Digging out the First Elm Tree Stump, Part 2

 Once we had the stump out of the ground, we were able to dig down below where it had been.  We found a layer of rock -- limestone rocks mixed with dirt.  The limestone was fairly flattish rocks for about 4 to 6 inches, and then we hit bedrock. We dug out the entire hole that we had needed to get the stump out.

The question then is what this layer of bedrock consists of, and how deep does it go.  An hour of jack hammering showed the limestone bedrock to be hard and solid at least 6 to 9 inches down.  It does not break easily, but with repeated work can be reduced to dust and rubble -- taking a lot of time for very little result.

As it is we have a pit that is 24 to 30 inches deep, 6 feet across, which seems as good as we can do without a major effort.

 At this point, we can fill the pit back in.  We want it to be good soil that will be easy to work with, and have plenty of composed material for whatever is planted.  And we can easily bury anything we need to get rid of.  So we rake up all the seed droppings from out Chinese Pistache tree and put them at the bottom of the pit.

That was 4 wheelbarrows full of droppings.  Then we start shovelling dirt from the pile into the pit.  After about a third of the pile is in the pit, we spread leaves over the dirt.

After a couple more days of shoveling dirt from the pile into the pit, mixing in leaves at intervals, we have the pile gone, and the pit filled in.

Actually, the pit is more than filled in.  The dirt leaves a mound about 9 inches high.  Since all of the dirt that used to be in the pile came from the pit, plus we pulled out the stump and a lot of rock, it seems that over time, the dirt will settle and probably be lower than the surrounding ground. 

Protecting the Pecan Tree from Squirrels

 The two pecan trees are doing very well.  The first one was planted in 2015; the second one in 2017.   Both are now producing nuts.

The first one is very close to other trees, so there is no practical way to keep the squirrels off -- they can jump from other trees or from the fence.  And as a result, they have consistently stripped the tree of any nuts before they are ready for us to pick them.

The second one, on the other hand, is still fairly small and distant from other trees and the fence.

To keep the squirrels off of it, we tried first a collar (like a cone for a dog or cat) on the trunk, but that didn't stop them.  So now we have put a metal stove pipe over the trunk. 

We bought a 5 foot (length) by 4 inch (diameter) and then cut it down to 46 inches in length, to fit between the lowest branch and the trunk flare at the bottom.  Its slippery surface should prevent squirrels from climbing up the trunk.

If this works, then we will have pecans!

Digging out the First Elm Tree Stump

We lost two Elm trees and had them cut down in 2021.   This left us with two stumps in the west side yard.

We did not have time to work on those in 2021, so we buried them under dirt leftover from part of the front yard digging.

So to dig these stumps out, the first thing we need to do is move the dirt off it, to expose the stump.

Once the stump is exposed, we can start digging down around it.  The plan is to encircle the stump with a trench, cutting off roots as we go around and down until the stump is disconnected and can be removed.

We start digging down on one side.

We can then extend that around the stump.

It would be easier to dig, if we knew where the roots were and how big they were.  The air spading that we did in the front yard to find the roots for Fuzzy would be really useful here.  But that was very expensive.  As an alternative, we have the high pressure washer.  We used that to tunnel under the front sidewalk.  So we tried that around the stump.

That seemed to work reasonably well, although it then takes days for the water to soak into the surrounding dirt and dry up.  So it's not a fast process.

Once the soil mostly dries out, we can go back to digging out around the stump.

 The process is pretty simple.  Try to remove the dirt.  Find a root.  Cut thru the root, both close to the stump and at the edge of the pit we are digging.  Smaller roots, we can use a pair of branch clippers -- a bypass lopper.  Bigger roots, we use our grubbing hoe-axe combo.

After a couple of days, with rain coming, we try the high pressure water spray again, to clear the dirt off the last set of roots.

Once this (and the rain) dry, we can cut thru as many of the roots as we can see, dig down to get more, until we have the entire stump encircled with the trench, going down to rock, cutting all the roots off.

We left a couple of big roots sticking out from the stump, so that we could get under them and use them to try to lift the stump up.  For that we use a bottle jack that we purchased for this purpose.

We position the jack on a rock under a big root and lift it up as high as we go.  Then we stack rocks under the root and lower the jack down.

As we repeat this around the stump, it is clear that the stump is loose from the ground.  The problem now is: how do we get it out of the pit and dispose of it?

The stump, with all it's attached roots, and the dirt packed in on the bottom, weighs a lot.  I can barely move it; I certainly can't lift it.  So as with large rocks that we uncover, we will have to break it down into smaller pieces.

The approach we take to that is to try to split pieces of it off using a sledge hammer and a set of wedges.  Select a piece that looks sort of separate, and insert a wedge in a crack.  Hammer the wedge into the crack, making the crack grow larger.  

 

Use other wedges to continue to grow the crack, until the piece separates and can be removed.  

With luck, this creates a set of additional cracks, which we can then go back and use the wedges and the sledge hammer to further crack apart the stump.

Sometimes the wedges can only go so far and separating off a section takes a wider crack than the wedges can make.  A wedge is only about 2 inches, and even putting two wedges together only gets to about 4 inches.  You can move the wedges down the crack to widen it at the middle, instead of just at the top, but still there are limits.

In those cases I went for a jack.  The bottle jack that helped lift the stump up and separate it from the earth is a vertical structure, so it needs 8 to 10 inches, and then only adds another 6 inches.  So I use a scissor jack that is normally used to change a tire on a car.

A scissor jack starts out fairly flat -- mine starts at 4 inches -- and can be cranked to over a foot. You do have to be careful in case thing slip, and there are limits on how much pressure you can apply without damaging the jack.

