Actually, they are all trees unless you get smaller cultivars. Have you got a pic or two of the area?

tj

The bald areas on the spruces are probably due to bugs or blights rather than shading. So that if you determined what specifically was happening it would become possible to undertake control measures that would enable the trees to refurnish any of these branches that are not dead all the way out to the ends. Also if not interrupted and corrected the condition is likely to increase in extent.

In addition any plants - regardless of kind - jammed in underneath evergreen conifers that are not large and high branching (as in an old growth forest) are going to have a very tough time of it. So that the same dense, attractive growth that would result from placement in a better spot is not going to be produced even if the added plants are shade tolerant kinds.

Also there is the mechanical problem of trying to dig planting holes among the roots of closely planted existing trees.

Now if you have the room to plant well in front of the existing trees instead of beneath them then that is different.

thank u very much both of u, here r pics of the area. the one with fuller trees is to the left of a 60-70 ft sugar maple in the center of the back yard, the thin part is to the right of this sugar maple. there is a water tower behind our property that u can see there. the maple has a large canopy that leads to filtered sun in that area, although i believe from noon to about 4pm the sun hits that spot. we had an arborist suggest just planting norway spruce again and our landscaper rec green giants which we have for a wall to the road at another part of our lawn. any recommendations r appreciated i just want to block out the fence and then have some thick wall eventually come in similar to what is on the left

Balding of spruces in first shot looks like a blight or bug problem as suspected. Anyway plant what you like in front of them and not beneath the maple, remove the spruces after this new addition is as big as they are. Noting that Leyland cypress has disease problems in the East and eastern hemlock is being hammered by adelgid insects. Leaving of the three you mentioned the 'Green Giant'. Which should be fine given enough light. Unless you have deer there.

thank u, is blight or bugs curable and why hasn’t it spread to the other spruces? are there any alternatives to eastern hemlock that can grow in shade? the arborist that reviewed the trees said spruces chase the sun so it’s not unusual to see bald branches in a partial shade setting.

Look at Holly trees and Chamaecyparis before putting in more spruce. And no you can't put them 2-3 feet apart for thickness. That close spacing will lead to thinness.

if you insist on working solely at the property line.. and with all the shade back there.. i think you are going to be very frustrated for a very long time.. if in fact you cant grow some new trees back there .. with any vigor ...

imo... shade is why your conifers are wispy ... they are full sun plants .. yes there could be other issue .. but sans those potential issues.. there is still not enough sun ..

sooo .. if you plant more things in not enough sun .. they will take longer to establish.. may never perform to annual growth expectations.. and will probably etoliate like these have over the last 20 years or so ...

if you get rid of the maple... you will probably have better result.. but taking away that canopy.. will make the water tower come into view ...

but along the same idea ... a couple more smaller trees out from the property line toward the house ... will make it all disappear ... and they will grow with vigor in more sun ...

my usual recommendation is redbud ...

ken

thank u for helping set expectations. we had a 60ft elm on the left side of the second pic where those two small shrubs are located. that tree had a lot of nice coverage and obscured the tower so maybe we should grow a large tree there instead. and then do some basic shrubs to cover the fence in the blighted area.