Tell me how to kill a mature spruce tree.

[Steven A.]

I have 5,  30 year old spruce trees growing right on top of a 30 year old steel septic tank and drainfield at my elderly mothers home. The tank is near the end of its life most likely and I want to take the trees out before the tank fails so I don't have an emergency logging project and a failed tank to deal with at the same time.
She will not let me cut the trees unless they are dead. There is no other place to put a new tank or drainfield. She does have 50 or so more trees on her 4 acres so its not as though she will be living in a desert after they are cut.
You  can see my problem.

I have cut around the trunks with a chainsaw and also drilled a few 3/8 inch holes into the center of the trunks and squirted in some tree and vegetation killer.  No sign of brown needles yet after 3 months. 

Anything else I can do to hasten their death? It must be something that is not obvious. For instance I can not strip the bark all the way around. I'd like them to look dead before spring.

Thanks for the help!

[asy]

Sorry, I don't know how to kill the tree, other than the fast way (using a chainsaw) but I gotta ask...

Your mum won't let you cut the tree down unless it's dead, but she will let you kill it? Or does she not know you're aiding it's demise?

Just doesn't make sense, why would she let you kill it slowly, but not quickly?

asy :D

[Modat22]

could you drive a few copper nails into the trunk? I might be wrong but I think that would hasten the demise of the old beast. Watchout for those tree sprites though...

[slowzuki]

Sure, just decide that you like it so much and want to save it now.  For sure it will toss its cookies and keel over soon after that. :D

[Steven A.]

asy, heck NO she doesn't know what I'm doing! 
I suppose thats not good but the trees have to come out when the septic is replaced and since the trees are somewhat close to other desirable trees and her garage and her home and on a nice lawn I d like to have some time to take them out without wrecking anything else instead of a rush job when the septic tank rusts through and collapses.

[Tom]

Steven,
you have already done the most lethal thing you could do by girdling the tree.  Beneath the bark is the cambium layer.  It is what generates growth and carries nutrients to the top of the tree.  If you girdled the tree and it didn't die, then you didn't go deep enough or wide enough to stop the flow of nutrients.

There are herbicides that can be injected, but they need to be put where the tree can take them up and not deep in the center of the log.  They must also be administered in lethal solutions/strengths and growing periods.  An injection of a spot herbicide like you get from the box store for killing grass in a sidewalk crack might not have much affect.  Perseverance by continued use might cause the demise of the tree.

There are also different herbicides for different types of plants. Some affect conifers, some affect broad-leafs, and some are general or non-discriminatory.

[jkj]

If you girdled the tree and it didn't die, then you didn't go deep enough or wide enough to stop the flow of nutrients.

I found that out.  I tried girdling some Ailanthus trees so the thick canopy of leaves would die and fall off before I cut them down.  A month later, and all trees still looked healthy.  On closer inspection, I found the tree was regrowing bark over the girdling. 

I ended up just pushing those over with my tractor.  I still have 20 or so of the nasty things to get rid of - they grow like weeds and are loaded with seeds.  I'm finding 4' saplings in one hay field every year.

JKJ

[SwampDonkey]

The trees will likely die, as the live cells will be reprived of food produced from the leaves, not from lack of soil water or soil nutrients. ;)

A little physiology...

The flow of soil nutrients is up through the xylem (Greek for wood) which is behind the cambium, deeper in the tree. It's a one way street. The phloem, which is on the outside of the cambium, or the inner bark is where a downward flow and upward flow of plant produced food (sugars) from photosynthesis occurs. It feeds the live cells in the branches, trunk and roots. The cambium is undifferentiated plant cells that can produce xylem to the inside or phloem to the outside through cell division. Phloem is derived from the Greek word for bark.  The flow of soil nutrients is caused by transporation and root pressure, via the flow of water. The flow of plant organic compounds (includes sugars) in the phloem is controlled by turgor pressure (phloem sap moves from sugar sources to sugar sinks). That sap your collecting in spring from maple trees is comming up from the roots through the phloem where it has been stored before dormancy (in spring roots become a sugar source). ;D

cheers

PS, I'm really rusty on this so I had to refresh my brain cells. ;)

[jimbo]

  i would give  SALT a try in the holes you have drill thatway it would go in and not be seen worth a try anyway
                                                            jimbo

[Furby]

Sorry to break it to you but you can't simply have the septic tank and field "replaced".
They are abandoned and a new tank and field sited.
Any excavating around/in an active tank or field is considered hazardous waste and a lot of townships, cities and couties as well as some states will not allow it.

[Mike_Barcaskey]

The flow of soil nutrients is caused by transporation and root pressure, via the flow of water.

marshmule, I am assuming you mispelled transpiration.
The upward flow of water and nutrients in the xylem is aided by the "flow" or "pull" in the vessels caused by transpiration (evaporation) of water out the stomata on the leaves.
as water transpires out the leaves it "pulls" the new water and the nutrients that are dissolved in it up the xylem from the roots.

[SwampDonkey]

Yup, Mike. 

[pineywoods]

Don't know if it would work on spruce(don't have any here) , but this method will kill sweetgum rather quickly, including the roots. Drill a couple of 1/4 inch holes about 2 inches deep on oppisite sides of the trunk. Pump the holes full of ordinary old home-owner roundup. The tree will start dying at the top and continue all the way to the roots.

[SwampDonkey]

It probably will work on the spruce during the growing season before the buds harden off at summer's end.

[chet]

One of the better herbicide controls for the Spruces is Picloram. You might try looking at one of the Tordon products. But personally I think your best choice is da chainsaw.  ;)

[treecyclers]

I have used table salt to kill vegetation, as well as distilled vinegar.
The salt dries out the cells when it's taken up into the tree, and kills it from the inside out.
Vinegar burns the roots, or so I have been told, and kills that way.
The downside to both is that it takes a while for anything to grow in that area again, until the salt/vinegar leaches out sufficiently to negate the effects.
SD

[Bill]

I too use the salt and vinegar approach though I use it mostly on poison ivy. Sometimes takes a couple applications and I try to keep it just on the PI to not kill off anything else nearby.

( iffen you wanna go Biblical the ancients used to sow salt in the fields of those they vanquished to kill vegetation now and into the future )

Good Luck  . . .

[Max sawdust]

Sorry to break it to you but you can't simply have the septic tank and field "replaced".
They are abandoned and a new tank and field sited.
Any excavating around/in an active tank or field is considered hazardous waste and a lot of townships, cities and couties as well as some states will not allow it.

Thats my thinking too.  Maybe we better save those trees, cause we got to be cutting down some others for the new septic field :

Steven A, I suggest checking into what Furby said before continuing.
max

[Steven A.]

The septic regs here allow replacement at the same site.

[maplewoman]

Definatley drill a shallow hole and apply a systemic herbicide, the trick is to get the poison onto the sap before the sap dryes and stops translocating so it must be done immediately.