Blog · October 14, 2026 · New Mexico
The Union County Plat Book and the online parcel map
With a lot near Mount Dora, plat books show ownership by township; the parcel viewer shows it today.
Main page: Union County, NM GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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Hunting for the latest Union County plat book? It's a printed atlas of landownership, usually by township, popular with hunters, farmers and buyers near Capulin Volcano National Monument. This Union County guide covers: how the atlas is organized, where to find editions, and how the county viewer fills the gaps.
Getting started with the Union County plat book
If the land is near Folsom, a plat book is a privately published atlas, that map ownership across the countryside, usually township by township.
Pulling up a parcel
If the land is near Capulin Volcano National Monument, the public parcel map for this area is the NM Office of the State Engineer County Parcels 2025 layer in ArcGIS Map Viewer, and no login is needed to use it. Without an address in hand, follow US Route 412 on the aerial and select the outline, and that holds around Capulin Volcano National Monument too. With a lot near Mount Dora, a pop-up or side panel usually lists the owner of record, assessed acreage, a parcel ID and often a sale date.
Taking the map into the field
Most viewers work in a phone browser, which helps when you're standing on land near Grenville, but coverage can be spotty out of town. A screenshot of the parcel near Mount Dora with its ID helps when you meet an owner or agent.
Where the recorded documents are
For a tract near Folsom, the map is an index, not the title: recorded deeds, subdivision plats and easements for parcels in the county sit with the County Clerk. Near Mount Dora, have ready the book and page from the tax record and the lookup takes minutes.
A homemade atlas
Print parcel views near Folsom township by township to build your own up-to-date atlas.
Why people still buy them
Farmers, hunters and appraisers near Des Moines use plat books for a big-picture view of who owns what.
Editions and availability
Libraries near Kiowa National Grassland sometimes keep past atlases, useful for family or title research.
Neighboring parcel maps
Union County meets Baca County, CO, Las Animas County, CO, Colfax County, Harding County, and Quay County, and each of those keeps its own parcel map. Acreage along the edge near Hayden may show up in two county records, so open the adjacent map as well. For a home near Clayton, our state page links every bordering county map across New Mexico.
Union County in a few facts
Clayton is the county seat, which is where the courthouse records live. Other places on the map include Des Moines, Folsom, Grenville, and Capulin, where town lots give way to larger tracts. Roughly 3,964 people live in Union County (Census estimate, 2023) on some 3,825 square miles. Union County was formed in 1894, which matters when you trace an old farm's title. Features like Capulin Volcano National Monument help you orient on the aerial around Mount Dora.
Getting answers from the right desk
Questions about value or the owner field for land near Hayden go to the County Assessor, since that office keeps the assessment data. Questions about what you can build around Mount Dora need the planning or permitting office, depending on whether the land is inside town limits.
Using the parcel viewer instead
Out toward Des Moines, the NM Office of the State Engineer County Parcels 2025 layer in ArcGIS Map Viewer is updated more often than any atlas, across the county.
What the map can't tell you
In and around Des Moines, listed acreage is a tax-roll number; only a licensed surveyor sets the real boundary on the ground. If you're looking near Grenville, owner names and values update on a schedule, so a deed recorded last month may not show yet.
Legal descriptions in New Mexico
New Mexico is laid out under the Public Land Survey System, which means a tract near Capulin is described by section, township and range. Each section is nominally a mile square, about 640 acres, with 36 sections to a township, though real sections near Clayton vary in size. Copy the legal description from the record for the parcel near Grenville before you request a deed or survey.
Atlas or legal document
For a tract near Folsom, don't confuse the atlas with a recorded subdivision plat: the recorded plat at the County Clerk is a legal document, and the atlas is just a guide.
Frequently asked
Is a plat book legal proof near Capulin?
In and around Gladstone, recorded plats are legal documents at the County Clerk, and plat books are references.
Are old plat books online in Union County?
Closer to Grenville, libraries and historical societies hold older editions.
Where can I buy a plat book for land near Capulin?
For a home near Capulin Volcano National Monument, editions come and go; online parcel maps fill the gaps.
Why does the plat book differ from the deed for land near Kiowa National Grassland?
Atlas drawings near Des Moines are simplified; don't rely on them for boundaries.
Is the parcel map a survey for land near Des Moines?
The map near Gladstone is approximate; a survey sets the real corners
Open the official Union County, NM parcel map See it in the Platbookmapper directory
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey, especially for fences, setbacks, or boundary disputes.