ECM of Urban Land - Mulching | Erosion Control Measures

Mulching:

Similar to seeding, mulching is a method of applying plant or non-plant materials to cover bare soil surface. The main goal of mulching is to protect the surface of the soil from the impact of erosive forces. In construction sites, mulch can be placed to minimize wind and water erosion. However, the type of mulching selection depends on the land (i.e., slope). Heavy and large sized mulch would be more appropriate for a steep slope. In steep or gentle slopes, matting can be done to hold the mulch in place and reduce its movement by wind or water. Aside from protecting the soil from erosion, mulching conserves water and reduces soil temperature fluctuations. If the mulch is plant-based or organic, it also increases the soil tilth. For a table of the advantages and disadvantages of various mulch types, click the button below.

Mulch Materials
Material	Type	Advantages	Disadvantages
Bark Mulch	Organic (plant based)	slowly builds organic matter relatively inexpensive	periodic application needed easily blown away under windy conditions may not be appealing aesthetically
Wood chips	Organic (plant based)	slowly builds organic matter relatively inexpensive	periodic application needed easily blown away under windy conditions may not be appealing aesthetically
Leaves	Organic (plant based)	builds organic matter relatively inexpensive decomposes relatively fast adds nutrients to the soil	periodic application needed Mixing may be necessary to avoid leaves being blown may not be appealing aesthetically
Grass Clippings	Organic (plant based)	builds organic matter relatively inexpensive decomposes relatively fast adds nutrients to the soil	periodic application needed Mixing may be necessary to avoid leaves being blown may not be appealing aesthetically
Newspaper	Organic (plant based)	slowly builds organic matter relatively inexpensive	periodic application needed Mixing may be necessary to avoid leaves being blown may not be appealing aesthetically
Compost	Organic (plant based)	builds organic matter relatively inexpensive decomposes relatively fast adds nutrients to the soil	periodic application needed may not be appealing aesthetically
Crushed stone, gravel, volcanic rock	Inorganic (non-plant)	periodic application not necessary appealing aesthetically	does not build organic matter relatively expensive
Plastics	Inorganic (non-plant)	periodic application not necessary appealing aesthetically relatively inexpensive	does not build organic matter may not be appealing aesthetically can increase soil surface temperature to the extreme
Geotextiles	Inorganic (non-plant)	especially useful in high velocity flows, such as creek and stream bank protection periodic application not necessary appealing aesthetically	does not build organic matter may not be appealing aesthetically may need to be replaced periodically because of wear and tear relatively expensive

Fact Sheets:

http://msue.anr.msu.edu/news/mulch_just_do_it

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs143_023231.pdf

Thinking Question:

Compare plant-based mulch and the synthetic mulch. Discuss the advantages and limitations of both. Why might a contractor choose one over the other?