Harper County Soil Data
Harper County, Oklahoma
Avg pH
7.1
Texture
Water
Drainage
N/A
Organic Matter
1.3%
Hydrologic Group
D
Data Story
About Soil in Harper County, Oklahoma
Sweet Soils of the High Plains
Harper County features an average pH of 7.15, making it the most alkaline soil in this group and significantly higher than the national 6.5 median. This 'sweet' soil is common in drier climates where minerals aren't leached away by heavy rain. The overall soil score of 31.9 is slightly below the state average of 35.3.
Sand-Heavy Plains Composition
The soil is comprised of 46.7% sand, 31.4% silt, and 16.9% clay. This high sand ratio provides an open structure that prevents heavy compaction, though the low clay content means fewer sites for nutrient binding. The dominant texture is influenced heavily by the presence of water features and riparian corridors.
Average Water Capacity in Harper
Harper County achieves an available water capacity of 0.146 in/in, slightly exceeding the Oklahoma state average. However, organic matter remains low at 1.28% compared to the 2.0% national benchmark. This means the soil is surprisingly good at holding moisture, even if it is lean on nutrients.
Group D Infiltration Challenges
The county's soil is categorized in Hydrologic Group D, which typically exhibits slow infiltration and high runoff rates. This suggests that during heavy downpours, the soil surface can quickly become saturated. Proper land grading is essential to manage water flow and prevent localized flooding.
Growing in the 7a Hardiness Zone
In Zone 7a, Harper County is well-suited for alfalfa and other deep-rooted forage crops that can tap into stored moisture. Gardeners should look for plants that tolerate alkaline conditions, such as asparagus or certain varieties of beans. Adding organic matter is the best way to improve the 31.9 soil score for home gardening.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group D — High Runoff
Clay soils with very slow infiltration rates. Highest runoff potential. These soils have a permanent high water table or are shallow over impervious material.
Drainage Class
Drainage class data not available.
Soil Profile
Dominant texture: Water
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does Harper County have?
Harper County's soil is classified as Water. This indicates the relative proportions of sand, silt, and clay — 47% sand, 31% silt, and 17% clay. Sandy soils drain quickly but may need more frequent irrigation and fertilization.
Is Harper County's soil acidic or alkaline?
Harper County's soil has a pH of 7.1, which is near neutral. This range is ideal for most garden plants and field crops.
What is the drainage class for Harper County?
Drainage class data is not currently available for Harper County.
What crops or plants grow well in Harper County's soil?
Based on Harper County's Water texture, pH of 7.1, and drainage class, the soil is well suited for drought-tolerant crops and native grasses.
What USDA soil order is found in Harper County?
The dominant USDA soil order for Harper County is not currently available in our dataset.
Planning your lawn? View lawn care data for Harper County on LawnByCounty.com →
Other Counties in Oklahoma
Soil data sourced from USDA SSURGO via Soil Data Access. Data is informational only and should not be used as a substitute for on-site soil testing. Contact your local NRCS office for site-specific soil information.