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Purkey Landscaping Co.
03-05-2009, 09:47 AM
I have a project in the back of a residence that has alot of clay soil. In this spot we installed a Six foot dogwood tree and it keeps dying because every time we remove it to plant another, the hole is full of water. I think it is dying because of water in hole. What to do to get water out of hole so tree can survive. Need some help about clay soil.

Perry Purkey
perry@purkeylandscaping.com

Grassmechanic
03-05-2009, 12:18 PM
You'll have to raise the rootball slightly above grade when you re-plant. Amend the clay and use it as backfill.

Kiril
03-05-2009, 12:20 PM
1) Plant a more appropriate tree that can handle the soil conditions
2) Find the source of the water problem and fix it.

MarkintheGarden
03-06-2009, 01:04 AM
It sounds like you created "hard pan" (compacted wet clay) at the bottom of the hole where you installed the dogwood. The result is no drainage and the roots get soaked, drowned and then rot.

It can be nearly impossible to dig out the hard pan, but it can be done if the soil is dry.

I would find another place to plant a tree if that is an option.

AGLA
03-06-2009, 07:09 AM
I agree with Kiril.

My guess is that the source of the water is just surface runoff that is getting to the edge of your planting hole. Then it drains in through the looser material (your planting media or backfill) and fills the hole like a bucket. The area around the planting hole needs to be raised slightly (before putting the plant in the hole) with the existing soil in order to keep surface water from getting to the hole.

Using unammended soil as a backfill is one school of thought that is increasing in popularity. That reduces how much easier it is for water to behave differently in your planting hole.

Kiril
03-06-2009, 09:57 AM
Using unammended soil as a backfill is one school of thought that is increasing in popularity. That reduces how much easier it is for water to behave differently in your planting hole.

Bingo. When you change the characteristics of the soil, you then change how it reacts to the environment. In my particular area this translates to soils drying faster than the "native" surrounding soils, which in turn causes people to dump more water on their landscape in an attempt to compensate. In heavy soils this results in the majority of the landscape getting over watered, which then leads to other problems.

MarkintheGarden
03-06-2009, 10:50 AM
I have a project in the back of a residence that has alot of clay soil. In this spot we installed a Six foot dogwood tree and it keeps dying because every time we remove it to plant another, the hole is full of water. I think it is dying because of water in hole. What to do to get water out of hole so tree can survive. Need some help about clay soil.

Perry Purkey
perry@purkeylandscaping.com

When you removed the dead trees and found that the hole was filled with water, did you notice a rotten smell?

If so, I respectfully suggest that you ignore what others have posted here and read what I posted about hard pan.

Do not plant your dogwood in the same spot again, and do not plant a dogwood above the grade.

In order to prevent this in the future, do not plant in wet soil conditions. If the soil is sticking to the shovel it is too wet to plant.

Kiril
03-06-2009, 11:10 AM
When you removed the dead trees and found that the hole was filled with water, did you notice a rotten smell?

If so, I respectfully suggest that you ignore what others have posted here and read what I posted about hard pan.

No offense dude, but would you care to explain how one would go about creating a hard pan by digging a hole? Furthermore, I fail to see the relationship between a "rotten smell" and hard pans. A more appropriate term here would be confining layer. If he is digging in heavy clay, just the simple fact he has disturbed the soil leads to a change in hydraulic conductivity. Amend that soil and it is even a larger change.

There are other possibilities as well, such as a high water table, or a natural low spot on the site which collects water.

MarkintheGarden
03-06-2009, 12:12 PM
No offense dude, but would you care to explain how one would go about creating a hard pan by digging a hole? Furthermore, I fail to see the relationship between a "rotten smell" and hard pans. A more appropriate term here would be confining layer. If he is digging in heavy clay, just the simple fact he has disturbed the soil leads to a change in hydraulic conductivity. Amend that soil and it is even a larger change.

There are other possibilities as well, such as a high water table, or a natural low spot on the site which collects water.

When you work in wet clay a layer of hard pan can occur. If you stand in the hole while or after you dig it, hard pan is more likely. When we plant a tree, it dies and we re-plant a tree in the same spot, we have an increased possibility.

