a tree is said to be 2 to 3 times as large.. underground.. as above ... ergo.. 15 feet is not far enough ...especially for a 40 foot tree ... and no tree stops growing at some magical height ...

IMHO ... dont do it.. too close ...

how abut a shrub or some such ...

ken

They DO stay close to the surface but they can spread out laterally a huge distance - the larger the tree, the further the spread. That said, I see septic systems installed in heavily wooded areas all the time, often with large growth conifers very close by. It can be done but it is easier to install the septic amongst existing trees than it is to plant one nearby and not have it invade the system. That offers a pretty rich growing environment most plants - trees included - love. And as much as septic systems cost to replace or repair, I'd avoid planting anything large within that 15' distance. The rule of thumb is plant as far away as the tree is likely to grow height-wise. So for an anticipated 40' tall tree, plant no closer than 40' from the septic field.

I just removed 6 white and black spruce that I had planted as 'seedlings' 15-20' from the end of my drain field. They were getting close to 6" dia. above the root flare and probably 15 ft. high. You could see the root system sticking half way out of the ground between the trees and the drain field. Surface roots send down feeders and when they find what they like, they put extra growth there. Most of the roots were between the trees and the drain field.

Consider using root killer every few years if you have a septic system with in reach of tree roots.

Wild conifer species all tend to get big. If you can drop the native requirement then there is a galaxy of dwarf and slow-growing garden conifers that could be chosen from. Including horticultural selections of eastern native conifer species.

no, no wall. But a wall would have to be completely non porous or roots will eventually penetrate.

It's very sandy where I'm talking about. Trees struggle to grow there. Remember, these trees were fairly young and only a fraction of there target height. And this was preventive maintenance as it was obvious what was happening.

I think that you should be good to go, if you were going to put a willow or poplar in that spot I'd recommend against it. IF anything it would just keep the fir a little happier.

From what you describe I'd recommend a pine. I had read recently that their roots are perhaps a little more septic friendly. I actually planted a pinus parviflora 'blue giant' maybe 20 feet from my field. It's a handsome little guy...Fingers crossed it works out lol.

John, I wouldn't worry as the end of your septic field is rarely "used" as most of the drainage occurs at the area nearest the tank. IMO, 15' ft away would be fine. My septic field in the VA woods had mature oaks & hickories surrounding it, some closer than 15', and never had an issue for 25 yrs. And conifers typically are mostly surface-rooted, not deep-rooted (look at the root-crown of uprooted, windblown conifers).

Canaan fir grows rapidly. I don't have the best of soils but I have a lot of Canaan firs... the largest in the best soil on my property are putting on 18" a year. They were planted as 12-18" seedlings in 2008. Of those putting on the most growth today, I'd estimate 12-15' on those specimens.

You might consider Pinus koraiensis. That's the rate of speed you're looking for. They grow 9" a year consistently when well-rooted and slower until they reach establishment.

Dax

'And conifers typically are mostly surface-rooted, not deep-rooted (look at the root-crown of uprooted, windblown conifers).'

And how deep are your drain fields? My pipes are exactly 2' down on top of a layer of rocks. With most mound systems are on top of the ground.

I'm sure the type of soil dictates how far roots will travel with heavier clays limiting root distance more than coarser soils.

I'm not trying to talk anyone out of anything but root problems are pretty common with septic systems and our zoning officials warn of having trees too close. Maybe you want to check with you local zoning and see what they recommend. I'm sure it varies with locations.

Burnt Ridge Nursery has 1-gallons for 14$

Burnt Ridge Nursery

Forest Farm has 4-5' trees for 75$ + an oversized shipping cost.

Forestfarm

I googled Pinus koraiensis for sale. Looks like those are the two US sources only.

Dax

I definitely agree, Bill.

Dax

Material on the market here as Pinus strobus 'Nana' often throws up one or more leaders and forms itself into a small tree. Older ones you would never know started out as a round bush.

All trees not growing in deserts form a pancake of shallow roots, whether or not there is a percentage of anchorage roots that go deeper. Roots need air, if a species is not aquatic the majority of roots are near the surface, where the air is.

A drain field is full of air. Roots will go down in the ditches full of drain rock, moisture, and nutrients that make up the drain field. However, I don't think pines, firs, and spruces would be much of a problem in your case.

I would think the trees to avoid are the ones that form fibrous root systems like Populus, Thuja, and Sequoia sempervirens.

I saw a large Cottonwood at the end of a drain field go all the way up the drain field and into the septic tank before the homeowners couldn't flush their toilets. The roots were blocking the exit to the tank. What an expensive mess!

55 year drain field surrounded by 45 year old White and Norway spruce...no issues. Most conifers are intolerant of saturated conditions and the roots will not grow into saturated soils.

Maybe I'm just a worry wart, of coarse black spruce likes it wet, very wet, with nutrients even better. John, if that wall is a true barrier, you shouldn't have a problem.

Native to where?

I like weeping white pine.

Sounds like a nice spot! Can't comment on the 'native' part being I have no idea. :^) Let us know how things turn out.

I'm surprised to hear people suggesting pines. I always read that they're one of the worst choices near septic fields. I think I'll stick with Canaan Fir for now as it serves my needs and is the smallest growing of the native firs of eastern USA. speaking of which, Colin, by native, I mean anything in my general region...east coast, hilly appalachia style terrain. I'm in northwest NJ in a rural-suburban wooded area near a lake.

'I'm surprised to hear people suggesting pines' Maybe a smaller cultivar? I know when we first dug water wells on this place, we were bringing up pieces of Jack & Red pine roots from +16' down.

Someone wrote in a pervious comment not to plant a tree that likes saturated soils, and Canaan Fir sometimes grows in wet soils. Check out this post.

http://forums.gardenweb.com/discussions/1827314/abies-balsamea-v-phanerolepis-canaan-fir-pictures?n=8

Yikes...this is why I asked about root habits. Thanks! Does anyone know if Canaan Fir like dry soil but TOLERATE wet soil, or if they seek out and actively prefer wet soil?

What did you end up planting? Similar question but for zone 5b and trying to keep our neighbors with a leachfield 12-15’ away comfortable while still getting the conifer/pine needle look I like...