California Department of Transportation

Hydroseed and Hydromulch

Type D Photo

What is This Treatment?

Hydroseeding is a method of applying seed, fiber, tackifier and other materials to a site via a hydraulic spray rig. Hydromulch work is the same as Hydroseed, only no seed is applied.

The Hydroseed specification includes the following steps:

  1. Seed and fiber are applied to slopes with a hydroseed rig.
  2. Optionally straw is applied with a straw blower.
  3. Fiber and tackifier are applied with a hydroseed rig.

When to Use This Treatment:

  • Use for cut and fill slopes and other disturbed soil areas.
  • Typically used to treat disturbed areas larger than 0.5 acres. Consider using Dry Seeding to hand-seed areas less than 0.5 acres.


  • Immediate protection from surface erosion due to raindrop impact.

  • Helps conserve soil moisture.
  • Low initial cost compared to other treatments.

  • Conforms closely to the soil surface which may result in less erosion due to surface rilling.

  • Vegetation provided by seed provides long-term control of erosion.


  • If local air quality constraints due to straw blowing may be an issue, consider substituting Bonded Fiber Matrix.

  • Higher application rates required for steeper slopes may inhibit germination of seed and establishment of long-term vegetation.

  • Inefficient technique to treat disturbed areas less than 0.5 acres. Consider using Erosion Control (Seeding) instead.

Consider Using With:

To effectively treat sites where Erosion Control (Hydroseeding) may not stay in place, consider combining this treatment with:

To effectively treat sites with poor soils (compacted, nutrient depleted, or poorly draining), consider combining this treatment with:

Plans and Details:

Estimate Information:


External Links:

Updated 04-14-2015