Conservation Planner with Reforest Montgomery, T: 301-495-4576 or GIS Manager Information Technology & Innovation (ITI) Montgomery County Planning Department, MNCPPC T: 301-650-5620</LI></OL>Detailed Methodology:1. Review at 6000’ scale using latest aerials2. Check existing forest for new structures or other openings.3. Check existing forest interior openings. Those that are less than 30-50’ wide with no structure or obvious maintenance/disturbance can be closed. Roads with maintained shoulders should not be closed. Obviously new roads should not remain closed.4. Openings around riparian areas do not break the forest canopy if they are surrounded by forest that equals at least a 300-foot width. 5. Repair forest edges that are excessively wavy with too many vertices. When working with a forest polygon like this, either splice off the wavy edge or create a new polygon edge that encloses that edge. Too many vertices make the layer difficult to manipulate.6. Check if there appears to be new forested areas outside the previous forest layer.7. Use air photos from previous years to assess the number of years a forest has been present or developing. A forest must have been developing for at least 7 years in order to be included in the forest layer.8. Check Forest Conservation Easements layer start date to help assess the start of a new forest.9. When extending a significant amount of new forest to an existing forest, create a new polygon that overlaps the existing forest polygon. Select both, then merge. Choose the attributes of the original polygon. 10. Ponds or large bodies of water do create a forest edge.11. Pay particular attention to large forest areas with interior forest. </DIV></DIV></DIV> Information Technology & Innovation (ITI), Montgomery County Planning Department, MNCPPC Environment Forests Montgomery County Planning Department Montgomery County MNCPPC Maryland <DIV STYLE="text-align:Left;"><DIV><DIV>You can copy, modify, distribute, and perform analysis on the data, even for commercial purposes, all without asking permission, but please provide attribution to the Montgomery County Planning Department. The Planning Department makes no warranties about the data, and disclaims liability for all uses of the data, to the fullest extent permitted by applicable law.</DIV></DIV></DIV> FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time 20090729 20130729 M-NCPPC REQUIRED: The person responsible for the metadata information. REQUIRED: The mailing and/or physical address for the organization or individual. REQUIRED: The city of the address. REQUIRED: The state or province of the address. REQUIRED: The ZIP or other postal code of the address. REQUIRED: The telephone number by which individuals can speak to the organization or individual. en ISO 19115 Geographic Information - Metadata DIS_ESRI1.0 dataset Downloadable Data 24.708 Although these data have been processed successfully on a computer system at the M-NCPPC, no warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data to evaluate data set limitations, restrictions or intended use. The M-NCPPC shall not be held liable for improper or incorrect use of the data described and/or contained herein. M-NCPPC 002 withheld 24.708 Feature Class Feature Class Vector Simple FALSE 0 TRUE FALSE 0 GISADMIN.forest_2008 Presence of forest Feature Class 0 Shape Feature geometry. ESRI Coordinates defining the features. OBJECTID OID 4 10 0 STATUS SOURCE_YEAR String 255 0 0 OBJECTID Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. UPDATE_YEAR String 255 0 0 UPDATE_YEAR ACRES Double 8 38 8 ACRES Area of forest unit in acres SHAPE Geometry 4 0 0 Esri Positive real numbers that are automatically generated. SHAPE Feature geometry. ESRI Coordinates defining the features. STATUS String 255 0 0 SHAPE.AREA SHAPE.AREA Double 0 0 0 SHAPE.LEN SHAPE.LEN Double 0 0 0 20251021 coordinate pair survey feet 0.000536 0.000536 North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 GCS_North_American_1983 NAD_1983_StatePlane_Maryland_FIPS_1900_Feet Explicit elevation coordinate included with horizontal coordinates 1.000000 NAD_1983_StatePlane_Maryland_FIPS_1900_Feet EPSG 5.3(9.0.0) Tests for integrity have not been performed. Features represented have not been tested for completeness Dataset copied. Dataset copied. 20251021 17074900 20251021 17074900 Forest_2023b 002 1162966.433270 1343910.130437 462123.541556 612505.506540 1 Projected GCS_North_American_1983 Linear Unit: Foot_US (0.304801) NAD_1983_StatePlane_Maryland_FIPS_1900_Feet <ProjectedCoordinateSystem xsi:type='typens:ProjectedCoordinateSystem' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns:typens='http://www.esri.com/schemas/ArcGIS/10.6'><WKT>PROJCS["NAD_1983_StatePlane_Maryland_FIPS_1900_Feet",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",1312333.333333333],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-77.0],PARAMETER["Standard_Parallel_1",38.3],PARAMETER["Standard_Parallel_2",39.45],PARAMETER["Latitude_Of_Origin",37.66666666666666],UNIT["Foot_US",0.3048006096012192],AUTHORITY["EPSG",2248]]</WKT><XOrigin>-120561099.999716</XOrigin><YOrigin>-95444399.998166203</YOrigin><XYScale>1867.3770826087002</XYScale><ZOrigin>0</ZOrigin><ZScale>1</ZScale><MOrigin>0</MOrigin><MScale>1</MScale><XYTolerance>0.0042840838492159998</XYTolerance><ZTolerance>2</ZTolerance><MTolerance>2</MTolerance><HighPrecision>true</HighPrecision><WKID>102685</WKID><LatestWKID>2248</LatestWKID></ProjectedCoordinateSystem> 20230724 12424800 1.0 FALSE 150000000 5000 ItemDescription