I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I don't know what your soil conditions are, but we have several slopes like
that around our place. I just covered them with bark dust and let the
natural vegetation grow. Digging in little terraces, planting trees, and
placing boulders here and there could help naturalize and stabilize the
hillside as well.

Many years ago, we terraced a hillside at our old apartment using railroad
ties. The cost wasn't too bad, and they worked rather well. But, ties seem
to be harder to find now than they were 20 years ago. You could do the same
thing with pressure treated 6x6 timbers, but the cost would be higher.

The cement blocks designed for wall building seem to be very popular,
sturdy, and easy to install. Most home centers will deliver to your site
(for a fee), so hauling them shouldn't be too much of an issue. Assuming,
of course, the truck can get to your site.

Take care,

Anthony

wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I would definitely opt for wood here. Where I live (Belgium), it is
common practice to use flexible azobe strips (1/4" or 1/2" x 4") and
matching poles (1x1" up to 2x3" depending on length) for retaining
walls. You can also get panels from woven strips.
Azobe is strong, has a natural look and it lasts a life time (unlike
your steel bars).

Koen

wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to

Is that the entire slope, or just the portion on your property? ie, are
you on the top or bottom of a mountain?

it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

That is a pretty large piece of ground to rearrange. Is there erosion
now? Gullies? What is at bottom of slope? Where is your house in
relation to the slope? Soil type? Trees? Native plants? If you are
just dealing with a graded part of a building lot with a few bare spots,
I'd fill in the washed out soil first. Plant something with good root
system. Laying down a little flagstone with landscape cloth behind it
would help keep soil in place til plants fill in. I would consider
taking some photos to county ag extension service - they should be able
to offer advice (free) and give tips on what to plant that doesn't
require high maintenance.

If I understand the message right, the area in question is about 15x70.
New plants with shredded cypress mulch can hold soil just fine. Mondo
grass is one plant that is great for Florida, but we don't have
hillsides to worry about. it is a plant that is attractive, doesn't
require any particular care, and won't take over the landscape. A plant
like that, across a slope, would do a lot to slow runoff and erosion.

reslope a little so its closer to the angle of natural repose. avid
building walls etc they always eventually fail.

with the right planting you will ave success,

stuff like ivy, crownvetch, look along local highway slopes, note road
dept avoids building walls since they become maintence issue.

In article ,
says...
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I don't know what your soil conditions are, but we have several slopes like
that around our place. I just covered them with bark dust and let the
natural vegetation grow. Digging in little terraces, planting trees, and
placing boulders here and there could help naturalize and stabilize the
hillside as well.

Many years ago, we terraced a hillside at our old apartment using railroad
ties. The cost wasn't too bad, and they worked rather well. But, ties seem
to be harder to find now than they were 20 years ago. You could do the same
thing with pressure treated 6x6 timbers, but the cost would be higher.

The cement blocks designed for wall building seem to be very popular,
sturdy, and easy to install. Most home centers will deliver to your site
(for a fee), so hauling them shouldn't be too much of an issue. Assuming,
of course, the truck can get to your site.

Take care,

Anthony

Thanks for that input. We're on a regular street but it'd be a lot of
hauling to get block back there...it's a lot of block. But maybe that's
the way to go. The hill was grassy till last year when a gopher colony
took root, and they've been accelerating the 'slide' of the hill. I
wiped them out last year but they've returned. So looking for a way to
mitigate the effects of the loose dirt the push out.

In article .com,
says...

wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I would definitely opt for wood here. Where I live (Belgium), it is
common practice to use flexible azobe strips (1/4" or 1/2" x 4") and
matching poles (1x1" up to 2x3" depending on length) for retaining
walls. You can also get panels from woven strips.
Azobe is strong, has a natural look and it lasts a life time (unlike
your steel bars).

Koen


That sounds like good wood, but here in California I don't think it's
available. 4" tall strips and that thin would be hard to make work in a
1' tall wall though? We have redwood of course but quite expensive these
days, and the 2" thickness that I'd probably need to use might not curve
along the hillside contours very well.

