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Straw

Straw is frequently used as a mulch in hydroseeding, often in conjunction with drill seeding. Application rates vary based upon straw material, slope roughness, and slope steepness. Select one of the products from the detailed information provided below.

When to Use this Product

Specify a straw type when filling out the Hydroseed and Straw specifications.

Weed Free Straw

Certified weed-free forage is defined as: hay, feed, straw or straw mulch that has been inspected, and certified not to contain propagative plant parts or seeds of noxious weeds. County Agricultural Commissioners, in conjunction with the California Department of Food and Agriculture (CDFA), offer inspection services to certify materials as weed free. A survey of producers and suppliers has been completed and the availability list is ready for use. To view the availability list, go to one of these California Department of Food and Agriculture – Pest Exclusion web pages:

Note:

1. If you need a large amount of material for the coming year, contact vendors early in the growing season to make sure sufficient weed-free forage/straw will be certified and available for your project needs.

2. Proof of certification, in the form of a copy of CDFA Form 66-079 “Certificate of Quarantine Compliance (CQC)” associated with the inspection of the specific forage/straw materials, is the legal documentation verifying that the materials have been inspected.

3. Producers seeking certification for weed-free hay and straw: contact your local County Agricultural Commissioner’s office to arrange inspection and certification. Contact information is available at: http://www.cdfa.ca.gov/exec/county/countymap/

Straw Types

Click here to view a chart comparing the benefits and limitations of various straw materials.

If you are uncertain which straw product to select, specify wheat straw. Specify rice straw or Certified Weed Free wheat straw where the potential spread of noxious plant species is a concern.

Wheat Straw

Benefits:

  • Most commonly available straw product.
  • Commonly available in Southern California - unlike Rice Straw.

Limitations:

  • Biodegrades more quickly than rice straw.
  • Wheat straw may contribute to the spread of invasive weeds. Specifying certified weed free straw would help mitigate this problem. Information on sources for Certified Weed Free Straw are available at the following web sites:
  • If you need a large amount of material for the coming year, contact vendors early in the growing season to make sure sufficient weed-free forage/straw will be certified and available for your project needs.
  • CDFA Form 66-079 "Certificate of Quarantine Compliance (CQC)" is the document that verifies that the materials have been inspected.

Rice Straw

Benefits

  • Use where "weed free" straw straw is required. Because rice is aquatic, it has minimal weed seed content when used in dryland applications.
  • High silicate content tends to cause rice straw to last longer than other straw types.
  • Using this straw helps satisfy "Rice Straw Burning Reduction Act" of 1991 (AB-1378) requirements.

Limitations:

  • Availability may be limited seasonally. Verify availability at the Rice Straw Market.
  • As most rice is grown in the Sacramento valley, availability may be limited to northern California. Verify availability at the the Rice Straw Market.
  • Rice straw is brittle and does not "punch" well into the soil. Do not specify rice straw with Erosion Control (Punched Straw).

Barley Straw

Benefits

  • Softer and more absorbent than wheat or rice straw straw.

Limitations:

  • Availability may be limited compared with Wheat straw.

External Links

Straw Talk