I could type for an hour about hard pan, but you can read about it in many books, web pages, garden magazines, etc.

a "confining layer" is a good term, and may be a better name for it, but the term hard pan has been in use since way before our time. There is a horticultural term I learned but it escapes me.

When hard pan occurs at the bottom of a planting hole, water gets caught in the hole and does not drain. When you remove the plant it is good to see if the root was rotting or not by noticing the smell. This can help us determine the cause.

Yes, this particular case may be due to some other cause than hard pan. I wish I could just come look at the situation, but I am in the clay capital of the USA.

In my experience when I hear that someone has planted and re-planted in the same spot, I know the conditions are ripe for hardpan.

The fact that the hole was full of water when he removed a dead tree is a pretty sure sign of some problem. If he planted a new tree into the water filed hole in the clay, then that is an almost certain recipe for hard pan beneath the new tree.

MarkintheGarden
03-06-2009, 12:28 PM
There are other possibilities as well, such as a high water table, or a natural low spot on the site which collects water.[/QUOTE]

Sorry sometimes it takes more than one post for me to make my point, and that being:

Yes, there are probably other factors, but if he did not have hard pan beneath the original tree, then it is almost certain it has occurred along the way during the replanting(s).

Kiril
03-06-2009, 12:34 PM
To avoid chasing down a more suitable reference I refer you to the Wiki on hard pans.

http://en.wikipedia.org/wiki/Hardpan

Kiril
03-06-2009, 12:36 PM
Yes, this particular case may be due to some other cause than hard pan. I wish I could just come look at the situation, but I am in the clay capital of the USA.

And here I thought that my soils at 45-55% clay content was the clay capitol. :laugh:

MarkintheGarden
03-06-2009, 04:32 PM
Thanks for the link, I love Wiki, and often forget that it is there for the quick reference.

I am not sure what the clay content is here, but it is high, the area is a basin.
I have learned the hard way what will grow in clay, some plants love it but they are mostly weeds.

White Gardens
03-06-2009, 05:47 PM
Hardpans do occur from digging, even hand digging.

When I've run into this situation, it's usually because the builders of the home used the yard as a parking lot.

What I've done with trees in this situation, is to dig the hole, and use a one-man auger to drill a drain hole in the bottom as deep as I can. This creates a hole under the tree to allow the water to drain past the hardpan. I also backfill the hole with a sand/dirt/rock mixture to aid in drainage.

Haven't lost a tree yet using this method.

Think Green
03-06-2009, 07:21 PM
Perry,
Digging in clayic soil is perilous and backbreaking. Did you dig the hole 2 times the circumference of the root ball.? What backfill did you amend the hole with?
We do as stated above and drill out a hole 12-14 inches deep and 3 inches in circumference to allow for water to disperse downward. Fill the hole with rocks, sand,etc. If the total area of the bed is hard clay, then you will pretty much have a hard time of keeping trees to live untill the water is reduced or draining tiles or pipes have been placed. If all else fails, raise the root ball above the water line. If the hole is full of water, then there is another serious problem at hand. Don't plant anything else there until you figure out the reason. Tell the customer of the problems and advise them to plant a variety more suited for water conditions.

Smallaxe
03-07-2009, 08:34 AM
White gardens and Think green have the most logical idea. Provide drainage.

Unless that is the water table. :) In that case your only option is to raise sufficiently and build and environment that does not allow for root rot.

White Gardens
03-07-2009, 10:04 AM
White gardens and Think green have the most logical idea. Provide drainage.

Unless that is the water table. :) In that case your only option is to raise sufficiently and build and environment that does not allow for root rot.


I got the idea from the farm. Before installing drain tiles became affordable, farmers in our area would go out in a field that was holding water and use a post-hole digger to drill holes in the low spots, and it actually worked really well for about 3-5 years before you would have to do it again, and that is just digging the hole and filling it in with the same material.

I agree about the water table though, if it's high then your SOL without doing a major drainage project. Luckily I haven't run into that here, and it's all a matter of cussing out the builders of the home for building a 500,000 dollar house, and doing major damage to the lawn.

I think my next project will be when I get my mini-skid this year is to buy a vibratory plow and weld "wings" on it. I'm hoping to go into some really bad yards and use it like a soil "ripper" that penetrates the lawn 6-10 inches down and lifts the soil to help break compaction. It lifts the soil without creating a hardpan, and also leaves the surface sod undisturbed so you could come in and smooth it out when your done and have the grass come back fairly fast. Another idea I got from the farm.