Yes that's the entire slope. Our property (1/2 acre) was graded 50 years
ago so that part of the slope became flat and downhill form that became
steeper than the natural hillside...so the slope does continue at the
bottom of my problem area, but that continuing slope is 'safe'. This is
Califorina, the soil is clayish I believe. House is above the slope, but
the flattened area is a good 20' wide, here is no immdeidate danger of
it being involved in the 'overslope' erosion...but I don't want to lose
the hillside at all if possible.

There are no gullies etc. The hill was grassy (with a few bushes) till
last year when a gopher colony took root, and they've been accelerating
the 'slide' of the hill. I wiped them out last year but they've
returned. So looking for a way to mitigate the effects of the loose dirt
they push out. They put out so much dirt last summer than this year the
grass didn't return with the winter rains as it usually does...so all
summer the slope was mostly just exposed dirt. The new gophers are less
numerous but it seems to be shaping up into a continuous battle, they're
not easy to get.

I'm not sure if there are any ag stations around here, the is the east
bay part of the SF Bay Area. I may have to resort to some professional
type, though some I've talked to seem fairly clueless. It's not quite
the situation for a real retaining wall but that's the "regular" thing
to do...so I hear that.

Re plantings, I know that would help. But in my case, with gophers
pushing out finely granulated soil, I think I need something like this
terracing idea to keep the soil from sliding down the hill...it's just
at the slope where gravity takes over.

In article .net,
says...
wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to

Is that the entire slope, or just the portion on your property? ie, are
you on the top or bottom of a mountain?

it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

That is a pretty large piece of ground to rearrange. Is there erosion
now? Gullies? What is at bottom of slope? Where is your house in
relation to the slope? Soil type? Trees? Native plants? If you are
just dealing with a graded part of a building lot with a few bare spots,
I'd fill in the washed out soil first. Plant something with good root
system. Laying down a little flagstone with landscape cloth behind it
would help keep soil in place til plants fill in. I would consider
taking some photos to county ag extension service - they should be able
to offer advice (free) and give tips on what to plant that doesn't
require high maintenance.

If I understand the message right, the area in question is about 15x70.
New plants with shredded cypress mulch can hold soil just fine. Mondo
grass is one plant that is great for Florida, but we don't have
hillsides to worry about. it is a plant that is attractive, doesn't
require any particular care, and won't take over the landscape. A plant
like that, across a slope, would do a lot to slow runoff and erosion.

wheel wrote:
In article .com,
says...

wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying that
right, slope goes down a two feet for every three out). The main goal
here is to forestall erosion, secondary to help plantings take root.
Hillside is about 70' wide, and it drops 10'. It has a mild contour to
it, so straight terracing wouldn't be ideal. Anyone have ideas re a good
material for the 'retaining walls'. I'm not really aiming at a full
strength retaining wall system which would probably cost a fortune to
install. More hoping that some easy going terracing will do enough.
Like, steel pegs knocked in two feet deep, with 1 foot up, and some
barrier material as the wall...what that would be I don't know, but have
wondered if there is some recycled plastic 3/4" x 1' king sized
benderboard material out there. Or are there 'systems' for this type of
situation? I'm not eager to use the cement blocks that are common, too
much weight to haul, it'd be a lot of block. There is no snow or
freezing where I live.

I would definitely opt for wood here. Where I live (Belgium), it is
common practice to use flexible azobe strips (1/4" or 1/2" x 4") and
matching poles (1x1" up to 2x3" depending on length) for retaining
walls. You can also get panels from woven strips.
Azobe is strong, has a natural look and it lasts a life time (unlike
your steel bars).

Koen


That sounds like good wood, but here in California I don't think it's
available. 4" tall strips and that thin would be hard to make work in a
1' tall wall though?

You would be surprised of this. I've seen 1/4" thick strips been used
for retaining walls or even river banks up to 3' high. Supporting poles
are typically placed 20" apart.

We have redwood of course but quite expensive these
days, and the 2" thickness that I'd probably need to use might not curve
along the hillside contours very well.

