Baltimore County's Urban Rural Demarcation Line (URDL) has divided the county into "urban" and "rural" areas since established by the Planning Board in 1967. Developed primarily as a growth management tool, it has influenced zoning, land-use, and infrustructure decisions, and was the baseline for the Baltimore County part of Maryland's Priority Funding Area. However, this boundary (digitized at a scale of 1:24,000 where 1" represents 2,000') was became obsolete as the county's GIS data increased in resolution (to 1:2,400 where 1" represents 200'). Until recently, determining a property's status as either urban or rural was of a highly interpretative nature. A new URDL was developed to more accurately match the 1:2,400 data (parcel, street centerline, zoning, etc). This version was reviewed and modified in a series of meetings with several interested county agencies. The new URDL removes much of the old one's ambiguity while keeping its original intent. The new URDL was reviewed, modified, and subsequently approved by the Planning Board on June 19, 2003. Minor revisions were effected 9/2/04, 10/21/04, 9/4/07, 5/21/09, 10/1/09 and 11/15/12. The URDL_poly feature class is one part of the URDL feature dataset.

Existing boundaries of State-approved Rural Legacy areas. Baltimore County contains all or portions of 5 Rural Legacy areas: Piney Run, Coastal, Manor, Gunpowder and Long Green. This data includes the current and historical boundaries of each area.

State of Maryland Priority Funding Area boundary dataset. This dataset is created and maintained by the Maryland Department of Planning. These boundaries are not intended to serve as a legal description. Fields:CPFA (Certified PFA): If field is populated as “IN” then the PFA has been designated at a Priority Funding Area locally. MUN_CODE (Municipality Code): MUN = within Priority Funding Area (PFA); MUNCOM = PFA with comment; MUN_NONPFA = not in PFA Rural Village Code (RUVI_CODE): RV = within a Rural Village Rural Village Name (RUVI_NAME): Name of the Rural Village COMMENT_STATUS (Comment Status): If field is populated with “NO” then there is no state-placed comment on the area. If the field is populated with “YES” then the state has placed a comment on the area based on eligibility. ACRES (GIS Acres): GIS calculated acres. JURSCODE (Jurisdiction Code) – Four letter county code: ALLE (Allegany), ANNE (Anne Arundel), BACI (Baltimore City), BACO (Baltimore County), CALV (Calvert), CARO (Caroline), CARR (Carroll), CECI (Cecil), CHAR (Charles), DORC (Dorchester), FRED (Frederick), GARR (Garrett), HARF (Harford), HOWA (Howard), KENT (Kent), MONT (Montgomery), PRIN (Prince George’s) QUEE (Queen Anne’s), SOME (Somerset), STMA (St. Mary’s), TALB (Talbot), WASH (Washington), WICO (Wicomico), WORC (Worcester).CERT_DATE (Certification Date) (DD/MM/YYYY): This date is known as the “Certification Date” of the PFA. The date 1/1/1997, or NULL, is used as a default date of when the PFA was certified were first indicated in the GIS layer and not necessarily of when it was actually certified. If there's a date of 1/1/1997, it can be assumed that the PFA was certified on, or before this date. STATE_ELIGIBLE_STATUS (State Eligible): This field is based on whether the PFA has a comment. If there is no comment, then the field will be populated with YES; if there is a state-placed comment, the field will be populated with NO. Point of Contact: Ellen Mussman ellen.mussman@maryland.gov and Meagan Fairfield-Peak meagan.fairfieldpeak@maryland.govDate Last Updated 10/22/2024This is a MD iMAP hosted service. Find more information on https://imap.maryland.gov.https://mdgeodata.md.gov/imap/rest/services/PlanningCadastre/MD_PriorityFundingAreas/FeatureServer/0

