We tackled the fill slope portion of the trail yesterday. Kind of complex because we had to wrap and reinforce. Innovative stuff but only alternative given the constraints and "sapping/subsurface" conditions. All in all, a pretty good day for 6 people.
Here are some pics!
Here are some photo taken at the Hwy 44 - Palisades Trail after a year. The intent of the planting design was to try a form of "Dormant Planting". No irrigation was recommended.
As you may remember, this slope was seeded with CA native grasses in March of 2015. The hope and scientific quess was that Stipa pulchra ( Nassella - purple needle grass) would establish and really "carry the weight" of long-term soil stabilization - deep fibrous roots, well adapted to climate and site conditions, longevity (did you know this perennial can live 80-years!).
However, these natives can take 2 or more years to become established and the erosion control professional must determine how the site can be protected until the native grass can become established. At this site extra special methods were used to prevent erosion, sapping and soil failure. These methods were applied like a layer cake, 1. soil preparations, smooth uniform grading, 2. seed and mychorrizae were added, 3. a 1" thick layer of compost mixed with tackifier was hand applied, 4. ENKA turf reinforcement mat was carefull applied and anchored to the soil surface with an assortment of anchor pins, 5. lastly was the application of Green Armor System which consisted of Profile Flexterra hydromulch applied ("shot into") directly into the and through the 3-dimensional ENKA Mat. Note that the other half of the prescribed seed was applied with the hydromulch.
This project was similar to the Coastal Bluff Stabilization done in Coastal Erosion Fix - Two Years Later