It's also known as Ekki or Bongossi so you may want to check with a
local supplier specialized in hardwood or wood for garden use.
Here's a link (with extra info on the wood's qualities) for a Canadian
supplier: http://www3.sympatico.ca/tmt/index.htm (I guess you should be
able to get it in the US too.)

I find it reasonably cheap at US$ 10 for a 1' x 10' panel at my local
supplier.

Greetings,

Koen

We're on a regular street but it'd be a lot of hauling
to get block back there.

We just installed a concrete paver patio. When Lowes delivered our pavers,
they had an all-terrain looking forklift. They set the pallets of pavers
right next to where we were working.

Assuming you have enough width for the forklift, and there aren't any major
obstacles, they could probably deliver the stones right next to your hill.
Worth checking with them if you want to go that route.

The hill was grassy till last year when a gopher colony took root
I wiped them out last year but they've returned.

Hmm... I wonder if the gophers would cause problems with a terraced
hillside as well? I would think they would push dirt right over the terrace
onto the next level? Getting rid of the gophers sounds like a bigger
problem...

looking for a way to mitigate the effects of the loose dirt the push out.

Cover the hillside in rocks too big for them to push up, or encapsulate the
whole hillside with concrete?

Anthony

That sounds like good wood, but here in California I don't think it's
available. 4" tall strips and that thin would be hard to make work in
a 1' tall wall though? We have redwood of course but quite expensive
these days, and the 2" thickness that I'd probably need to use might
not curve along the hillside contours very well.

I wonder if those synthetic deck boards would work? They're more flexible
than wood, and aren't supposed to rot.

Anthony

According to HerHusband :
That sounds like good wood, but here in California I don't think it's
available. 4" tall strips and that thin would be hard to make work in
a 1' tall wall though? We have redwood of course but quite expensive
these days, and the 2" thickness that I'd probably need to use might
not curve along the hillside contours very well.

I wonder if those synthetic deck boards would work? They're more flexible
than wood, and aren't supposed to rot.

I'd expect them to slowly bow out further as long as the dirt
was pushing on them.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

50 year old slope sounds $Approximately$ stable, especially with the 20' buffer below.
i think you could do this with plantings. i approx agree with norminn and hallerb (person who replied in parallel reply), most
of the others...

find a plant oriented reveg/erosion company that doesn't restrict themselves to only natives (an inexact term of course)

or you could hire me for a cheap list of tough plants. they won't all survive the gophers, but some of the species will annoy
your gophers. you can then fill the dieoffs with the survivor species. this requires a lot less work than "construction".

i live near mt. diablo. 20 years and not counting. :-)

I will try 'pinging' recent group of your posting, because your newsgroup address looks very fake:
wheel in
.net:

Yes that's the entire slope. Our property (1/2 acre) was graded 50
years ago so that part of the slope became flat and downhill form that
became steeper than the natural hillside...so the slope does continue
at the bottom of my problem area, but that continuing slope is 'safe'.
This is Califorina, the soil is clayish I believe. House is above the
slope, but the flattened area is a good 20' wide, here is no
immdeidate danger of it being involved in the 'overslope'
erosion...but I don't want to lose the hillside at all if possible.

There are no gullies etc.

needed only when drainage needs fixing.

The hill was grassy (with a few bushes) till

usually baccharis on sunny "never planted" clay.
other shrubs mix in as you go more toward the coast (bollinger cyn, castro valley, oakland hills) and northfacing.

last year when a gopher colony took root, and they've been
accelerating the 'slide' of the hill. I wiped them out last year but
they've returned. So looking for a way to mitigate the effects of the
loose dirt they push out. They put out so much dirt last summer than
this year the grass didn't return with the winter rains as it usually
does...so all summer the slope was mostly just exposed dirt. The new
gophers are less numerous but it seems to be shaping up into a
continuous battle, they're not easy to get.

I'm not sure if there are any ag stations around here, the is the east
bay part of the SF Bay Area. I may have to resort to some professional
type, though some I've talked to seem fairly clueless.

dealing with marketing , construction, marketing , and marketing issues leaves no time for plant (knowledge) :-)

It's not quite
the situation for a real retaining wall but that's the "regular" thing
to do...so I hear that.