Census designated places (CDPs) are closely settled, named, unincorporated communities that generally contain a mixture of residential, commercial, and retail areas similar to those found in incorporated places of similar sizes. The Census Bureau works with local participants to delineate boundaries for CDPs. By defining CDPs, the Census Bureau can tabulate and disseminate data for localities that otherwise would not be identified as places in the decennial census data products. Each CDP will contain an identifiable core encompassing the area that is associated strongly with the CDP name and contains the majority of the CDP's population, housing, commercial structures, and economic activity. A CDP must comprise a reasonably compact and continuous land area internally accessible to all points by road. (Except where parts of a CDP are separated by a narrow corridor of incorporated territory, or where the topography or geographic patterns of settlement are not compact, but are irregularly shaped.) A CDP may not be located partially or entirely within an incorporated place or another CDP. A CDP encompasses the surrounding closely settled territory associated with the place name. The Census Bureau does not intend for a CDP to be an apartment complex or residential subdivision in densely settled areas or simply a crossroads in rural areas.
There are no minimum or maximum population thresholds for recognition as a CDP. This represents a substantial change from all prior CDP criteria.

Relative frequency of terrestrial isopod species in urban and rural forests Introduction The Baltimore Ecosystem Study (BES) has established a network of long-term permanent forest plots. These plots will provide long-term data on vegetation, soil and hydrologic processes in the key ecosystem types within the urban ecosystem. The current network of study plots includes eight forest plots, chosen to represent the range of forest conditions in the area. The goal of the soil invertebrate survey was to compare community composition and abundance of soil macrofauna, primarily earthworms (Oligochatea), terrestrial isopods (Isopoda: Oniscidea), and millipedes (Diplopoda). Plot Locations and Characterizations In November of 1998 four rural, forested plots were established at Oregon Ridge Park in Baltimore County northeast of the Gwynns Falls Watershed. Oregon Ridge Park contains Pond Branch, the forested reference watershed for BES. Two of these four plots are located on the top of a slope; the other two are located midway up the slope. Four urban, forested plots were established in November 1998, two at Leakin Park and two adjacent to Hillsdale Park in west Baltimore City in the Gwynns Falls. One of the plots in Hillsdale Park was abandoned in 2004 due to continued vandalism. Plot locations: Hillsdale 1: 39�19'28.14"N, 76�42'16.49"W Hillsdale 2: 39�19'31.24"N, 76�42'28.62"W Leakin 1: 39�18'1.32"N, 76�41'37.08"W Leakin 2: 39�18'5.42"N, 76�41'34.15"W Oregon top-slope - 1: 39�28'51.11"N, 76�41'22.50"W Oregon mid-slope - 1: 39�28'51.32"N, 76�41'18.24"W Oregon top-slope - 2: 39�29'12.74"N, 76�41'22.88"W Oregon mid-slope - 2: 39�29'12.68"N, 76�41'18.62"W Soil arthropods were sampled between November 1999 and 2000 using pitfall traps. At each plot a total of ten traps were placed which were emptied monthly. Earthworms were sampled using a combination of formalin solution (Raw 1954) and mustard suspension. 50cm x 50cm quadrats were used. Earthworms samples were taken is spring, summer and fall 1999, 2000, and 2002. In addition several qualitative samples were taken from residential and commercial areas in the city. Data were collected between Sep 1999 and April 2000. Ten pitfall traps were placed around each permanent forest plot and emptied monthly. Animals were later identified in the lab. N indicates total number caught during this period.

Although amphibians use human-created habitats in urban landscapes, few studies have investigated the quality of these habitats. To assess habitat quality of stormwater management ponds and adjacent urban uplands forwood frogs (Lithobates sylvaticus) and American toads (Anaxyrus americanus), we compared life history characteristics between populations breeding across an urbanization gradient. Specifically, we compared body size, ages of breeding adults, and female reproductive investment among urban, suburban, and rural populations in Baltimore County, Maryland, USA. Although there was variation in age at maturity among populations, ages of breeding adults did not differ among urban, suburban, and rural areas. Maternal body size strongly influenced reproductive investment in both species, but relationships did not vary among urban, suburban, and rural populations. Adult wood frogs and American toads from more urbanized landscapes were significantly smaller at age than conspecifics from rural landscapes; the magnitude of differences was similar across adult age classes. Our results suggest that in the urban and rural landscapes that we studied, adult habitats are similar in quality, but either larval or juvenile habitats may be of lower quality in urban areas.