Highly weathered volcanic soil

HIGHLY WEATHERED VOLCANIC SOIL

Photo by Tai McClellan

The Hana Series is a characteristic highly weathered, infertile volcanic soil.

• Location: The Hana Series is located on the windward side of East Maui, and it occupies a land area of approximately 8,000 acres. The elevation at which you will find this soil is between sea level and in the uplands of 1,200 ft.
• Texture: Silty clay loam
• Rainfall and Temperature: The average annual rainfall is between 80 and 150 inches, and the average temperature is 73 degrees F.
• Slope: Gently to moderately steep
• Parent Material: The Hana Series was derived from volcanic ash that was deposited over cinders and `a`a lava flows. The depth of the soil profile may extend from 27 to 40 inches.
• Depth: While the surface soil is typically 12 inches, the subsoil extends 22 inches.
• Physical Traits: The surface may be very rocky depending upon the location. The soil has good drainage, with moderately rapid permeability and medium runoff.
• Color of surface horizon: Dark brown/dark grayish brown
• Fertility: The Hana Series is typically deficient in nutrients such as phosphorus.
• Acidity: Strongly to medium acidity
• Natural vegetation: Grasses and tree species.
• Agriculture: Pasture.
• Related Soil Series: Honomanu Series
  

HIGHLY WEATHERED VOLCANIC SOIL VS. MODERATELY WEATHERED VOLCANIC SOIL

The major differences between a highly weathered soil, such as the Honomanu Series (Hana’s sister series) and a moderately weathered soil, such as the Kula Series is highlighted in the following table. The Honomanu Series is acidic and depleted in plant nutrients such as calcium, whereas the Kula Series is slightly acidic and rich in calcium