Re plantings, I know that would help. But in my case, with gophers
pushing out finely granulated soil, I think I need something like this
terracing idea to keep the soil from sliding down the hill...it's just
at the slope where gravity takes over.

In article .net,
says...
wheel wrote:
I have to deal with a hillside that has a 2:3 slope (if I'm saying
that right, slope goes down a two feet for every three out). The
main goal here is to forestall erosion, secondary to help plantings
take root. Hillside is about 70' wide, and it drops 10'. It has a
mild contour to

Is that the entire slope, or just the portion on your property? ie,
are you on the top or bottom of a mountain?

it, so straight terracing wouldn't be ideal. Anyone have ideas re a
good material for the 'retaining walls'. I'm not really aiming at a
full strength retaining wall system which would probably cost a
fortune to install. More hoping that some easy going terracing will
do enough. Like, steel pegs knocked in two feet deep, with 1 foot
up, and some barrier material as the wall...what that would be I
don't know, but have wondered if there is some recycled plastic
3/4" x 1' king sized benderboard material out there. Or are there
'systems' for this type of situation? I'm not eager to use the
cement blocks that are common, too much weight to haul, it'd be a
lot of block. There is no snow or freezing where I live.

That is a pretty large piece of ground to rearrange. Is there
erosion now? Gullies? What is at bottom of slope? Where is your
house in relation to the slope? Soil type? Trees? Native plants?
If you are just dealing with a graded part of a building lot with a
few bare spots, I'd fill in the washed out soil first. Plant
something with good root system. Laying down a little flagstone with
landscape cloth behind it would help keep soil in place til plants
fill in. I would consider taking some photos to county ag extension
service - they should be able to offer advice (free) and give tips on
what to plant that doesn't require high maintenance.

Mother Earth News had an article many years ago (20+) where they used
tires to terrace a hillside. I ran across your question in searching for
more information about how this was done. I would think that the tires
would be held together (bolts possibly) and I know that they were
staggered such that they had a “reveal” that would hold vegetation. The
next row was offset (side to side) as well as back into the hill and dirt
was packed into the tire/open spaces that were created by this offset.
Then plants were planted in the open spaces. Looked much like a pattern
of window boxes or planters going up the hill. The tires would hold heat
in the spring, which may be helpful but would do the same in the summer
and may cause problems with tender plants. Don’t know how your gophers
would react to this method. I believe that there are plants that they do
not like and will avoid. As one person said, check with your county
extension agent. Also seeing that you live in CA it may be a problem
dealing with your neighbors when you mention tires and landscaping. I am
still looking for more information on terracing with tires and will
forward any good information I find.

Alan

We live in the west of england and part of our back garden is a 100 year
disused sandstone quarry, surrounded by mature woodland, at the foot of
large hill with a similar angled unstable slope to yours. Elms had grown
abundantly to about 20' and succumbed to the Dutch disease. We cut them
down, removed the diseased tops and branches and burnt them. Then we laid
the trunks horizontally behind conveniently placed 2' high stumps,
occasionally driving in stakes, so that a flowing flattish spiral (can you
picture that?) terrace follows the line of existing rock outcrops up to a
top outlook. We then backfilled with loose surface rocks and topped off
with the leaf mulch and black topsoil. Planting is traditional with some
water features being introduced.
We dont expect either the stumps or trunks to last forever, but hope (!)
that when they decay, the landscape will have compressed and stabilised
with the help of the new root systems and be self supporting. Watch this
space for the next 50 years.
One thing we would ask, think hard before using man made materials unless
absolutely unavoidable. It might sound a bit hippy, but theres enough
concrete and plastic out there in the modern world, without having it all
around you in your private haven.

I just re read our message and it appears that the elms had grown to 20
inches and the stumps were 2 inches high. This, of couse, should read
feet, although Im sure it was invaluable advice for any unstable bonsai
gardeners.