But if by keeping at it, wedging, jacking, sticking large rocks in gaps to keep them open, I was able to continue to pare down the remaining intact part of the stump.

Until eventually the part of the stump that was left was small enough 

that I could wrangle it out of the pit, leaving an empty hole

and a selection of large pieces of what used to be the stump.

Zone 11 Irrigation Rebuild

Having completed the excavation of the front yard between the drive way and the sidewalk, we need to redefine the irrigation system for this area, Zone 11.  We have water coming from under the sidewalk, and two heads around Fuzzy, the oak tree, but the lower area, from the retaining wall around Fuzzy to the bed in front of the library, has nothing left from the old Zone 11.  The bed in front of the library has been moved to be part of Zone 9.

Tracing part of the original irrigation blueprints, we can lay out how we want to do Zone 11.

We decide to put 4 new heads into the lower part of the yard -- one in each corner between the sidewalk, retaining wall, drive way, and front bed.  We have a 3/4 inch pipe coming from under the retaining wall.  We will attach the new pipes and heads to that, putting in one new head by the retaining wall and the sidewalk, extending down to the next head by the sidewalk and the front bed.  Then across the yard to the corner by the garage, and finally back up to the retaining wall for the 4th head.

Part of the motivation for this is to minimize the digging in the unexcavated area just below the retaining wall where we did not want to disturb Fuzzy's roots.

First we have to dig up the remnants of the old irrigation pipe.

We cut off and discard the old pipe, but attach a new pipe with a new head.

As we are digging to lay the basic supply lines, we realize there is little value in going to far towards the house. We stop the line going down from the retaining wall and run it to the driveway.

These supply lines are all 3/4 inch PVC.  We run smaller 1/2 inch lines diagonally from the corners to the new heads, like the one by the bed and the sidewalk.

And to the new head by the garage.

Then we run the line back up to the retaining wall.

And finish with the last new head.

Once we test for leaks, and flush all the lines, we can put the dirt back to hide all the pipes and connections.

For the heads, we choose the rotary Rain Bird 8SAPROPR Pressure Regulating (PRS) High-Efficiency Pro Rotary Sprinkler.  Installing the four new heads is routine, but we also need to replace the other two heads, in the upper section above the retaining wall.

The first one, next to the retaining wall and the driveway, is easy enough; the soil around it was added when we did the retaining wall in October 2021.  But the one at the corner of the street and the driveway is more difficult; it is still one of the original heads from installing the irrigation system in 1988 (?).  Trying to dig it out broke all the old PVC pipes and connections.

But that allows us to replace all that pipe as well as the head and put in better dirt.

This gives us 6 new rotary heads to finish off Zone 11.  Flush the lines, adjust the heads, and call it a day.

Extending Zone 9 to another bed

 With the small front yard area between the sidewalk and the driveway dug up, and put back, we can turn to the irrigation system.  We have 3 areas to consider -- the top around the Oak tree (Fuzzy), the middle, and the bed by the garage and the front porch.  The bed is likely to be different from the other two areas, and we have another bed on the other side of the sidewalk, next to the house, so it seems natural to add the front bed to the already existing Zone 9, and then use Zone 11 for the other two areas.

The main difficulty is that the sidewalk is between the two beds.  To extend Zone 9, we will need to tunnel under the sidewalk to run a pipe to connect the two sections.

First we did down on the "new" side of the sidewalk, to expose the pipes that we want to connect to.

The pipe going towards the street is where the water used to come in, but now is just disconnected.  We remove it.

On the other side of the sidewalk, we have a sprinkler head (the end of Zone 9).

We dig down to find the actual pipes. We have to be careful here not to disturb the plants.

Getting under the sidewalk seems to be the main problem.  Our model of the sidewalk is about 4 to 6 inches of concrete, then some dirt they put down as a base for the concrete, and eventually, construction debris or the native mix of rock and dark clay soil.  But it appears we have only dirt, and digging thru that, we hit concrete.

Our view of the sidewalk is obscured by the stone edging of the bed.  If we remove it, we can see the actual sidewalk structure itself.  So we do.

With the stone edging gone, we can see the sidewalk structure clearly.

Our basic model is correct, although it may be 8 to 10 inches of concrete.  Then a layer of light brown soil (sandy loam?) used as a base -- about 6 to 8 inches.  Then probably construction debris, but whatever, it's rocky.

So our best chance of getting thru is in the sandy loam.  But how to do that?  After much investigation of masonry core bits, earth augers, and such, we realized that the sandy loam is very soft and decided to just use a high pressure water stream.  We used our pressure washer and was able to get thru more than 2 feet of the dirt.  Then putting our six-foot pry bar in the hole and using a sledge hammer, we were able to break thru to the other side.

The pry bar was useful to dislodge the large rocks that had been buried in the sandy loam, and to enlarge the hole so that we could slide a 3-inch PVC pipe thru it.

Then we could run a 1/2-inch PVC pipe thru the 3-inch pipe and connect it to both the old Zone 9 line

and connect it to the 3 sprinkler heads in the bed next to the garage.

We had to cap off the end of the new section of pipe, in the bed close to the garage.

And, it turns out, there was a leak in Zone 19 that I had to fix too. Over by the gas meter, the line that ran from the heads near the house across, under the River of Rocks, to the wall at the neighbor's property line.  That line had come loose -- it looked as if when the new Zone 9 layout was done in August 2019 this line was near cemented in place; the pipes were just fitted together.

Once that leak was fixed, we could test Zone 9 and it worked as expected, allowing us to shovel the dirt back into the holes on both sides of the sidewalk.

Zone 9 now has about 19 heads on it, which seems like a lot.