Deformation under spawned object

[DerPapa]

Hi
I'm new to tyflow and I want to do a certain thing, but I can't figure it out.

I want to spread some object on an objects surface, like trees. At the same time I want a deformation right at the place where I spawn the objects.
Kinda like in the attached mockup (which I modelled)

I was investigating into tyParticleskin, but my problem is: How to seperate the particles I need to place the trees, from the one I need around the trees, which are needed in the skinning to keep the floor geo to its base level.

But maybe there is another way to do it?

Help, or a hint into the right direction  is greatly appretiated
thanks
Michael

[d4rk3lf]

You can clone the ground (so you brake independence from the ground you spawned particles), and just use Tyselect to select parts of the ground that are touching the particles. 
Attaching you a sample file.

[DerPapa]

You can clone the ground (so you brake independence from the ground you spawned particles), and just use Tyselect to select parts of the ground that are touching the particles. 
Attaching you a sample file.

Man! Thanks a lot! 
Right now I'm using a Vray Displacement Modifier with a distance tex as a work around. didn't know tyselect is a thing

cheers
Michael