This is a better shot of the big picture.

{{gwi:34012}}

Lesson: don't amend your original question, because once it has an answer it gets knocked off the top of the list :-)

Anyway, to bump it back up, I'll say that I don't find your question quite clear. You are going to grass it all in after your cover crop, so it should be reasonably protected from erosion... but it sounds as if you are particularly concerned about the west side facing the espalier, yet you wonder if there should be retaining toward the south - I'm not clear on why that will help. And if you do a retaining wall, are you still just looking at grass? Or is that to bring down the level of the grass?

I know nothing about topsoil but it seems like a better thing to use as fill than whatever junk dirt is usually used. But I hope someone else chimes in there.

KarinL

If you have raised the soil level at the base of the espalier, you are putting the tree at serious risk. Even a couple of inches of additional soil can smother the roots and cause death. I would do whatever is necessary to remove any added soil and make sure the increased soil level is kept well clear of the espalier and its root system.

I think you answered your own question in the OP. You will need some kind of wall to hold up that soil just don't spoil the look with something cheap and nasty. The only problem with so much topsail other than the cost is sinking or settling so make sure this happens before the grass goes in.

The terrace will have a 4" metal edging.

Considering the depth of the added fill under the terrace -- as well as the added topsoil adjacent to it -- how deep should the metal edging be anchored?

[This is NC, so the zone is most likely 7a-8a.]

thank you for your feedback thus far. I don't fully understand how my posting will affect the order of its appearance but I want to respond to points raised.

The metal edging will be almost flush with the surface material on either side: sand rock and grass or planted bed. It is anchored with metal stakes.

I will do what I can to pull back the soil that got pushed over the apricot trees roots. I don't want it smothered!! I just planted it less than a year ago so the roots probably do not extend that far into the path yet.

I pulled some rustic looking cement block from the pile that was going to the dump. there is enough to build a low retaining wall that will extend from the corner of the house by the porch and then curve around to form the edge of the walkway that exits the west end of the terrace. When I build up more savings I can cover it (or face it) with stacked stone like the foundation of the old part of the house. The purpose of the retaining wall is to create a flat planting bed on the south side of the porch. Right now, when you are standing near that space it feels like the slope is too steep and "pushes" you into the side of the garage. It is not restful looking, if you know what I mean. The path from the terrace will curve and go through the space between the garage and the porch. It will meet up with the kitchen stairs.

I think I need more help from you all. You are so knowledgeable!!! I will rustle up some pics of the yard so you can help with the design of the paths (please!). I have so many questions! I also can scan and post a plan view from the architect that I drew paths on.

raro, when a thread is first posted, that thread shows up at the very top of the forum list. If there are multiple threads which have not yet been answered (no "follow-up" posts, in GW's terminology), they appear at the top in chronological order, with the newest first.

So threads which never get a "follow-up" post are listed first. If they never get a reply, eventually the software will bump them down; I don't remember how many days or weeks that takes. [When someone posts spam, we'll "answer" it so it sinks down on the list.]

By "answering" your own thread with a second post, you bumped it down below the threads which had never been replied to, and it was listed as having a "follow-up" post. Threads which have received at least one reply are listed in chronological order by the time of reply, with the most-recently-replied-to thread first.

As I don't clear my browser's most recent History, the threads I'm up-to-date with show up in purple, while those with posts I haven't seen show up in blue. So it doesn't matter much to me where a post is listed: I look at nearly everything that shows up as blue, though not always immediately. However, others might see a thread steadily accumulating "follow-ups," and not click on it: perhaps they're busy in RL, or that thread title doesn't sound like something they're interested in, or they already looked at the original post and either didn't have time to answer or didn't have much to say on the issue. In that situation, they'd notice the thread was accumulating "follow-ups" and would assume the OP's question was being answered. So they might never click on the thread to find out what was being said. So by "answering" your own thread, you might lower your chance of receiving answers!

Why not consider moving or replanting that single espallier. It's a lopsided design strategy to allow one plant, planted less than a year ago to dictate grades, erosion and drainage. Move (or lift the plant to a new grade) if that's what's needed. It's too easy to fall in love with one element to the detriment of an entire project.

I don't know apricots, but most small trees could be moved at this point and even if it could not, is that one tree really more important than the whole project?

Look at your overall design first and then, look at individual plants.

That is a good point Seaplant. I think that I have pulled away enough soil to fix the immediate threat. It turns out that it was not all that deep anyway. Not deep enough to thwart the maypops from coming up! The workers put in the low retaining wall and have begun installing the edge of the terrace and walkways. I will try to get some additional pics so that I can get some fresh advice with a clean slate from you gurus. If you feel strongly that the apricot must move, I can do that.