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we need to ID the trees...

tilling will simply encourage the trees to regrow new feeder roots...

it will not solve your problem ...

what are you thinking about planting there ...

ken

Not sure what type of trees these are. I wanted to plant some boxwood and peony to start.

"Trunk diameter is a much better predictor of root spread.
Trunk diameter is about as good as it gets for estimating root spread
of unobstructed trees. For young trees [less than approximately 8 in
(20 cm) in diameter], the ratio of root radius to trunk diameter in
the documented studies was about 38 to 1. That is to say, a 6 in
(15 cm) diameter tree can have a root system that extends nearly 6 m,
or 19.7 ft out from the trunk (about 19 ft per 6 in). "

Planting near already established trees as you are discovering, can be difficult. Is there somewhere else you can put your plants?

Here is a link that might be useful: more about tree roots than you probably want to know

Not really. Perhaps I'm stuck just smoothing the dirt and putting mulch on top. I can always landscape with rocks/boulders and annuals. I was just hoping these were leftover shrub roots.

Some trees, like birch or maple, have surface feeder roots that suck all nutrients and water from the soil and make it nearly impossible for most plants to flourish. Others, like oak and sycamore are great to plant under. But in no case would a peony want to be under a tree; they prefer full sun. Most boxwoods would tolerate some shade, but are not really shade plants.

Also, one does not till under trees to plant a shade garden. Just start planting. But by all means, plant appropriate plants. The list of plants for shade is enormous; look up some and start there.

I can't iD the trees, but that root matrix is very common for maples. We had red maples in our front and could not grow much under them.

I wonder if helleborus could compete.

At least some of your trees look like red maples (the ones closest to the buildings), so I would give up on planting things under them unless they are in pots raised off the ground. When I had pots set onto the ground the maple roots grew up into the pots. If you want to plant shrubs or perennials in the pots, they should be at least 2 zones colder as far as hardiness.

I just want to stress this (as written above, thank you):

"Also, one does not till under trees to plant a shade garden. Just start planting. But by all means, plant appropriate plants. The list of plants for shade is enormous; look up some and start there."

This is the best advice for underplanting trees. I started with a blank slate 25 years ago, and we are now doing the shade part. Just dig a hole and plant your shrubs, perennials, etc. They will need water for the first 2 years when it is dry, then they should be all right. Most shade tolerant plants evolved to live in a tangled root zone.

Thank you Thank you Thank you EVERYONE :)