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GIST 3300 / 5300 Geographic Information Systems Last Lecture State Plane Coordinate System Last Time First Midterm Today Land Division Systems Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Land Division Systems Land Division Systems in the United States - metes and bounds - Louisiana (French) long lots - Spanish (or Mexican) land grants - Public Land Survey System (PLSS) - Original Texas Land Survey Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 1 Midterm 1 Results and Review – GIST 3300 Undergrads 6 90 – 100% 17 80 – 90% 30 70 – 80% 22 60 – 70% 16 50 – 60% 5 < 50% Average 70.9% Range 38.5% to 98.5% Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Midterm 1 Results and Review – GIST 5300 Grads Average 84.2% Range Geographic Information Systems 49.2% to 101.5% 9 5 1 1 1 90 – 100% 80 – 90% 70 – 80% 60 – 70% < 60% Copyright Lucia Barbato 2016 © All Rights Reserved 2 1. Metes and Bounds - “distances and boundaries” - a very unsystematic method of land division Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Metes and Bounds “Follow the wall until you see a barn with a large oak tree on the left.” Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 3 Metes and Bounds - metes and bounds stone marker in a field Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Metes and Bounds - found mostly in the eastern states Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 4 Metes and Bounds Metes and bounds on a topographic map Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Why land division systems matter “Centuries ago, city and county lines were defined by trees and other physical landmarks that have since disappeared”. In 1851 In North Carolina a section of a county boundary was described as “beginning at a gum sapling on the Caswell [county] line and running due South to a birch bush on the bank of the Haw river.” Over time these visible landmarks have vanished, and some cities and counties have become unsure about who should be paying their taxes, attending their schools, and using their services.” If someone is having a heart attack, which county are you going to call? http://www.theatlantic.com/technology/archive/ 2015/10/north-carolina-lost-countylines/409090/ Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 5 2. Louisiana (French) Long Lots - mostly found in areas settled by the French (Louisiana and Quebec) - land was originally subdivided so each property (farm) had river access to receive and transport goods Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Louisiana (French) Long Lots - as land was passed on to sons and subdivided, farms became more and more narrow Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 6 Louisiana (French) Long Lots Long lots seen clearly on a topographic maps in Louisiana Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 3. Spanish (or Mexican) Land Grants - large tracks of land (mostly for ranching) were granted by the Spanish government (and later by the Mexican government) - Seen mainly in TX & CA and parts of the south western US including NM & AZ Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 7 These are the some of the major Texas land grants in the early 1800s. Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Spanish (or Mexican) Land Grants - found mostly in the American southwest - California, Arizona, New Mexico and Texas Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 8 Grant labels and boundaries on a topographic map Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 4. Public Land Survey System (PLSS) - most of the U.S. was subdivided using the Public Land Survey System - also known as Rectangular Survey System or Township and Range Principle Meridian Base Line Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 9 Public Land Survey System (PLSS) Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Public Land Survey System (PLSS) Township N-S designation Range E-W designation - area is referred to as a “township” Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 10 Public Land Survey System (PLSS) - each township consists of a 6 mile by 6 mile grid - with 36 sections Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Public Land Survey System (PLSS) - each “township” covers 36 sq miles (6 x 6 miles) and has 36 sections - each section covers 1 mi2 (640 ac) 6 miles - numbered in a snake-like fashion from north-east corner T2N, R3E Section 22 6 miles Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 11 Public Land Survey System (PLSS) - sections can be further subdivided Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Public Land Survey System (PLSS) Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 12 Public Land Survey System (PLSS) Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Public Land Survey System (PLSS) Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 13 Public Land Survey System (PLSS) Sections on a topographic map Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved Original Texas Land Survey (OTLS) - at the time of the Public Land Survey, Texas was an independent country - in parts of west Texas the OTLS looks very similar to the PLSS - this has produced the square grid of agricultural fields - and the square street grid in the city of Lubbock - in other parts of the state the OTLS looks very different - some parts reflect the irregular shape of the Spanish land grants - other parts resemble the French long lot system Geographic Information Systems Copyright Lucia Barbato 2016 © All Rights Reserved 14 GEOGRAPHIC INFORMATION SYSTEMS Lecture 11: Land Division Systems Land Division Systems - in many applications of GIS, land ownership is an important data layer and it is important for GIS users to be familiar with the most common land division systems used to describe property - a land ownership (cadastral) layer might be a county parcel map, oil leases, or right-of-way easements - it is also important to note that land division systems can have a profound influence on the landscape - land division systems can strongly influence both land use patterns and road networks - these artifacts of various land division systems are often apparent on maps and remote sensing imagery - over the course of U.S. history, five major land division systems have been used Metes and Bounds - a very unsystematic and irregular land division system - property boundaries are defined by referencing fixed points, distances and directions on the landscape - for properties surveyed in the 1700’s and 1800’s, these fixed points were often trees, roads or streams - most widely found on the east coast of the United States Louisiana (French) Long Lots - land originally subdivided to provide farm access to river transportation - as land became subdivided, the original properties became more narrow, resulting in “long lots” - most widely found in areas settled by the French (Louisiana and the province of Quebec) Spanish (Mexican) Land Grants - property boundaries were established by large land grants - these land grants issued first by the Spanish crown and then later by the Mexican government - most widely found in areas settled by the Spanish (southwestern states) Public Land Survey System (PLSS) - also known as the “Rectangular Survey System” or simply “Township and Range” - a land division system originally devised by Thomas Jefferson - established by congress in 1785 for the purpose of subdividing land in new states and territories - land is subdivided based upon the intersection of a Principle Meridian and Baseline - additional survey lines were then laid out from that intersection at 6 mile intervals to form a grid - at regular intervals the grid is modified by correction lines to accommodate the curvature in the Earth - these 6-mile by 6-mile squares are called townships (covering 36 square miles) - the first township south of the baseline and east of the Principle Meridian is called T1S R1W and the other townships are numbered in a similar fashion. - each square mile within a township is called a section (there are 36 section in a township) - these sections are numbered in a snake-like fashion beginning in the north-east corner of the township - the sections can then be further subdivided to identify smaller parcels (e.g. NW ¼, section 22, T2N R3E) - note that Indian Reservations and a few remote mountainous areas are not subdivided using the PLSS Copyright© 2015, Kevin Mulligan, Texas Tech University Public Land Survey System – based on principle meridian and base line in different areas Once the Principal Meridian and base line were established, they surveyed the T & Ranges. T is a N-S designation and Range is an E-W designation. And the area is simply referred to as a township. In this particular example the area in red is referred to as T 2 N R 3 E. Because it is a rectangular survey system applied to the curved surface of the earth, every now and then there are correction lines. And these are really cool because you could be driving along a straight road N or S in Kansas and all of sudden there is a major jog in the road for no apparent reason. Each 6x6 mile township is further divided into 36 sections which are numbered in a snakelike fashion starting in the NE corner. So now you can identify a 640 acre or 1 square mile piece of land. 640 acres is considered a fundamental land unit called a section. You’ll often hear farmer talk about their section of land. Copyright© 2015, Kevin Mulligan, Texas Tech University Example Land description based on the PLSS Original Texas Land Survey (OTLS) - Texas is not part of the Public Land Survey System - at the time the PLSS was surveyed in the United States, Texas was an independent country - in parts of west Texas (e.g. Lubbock county), the OTLS looks very similar to the PLSS - this has produced the square grid of agricultural fields and the square street grid in city of Lubbock - in other parts of the state, the OTLS is very different - some parts reflect the Spanish land grants – and some parts are similar to French long lots Copyright© 2015, Kevin Mulligan, Texas Tech University