HomeSoil seriesConroe
Conroe soil series
Conroe soils cover 150,013 mapped acres, almost all of them in Texas. USDA rates shrink-swell a limit for houses without basements on 0% of that land, and a shallow water table a limit for basements on 100%.
It is the leading soil series by area in 7 of the counties and cities on this site, including Montgomery County, TX.
SSURGO survey versions to August 5, 2026 · series description revised 2022-04
of its land: shrink-swell limits houses without basements
of its land: a shallow water table limits basements
median highest linear extensibility (6% and up is high)
median highest clay content in the top 150 cm
USDA's description
The Conroe series consists of deep, moderately well drained, slowly permeable soils that formed in acid clayey and loamy fluviomarine deposits of the Willis Formation. These soils occur on summits of interfluves of inland dissected coastal plains. The slope range is 0 to 12 percent. Mean annual precipitation is about 1245 mm (49 in) and mean annual air temperature is about 19.4 degrees C (63 degrees F).
Source: USDA NRCS series description (OSD) for Conroe, revised 2022-04. Read it.
Engineering properties
| Mapped area (SSURGO) | 150,013 acres |
| Shrink-swell limits houses without basements | 0.0% |
| Shallow water table limits basements | 100.0% |
| Very limited for septic absorption fields | 91.9% |
| Most common drainage class | Moderately well drained |
| Most common hydrologic soil group | B |
| Taxonomic class | Clayey, kaolinitic, thermic Arenic Plinthic Paleudults |
| Type location | Montgomery County, Texas |
Where Conroe is mapped
| State | Mapped acres |
|---|---|
| Texas | 150,013 |
Places where Conroe leads
Counties and cities where Conroe covers more mapped land than any other series.
| Place | Share of mapped land |
|---|---|
| Willis, TX | 64% |
| Panorama Village, TX | 63% |
| Magnolia, TX | 47% |
| Stagecoach, TX | 47% |
| Todd Mission, TX | 40% |
| Conroe, TX | 31% |
| Montgomery County, TX | 15% |
Other places where Conroe is a main soil
Counties and cities where Conroe is among the six soil series covering the most mapped land, but not the first. Share of the place's mapped land.
Counties
Texas and Ohio cities
Sources
Shares and properties: USDA NRCS SSURGO via Soil Data Access, weighted by each component's share of its map units. Description: the USDA NRCS series description. How we count.