[adamlau]

Hello all! Residential home contractor from the San Gabriel Valley region of Los Angeles here. Wanted to know 1. recommended ways to suppress growth of weeds through various Southern California seasons and 2. recommended approaches to hillside groundcover in order to a) reduce effects of erosion b) reduce maintenance over perilous (2:1 slope) ground.

I was told to use Roundup and allow the product to settle in for 7-days before turning the dirt over (excavation & earthwork). How to maintain a weed-free (decomposition of roots, plant material leaves pockets of air beneath grade. Water penetrates these cavities and settlement is the result) environment for the duration of a year-long project short of mannning the site with gas trimmers and manual labor (expensive). What is a good short-term and long term solution?

Overall finding from site soil report: Natural soils consisted of moderately compact, very fine to fine, slightly silty sand underlain by moderately compact to compact very fine to fine slightly silty sand and clean sand and fine to coarse slightly silty sand wit gravel and cobbles. No groudwater or seepage detected to 20'.

I have attached an image (weeds were recently trimmed - area shown represents 1/2 of area in question), of which a storm drain channel can be seen at the bottom of the slope. I wish to reduce runoff as much as possible. Currently have a silt fence of filter fiber paper (will prob go with sump pumps if need be) in place. How to use vegetation (I will be calling the shots regarding plant selection, just do not know what plants to select) to achieve goals of weed suppression and low maintenance. Have been advised to go with hydroseeding as a possiblity. Comments? Suggestions? Recommendations?

[cutntrim]

Originally posted by adamlau
Have been advised to go with hydroseeding as a possiblity. Comments? Suggestions? Recommendations?

Well, I'm a long way from California, but if that's 1/2 the area shown then that'd be a lot of planting. Around here they hydroseed the slopes alongside the major highways and I'd suggest looking into that.

[Mark Oomkes]

When I was in LA a few years ago, I saw a lot of Oenethera on banks just like this one. It appeared to be doing a great job of keeping weeds to a minimum and providing erosion control.

I don't think you're ever going to completely eliminate weeds, if that's what you're going for.

[AZTLANLC]

Around my area I would use cown vetch, I'm not sure that is a plant that can be grow in your area.