|
Green
highlighted words indicate definitions and links
to the glossary section.
CIWMB/Caltrans Workshops
The California Integrated Waste Management Board, in partnership with the
Caltrans Headquarters Landscape Architecture Program, has been holding
workshops throughout the state focusing on new special provisions using
compost to improve
roadside vegetation and reduce erosion.
Other Past CIWMB Erosion Control Projects
The CIWMB has funded several projects involving applications of mulch
to various Napa
and Sonoma County hillside vineyards as erosion control. Using mulch in other grower
settings such as lemon orchards in Ventura County has shown promising results to date in
both erosion control and weed suppression. In addition, the Board is nearing completion on
a project with the Department of Transportation (Caltrans) that uses various mulch,
compost, and
co-compost materials as erosion
control materials for re-vegetation of roadsides that could potentially erode.
Vineyard
Erosion Control
In March 1999, the Board awarded contracts to two partnerships in the Napa/Sonoma area to
demonstrate the effectiveness of mulch on hillside erosion control in
vineyards. Both groups spread mulch made from yard trimmings on hillside vineyards in
the winter of 2000 and will monitor erosion after each major storm event until May 2001.
Orchard Erosion Control
Erosion control professionals have evaluated municipal mulch and various types of compost
under field situations as surface amendment material for erosion control and
re-vegetation
of disturbed or degraded soils. A municipal mulch demonstration
conducted by University of California (U.C.) Cooperative Extension, Ventura County
indicates soil erosion, soil compaction and snail activity are significantly reduced with
the use of yard trimmings in commercial citrus orchards. The mulch applied at least 3
inches deep in the orchard rows also provides weed suppression, soil moisture
conservation, water infiltration, soil fertility, improved soil structure, and moderation
of soil temperatures.
Roadside Erosion Control
A Caltrans/U.C. Davis literature review and research study
found that various types of compost made from municipal yard trimmings and other organic
materials are excellent amendment materials for roadside erosion control. The study
documented that composts vary considerably in physical and chemical characteristics. More
research is needed to explore the great potential that exists in establishing plant growth
on harsh erosion sites with compost containing slow-release forms of nutrients. Plant
available moisture and nitrogen are often the major limiting factors to plant
establishment on disturbed soils. The mulch effects and organic substrates contained in
compost are expected to regenerate some of the functions of natural soil organic matter
including decreased evaporation from the soil surface, increased microbial activity for
soil aggregate formation, improved slow-release nutrient availability, and improved
nutrient and water holding capacity.
Erosion Control Publications
The following publications are available from the Board's online publications catalog,
or by calling 1-800-CA-WASTE (toll free in California).
External Links
Organics Home |