138861

Smallaxe
03-08-2009, 05:42 AM
Could be true. I believe that 'clay' anywhere is a hardpan. Drawing the line in the tilled region vs the untilled region and calling everything below that line a "Hardpan", is all well and good.

Saying that a vibrating moldboard will eliminate the distinction of a hardpan is only symantics in my view.

Good idea though.! Keep moving the "Living Soil" downwards.!! :)

AGLA
03-08-2009, 09:47 AM
There are different types of clay. Clay, by definition, is a partical size. There are different types of clay structures that behave differently.

Whether it is "hardpan" or not, water is absorbed slowly by it because of the small sized pore space between the particles. Water is also held more tightly for the same reason.

Since this problem occurs when it rains, the most obvious thing to look for is that surface runoff is moving on or near the surface of the soil because it is not getting quickly absorbed. As it does that and comes across a surface that lets it in, it will enter it. In the case in this thread, it is a backfilled hole with either a looser material or soil ammended with a more porous soil that lets the water in. The water enters and has no place to go because the walls and bootom of the holes are of tight clay. The result is that water keeps entering and not exiting untill the hole is completely saturated. It is like having a bucket full of soil with water continually added to it until it can't take any more.

This can be reduced by limiting the ability of surface water getting to the hole. Planting the tree higher out of he ground usually means that the backfill will be mounded slightly around the hole. Surface water does not run up hill even if the soil is looser, so it tends to flow around the area of the hole and not into the hole. Many people assume that lifting the plant takes it out of the water filled bottom of the hole when it is more likely that it diverts the water instead.

Making a bigger hole in tight soil can work against you if surface water is the problem because it opens a greater area for surface water to enter the hole.

The example of using a post hole digger in a farm field is most likely to punch holes through the clay layer to a more porous layer of soil beneath. Short of that, it can create a bigger surface area of the undisturbed clay so it can absorb water faster as well as being able to store some volume of water in the fluffed up pores in the holes themselves.
Water table is a totally different story.

Smallaxe
03-08-2009, 02:39 PM
There are different types of clay. Clay, by definition, is a partical size. There are different types of clay structures that behave differently.

Whether it is "hardpan" or not, water is absorbed slowly by it because of the small sized pore space between the particles. Water is also held more tightly for the same reason.

Since this problem occurs when it rains, the most obvious thing to look for is that surface runoff is moving on or near the surface of the soil because it is not getting quickly absorbed. As it does that and comes across a surface that lets it in, it will enter it. In the case in this thread, it is a backfilled hole with either a looser material or soil ammended with a more porous soil that lets the water in. The water enters and has no place to go because the walls and bootom of the holes are of tight clay. The result is that water keeps entering and not exiting untill the hole is completely saturated. It is like having a bucket full of soil with water continually added to it until it can't take any more.

This can be reduced by limiting the ability of surface water getting to the hole. Planting the tree higher out of he ground usually means that the backfill will be mounded slightly around the hole. Surface water does not run up hill even if the soil is looser, so it tends to flow around the area of the hole and not into the hole. Many people assume that lifting the plant takes it out of the water filled bottom of the hole when it is more likely that it diverts the water instead.

Making a bigger hole in tight soil can work against you if surface water is the problem because it opens a greater area for surface water to enter the hole.

The example of using a post hole digger in a farm field is most likely to punch holes through the clay layer to a more porous layer of soil beneath. Short of that, it can create a bigger surface area of the undisturbed clay so it can absorb water faster as well as being able to store some volume of water in the fluffed up pores in the holes themselves.
Water table is a totally different story.

Yes, definately dig down to drainage soils. If that don't happen - then raising the plant and channelling surface water away will be useful, as an additional tool.
Just be sure to have the correct balance, because you want the root ball to remain moist and yet not standing in sitting water.

White Gardens
03-08-2009, 04:00 PM
Could be true. I believe that 'clay' anywhere is a hardpan. Drawing the line in the tilled region vs the untilled region and calling everything below that line a "Hardpan", is all well and good.

Saying that a vibrating moldboard will eliminate the distinction of a hardpan is only symantics in my view.

