Appendix B: Bioengineering for Streambank Erosion Control -- Guidelines
for growing wetland plants in coconut fiber mats (coir mats) was discussed above for the
splash zone and can be extended up into this zone as well.
Instead of using sod in this zone, the California Department of Parks used seed from
wetland plants, such as various sedges and grasses, in combination with burlap and a coir
woven fabric (0.8 lbs/sq yd) laid over the seed (Figure 38). This whole system was placed
in the bank zone above root wads and willow clumps that were installed in the toe and splash
zones, respectively. The combination of root wads, willow clumps, and this seeding and
burlap/coir combination was stable in most reaches where it was installed although vegetative
cover from the planted seed was less than expected. This treatment, along with others, are
described in Volume II.
Figure 38. Burlap and coir woven fabric laid over sedge and
grass seed, Upper Truckee River, California. Note that the
fabrics were keyed in at the top and bottom in trenches and
securely staked with wedge-shaped stakes. (Photo courtesy of
Interfluve, Inc.)
To augment the sodding practice for this milder energy regime, shrub-like willow,
dogwood, and alder transplants or 1 year-old rooted cuttings are effectively used in this zone
(Edminster et al. 1949; Edminster 1949; and Seibert 1968). These transplants or cuttings
should be planted about 0.5 m apart and in rows. Further planting practices can be found in
Edminster et al. (1949) and Edminster (1949). Newly planted banks are usually subject to
additional erosion and the shrub plantings should have mulch placed over them to serve as
temporary protection. Mulch of woody plant branches are best for this and should be the
heaviest on outside curves of the stream where the current strikes the bank. The mulch
B-60
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