I will be eager to hear from those more experienced and knowledgeable than I am.

Don't replace your mulch. The decayed organic matter is what makes humus, which is an ingredient of loamy soil.

In my experience, no matter how much you raise the beds and how well you prepare the soil, the trees will invade. You can enjoy it for a year or two before the trees take over.

I prepared a raised bed (only 10 inches) but first dug out all the roots within a shovel depth. I was far enough out from the nearest tree that I didn't think I would hurt any of the trees by doing it. That was two years ago and the trees are already taking every bit of water that I supply, worse this year because of the drought. I have oaks, but maples are worse I think.

I once had a silver maple come up through a crack in the concrete patio and into a whiskey barrel through the bottom drain hole. When the barrel finally burst, it was a solid ball of maple roots.

I have decided that all the ferny woodland gardens are in areas of the country with ample rainfall, or belong to people with ample budgets.

This summer I collected seeds from things that have made themselves at home in the woods, under oaks, in dry rocky clay. Unfortunately they tend to not be very spectacular. Native grass and "pussy toes" and virginia creeper and wild blackberry and poison ivy, and some wild "beautyberry" that looked dismal by the end of summer. Fragrant sumac survives drought and part shade. It can have nice fall color but probably not this year. A floral exception is butterfly pea. It bloomed in the woods with no supplemental water. Granted, it was about 40 ft downhill from the septic tank leach field. Come to think of it, I don't think it bloomed anywhere else.

I suggest you find some woods near where you live, and hike at different seasons. Take pictures and identify things that appeal to you. Then try to find improved cultivars.

A recommended book is "Start with the Soil" by Grace Gershuny. Another is "Noah's Garden" by Sara Stein. The latter is a more enjoyable read, although the details can't be extrapolated to this part of the country. Ms. Stein is big on blueberries. I asked once about growing them around here and the response was "you're nuts".

Erin, I would agree with Barton. Don't remove that old mulch. You want it to rot and make loam. If your soil is heavy clay you can add some sand, which might help break it up a bit. But most important of all is that you add lots and lots of organic material, and try to keep it from going powder dry. You'll have to research the individual kinds of plants you want to grow, for suitability to your climate. But I doubt you can go wrong by mulching and mulching!

George
Tahlequah, OK

Don't put to much soil over your trees roots. You will rob them of air, and could cripple the tree.

I would not remove the mulch either. Just add more, as it decomposes.

To make your clay like soil more fertile, add lots and lots of organic matter.

Don't forget to get your soil tested. Best way by far to find out what nutrients it needs.

Do you know, how to gather soil for a sample?

Moni

Thanks for the help. Is there any circumstance in which I should remove old mulch (from other beds)? When I began reclaiming the overgrown area under the tree this summer, I laid down landscape cloth to help after I dug it out. Is that an expense I can omit in the future?

I never considered how complicated it could be to plant under a tree...did I mention I was a novice? Barton's story of the whiskey barrel was a real jaw-dropper...I shared that one with DH.

The bad news is I already planted (dug 2'and raised 1/2') two Endless Summer Hydrangeas about 5-6' from the trunk. The good news is I bought them for 1$ on clearance so I'm only out the work (and was it work!)

It is a great idea to collect indiginous plants...I'm just beginning to explore seed collecting, and though I am enthusiastic about it, I am still quite clumsy in executing the process start to finish. I also really appreciate the recommendation for the books. I like having resources books like that, but am wary of buying a book with pretty pictures, but no content. I have been online already trying to hunt Gershuny's book...it looks perfect!

Moni: It is funny you should ask about soil testing. I have recently visited with my next door neighbor who tested his this summer. His lawn was extremely acidic. My soil appears to be quite anemic and I can't wait to hear what the experts have to say about it. Unfortunately that's a project for another day...where does all the time go?

Best Wishes,
Erin

You can find just about any book at alibris.com. It's my favorite.

My husband relocated his Endless Summer hydrangeas from his raised bed under trees, to a spot near the porch that gets north and east exposure. He waited almost too long, they were about to pass over into their "Eternal Summer" when he moved them. They are already blooming in their new home, a long way from the nearest tree.

His trees have survived the abuse of the extra soil (so far.) But the plants in the beds are struggling.

There is a blackjack near my veggie garden that will soon be firewood. The trees west of my veggies help protect them from the hot afternoon sun and west wind. My plan is to let the smaller ones grow and harvest the bigger ones for the fireplace.