It could have a significant impact. It is well established that clear cutting in the timber industry - essentially what you are doing but on a smaller scale - can have a profound impact on both water movement and soil erosion. But you would need a soils engineer to investigate your situation specifically and what kind of bearing it would have on your property.

There can also be a concern about tree removal leaving the remaining trees even more vulnerable to winds and blow down. That is of particular concern in my area with many very densely growing tall native conifers. They act as a windbreak or support system grouped together but lose that ability when thinned or heavily removed. That may be less of an issue with spreading canopy broadleaved trees but worth asking a consulting arborist about.

My initial concern would be with surface runoff and drainage. You will want to ensure that there is positive surface drainage away from and around all building sites. This will be much more of a concern in a cleared area, so carefully check the contours and gradients in your building areas.

If you have concerns about the bearing capacity of your soils, the clay content and expansiveness, or other subsurface issues you should have a geotechnical engineer (soils engineer) analyze samples in all of your building areas and make recommendations for proper foundation design and foundation drainage systems.

Good luck on your project.

Thanks for the responses. My house will have a slab. We had planned on a basement but scrapped the plan to save money. Will have a finished attic with shed dormer. Detached garage on slab with footings as well.

You'll have to get to stable soils for building anyway, stripping the top.

You should manage the stormwater, and plan for drainage AROUND your build site. We cleared about 3/4 to 1 acre on a gentle slope, flattened the area using cut / fill and retaining walls and worked hard to manage the water both ON the site and AROUND the site.

I agree a 1000% about making sure no trees can fall and hurt either a person or your home.

I would not be worried about removing 1.2 acres. I just cleared twice that much. Hundreds of trees. It is critical that your excavator is skilled and has the proper tools and lasers and experience to get that land to flow away from your home. Not hard to do for a true expert. They can do tricks with the contours. Slope it back gracefully without the eye even picking it up. Only the laser know the truth.

I loved our tree clearing guys. He had a big ole bumper sticker on his truck that said, " Don't worry, I hugged it first!"

155 acres is a dream come true.

You might consider going lighter on the east and west sides, especially with measurable amounts of unshaded fenestration.

In addition to what gardengal mentioned, root systems in forests grow to be intertwined, so when trees are cleared and the stumps and roots are removed, the roofs of the trees at the edge of your clear cut will be compromised. No matter what your wind patterns or the density of the canopy may be or whether your forest is evergreen or deciduous, you will likely lose additional trees. Some people leave stumps at the edge of the remaining trees, allowing those roots to decay slowly and hopefully protect the trees you want to keep.

A forester specializing in trees native to your area is your best bet. Don't count on your builder to know who this would be or to have any clue or to even care. Our builder thought I was nuts when I put up safety fencing to keep trucks away from the roots of two giant firs, but seeing their carelessness elsewhere on our land, I am so glad I did.

A 6000sf house forgoing a basement for a slab “to save money” already has skewed priorities. Creating a water management plan for all of the runoff created from the introduction of so many I’m pervious surfaces and lack of forestation had better be high on the list of things to NOT cut due to the budget. Otherwise the whole family complex shebang could just slide down the hill.

Perhaps "slab" was the wrong description on my part. We have a normal foundation that is 8 courses around and I believe that is sufficient for our job. It's almost enough for a basement. If you'd like to pay the roughly $75k to $100k extra for a full basement for me, I'll accept the donation. There are many large homes without a full basement. The builder already has a water management plan that is required by code.

Wayne I built my house on a block foundation. 5 block high and poured I totally think you made a great choice and saved $$$ Smart Move!

Multiple thoughts:

-With this much land, you should investigate a "forestry plan" with your county government. You have to jump through some hoops to get it started, but it can SIGNIFICANTLY decrease your taxes. In my area, I'm thinking you have to have something like 25 acres minimum, but I'm sure you'd qualify. We actively farm our land, so we have something similar ... I pay about $400/year in property taxes, and that's for 45 acres.

- You might consider calling in a timbering company to see if they'd like to cut /buy the trees in the area you plan to clear. Yes, they will push you to let them cut the whole area, but you know how to say "No", don't you? They'd do some of the clearing AND pay you for it.

- I do agree with the above poster that clearing 1-2 acres of forestry
will affect the trees that remain ... but mature trees are awfully tough
things. If a few on the border of clearing-forest are affected ... eh,
so what? If you were building on one acre and wanted to keep 2-3 lovely existing trees, it'd be one thing ... but with 153 acres of trees left, any one tree isn't exactly a precious commodity.

- 6000 sf house ... do you really want to put in the time and money to maintain, clean, heat/cool this much space?

- It's absolutely normal to be afraid of a tragedy repeating itself, but trees don't fall on houses and kill people on a regular basis. The last time I heard of such a thing was when Hurricane Hugo came through.

- With no trees near the house, shade may be an issue. You should think about this when you're planning overhangs and/or porches.

- Not all areas are good for basements. Here, where I live, no one has a basement. No one, and it's not about money.

A blog post from Scientific American that might be of interest,

Why Do Trees Topple in a Storm?

Appreciate the responses. The 153 acres is already in our local land use program and I will lose only 1 acre to the program so the other remaining acres will remain in the land use program. Part of the back part of the land was clear cut and/or select cut about 10 years ago and re-planed under a forestry plan under the previous owner. I have all of their records.

The storm that came through here recently and blew the tree over that killed the 9 year old was an "out of the blue" wind storm that lasted here for about 24 hours. I drove by the house that had the tree down and it was directly near the house, for shade I trust, and was a huge tree. Our currently house is surrounded by trees and I know it's a rare event, but to see them swaying and moving with every storm and fearing that it could fall down still concerns me. When I walk through the 153 acres now, it is not at all unusual to come across many trees that are laying down. They could just as easily fall on the house. At this stage, I would not be talked into keeping trees around the house.

The house is already designed and is ready to be built. We have a covered porch on the rear, covered "farm style" front, and a covered side porch. We'll need to rely on that for shade and some other things we have in the plans. I could go on but it is "mission creep" beyond my initial question so I'l hold off. Thanks.

In my heavily regulated county, any soil disturbance over 2,000 square feet requires an engineered targeted drainage plan for storm water. Is that not required where you live? It might not be a bad idea to look into anyway, so you make sure that you're not going to have problems down the road.

Oh, and I don't blame you on not wanting trees around the house. My last home was surrounded by HUGE mature trees. Every time we had a wind storm (which happens a lot in the PNW) I would be filled with anxiety.

We are building a home on aprox 12,000 sq ft lot that was fully treed. They chopped up most of the trees and roots and left them laying in the yard while hauling off most of the large trees. My question is with all of the mulched up trees and roots left in the ground will anything grow if planted. Like trees bushes, plants and sod? Please help, I don't think the builder is going to clean it up. They say they won't hurt anything.