Good idea though.! Keep moving the "Living Soil" downwards.!! :)

You'll never truly get rid of the hardpan, but the idea behind lifting the soil would be to help promote soil on a newly established lawn that is consisting of mostly clay. The upward lift of a sub-soiler, or ripper, would help create voids and better soil to move in to reduce compaction. I've seen to many new lawns that had the whole yard used as a parking lot, a skid-steer and Harley rake to grade, and sod slapped down when done. So the compaction has made such a bad environment for sod and natural processes to reduce compaction.

Basically you would achieve the upward lift that 10 years of frost/freeze cycles would produce.

Smallaxe
03-08-2009, 04:25 PM
Agreed.
That is why it doesn't make sense to me - to aerate in the spring.
And I hate the idea of levelling an area for lawn with a skidster.

It may the the quickest and cheapest for some people , but it is certainly not the most cost effective over 5 years.

StoneFaced
03-08-2009, 04:36 PM
A lot of solid advise on here...Considering all the possible case scenarios, any chance of posting a wide angle pic of the area in question?

Just a simple thing to remember is that water will always take the path of least resistance, so if your planting on the down grade, it might not help sometimes to channel the water, if the bed itself is catching and holding...lots of possibilities. Irrigation systems are great, but often are a contributing cause to these types of problems as well, and can be a challenge.
Not sure if it's been asked or stated...Does the yard have an irrigation system?

wurkn with amish
03-08-2009, 06:12 PM
Originally Posted by AGLA
Using unammended soil as a backfill is one school of thought that is increasing in popularity. That reduces how much easier it is for water to behave differently in your planting hole.

Farmers should have been teachers at the Tech schools. Cause this is common sense to them.
There's good advice given on here..... but there is also a tree suited for every environment, make sure you choose the right one. Just because the home owner wants a dogwood doesn't mean one will grow there.

shovelracer
03-08-2009, 07:55 PM
Most of the advice is good. It is very true that any plant must be in the right environment. This is usually your best approach. However, sometimes you need to change the environment because that is what the project calls for.

Years ago I got called on a job, homeowner had a row of pear trees that were rotted and they were the second ones they planted. We looked over many different options from drainage to other species. Basically their answer was that they needed to do whatever possible to kept the species in the location. In the end we decided to amend the soils in that area of the property as it was a problem of subsurface drainage caused from the builder. We basically excavated 6-10 yds of material from each hole, amended it with more organics and drainage gravel and replanted new ones. They are fine, big, and healthy and this was like 5 years ago. The others lasted less than a year each. Not ideal for the cost and work involved, but it was necessary to match the others in the area.

Smallaxe
03-08-2009, 08:09 PM
Originally Posted by AGLA
Using unammended soil as a backfill is one school of thought that is increasing in popularity. That reduces how much easier it is for water to behave differently in your planting hole.

Farmers should have been teachers at the Tech schools. Cause this is common sense to them.
There's good advice given on here..... but there is also a tree suited for every environment, make sure you choose the right one. Just because the home owner wants a dogwood doesn't mean one will grow there.

I like the idea of native plants a little as the next guy, but accepting the challenge of giving the client what he wants, is good too.
Pushing the envelope always teaches you you something as well. :)

White Gardens
03-08-2009, 09:42 PM
Agreed.
That is why it doesn't make sense to me - to aerate in the spring.



Oh, tell me about. About 10% of lawns I've aerated truly actually needed an aeration as the natural processes in the lawns were more than sufficient.

1% of lawns I've aerated actually needed a spring aeration.

In my classes I was told that the only reason aerations and de-thaching became popular, was when grub control products, and insecticides in the late 70's and early 80's were killing off the earth worms.

Kiril
03-08-2009, 09:57 PM
You'll never truly get rid of the hardpan

Assuming one even exists.

White Gardens
03-08-2009, 10:05 PM
Assuming one even exists.


Yes, assuming, you can only go by the history of the lawn, or use a compaction meter to find out if there is a hard-pan present. But even then you might just hit a hard spot when testing while the rest of the lawn is fine.

weasel
03-09-2009, 01:17 AM
Gypsum loosens clay with little effort. Just apply and rake a little.

Kiril
03-09-2009, 01:33 AM
Gypsum loosens clay with little effort. Just apply and rake a little.

Not necessarily.