Vertical Mulching

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I don't understand your statement that the air tool compresses the walls of the hole. If anything, in a clay soil it tends to fracture and lift the soil.

Since neither one of us nor anyone posesses xray vision this is mostly conjecture but...if you make a space by vert mulching with air gun down into clay soil....where does the displaced soil go that was in the space now occupied by the air/airpressure?

It must compact the surrounding soil (not just the wall of the opened space) just as though you ran a steam roller over the top of the soil and displaced into a rut downward and compacted the soil below.

Ofcourse there is some lifting the longer you pump the air in there but still....

I think most of this air spade stuff is just a gimmick except exposing the root crown which is very useful for a variety of reasons.
 
It makes sence to me the air spade is going to be forcing pressure down on the soil where as the auger is going to pull soil out of the hole and displace it. As far as exposing the root flare wouldn't a high pressure watering hose do the same as an air spade?
 
That's not what the airspade does. It blast the soil out of the hole.

You couldn't cause soil compaction with an airspade if you tried.


love
nick
 
That's not what the airspade does. It blast the soil out of the hole.

You couldn't cause soil compaction with an airspade if you tried.


love
nick
X2! The Air Knife lifts large areas of soil, sometimes 2'+ from the nozzle

Augers downside is drilling through roots. Slight problem there...:bang:
 
I disagree with you and Nick and have seen one work many times. Soil is excavated in a root crown excavation. When aeriating some soil comes out but most stays in and MUST compact in the perimeter of the space created by the forced air. Dessication of fibrous roots has to occur as well.
 
I disagree with you and Nick and have seen one work many times. Soil is excavated in a root crown excavation. When aeriating some soil comes out but most stays in and MUST compact in the perimeter of the space created by the forced air. Dessication of fibrous roots has to occur as well.

Not my experience with air spade. I guess results vary.
 
You could only compact soil with an airspeed if you used the wand end the beat the mud tight ! :msp_w00t:
:laugh:

The auger on the other hand glazes clay soil as it spins. no xray vision needed--poke your finger down there and feel the smooth.
 
I think the degree of glazing correlates to the auger speed, and a slower speed will cause less glazing problems. Soil moisture content is another variable re. glazing.
Air injection will follow the path of least resistance, ie. mostly towards the soil surface, which is also why blasting holes are capped with mud or something similar, in order to direct the explosion downwards and outwards. Instead of upwards.
Automatic weapons use recoil / gas blowback to cycle too, don't they? All conjecture on my part, as Canadian laws kinda restrict possession of explosives and arsenals in private hands. :msp_sneaky: But some soil compaction with an airspade seems a reasonable possibility.
 
Mebbe it ain't a great notion to verti mulch Mrs Smith's compacted Magnolia right after a heavy rainfall using a high speed drill?
 
I've never seen soil being compacted on the side wall of a hole when using an air spade, but we have coarser soils. Most soil gets either blown out of the hole or into the area that was previously excavated.
 
There can be some compaction with air tools, but my experience is that it is a very thin layer on harder soils. Mechanical compression is much worse with a drill, shovel or anything one can dig with. Any procedure will have some drawbacks, I've done mechanical, pneumatic and hydro excavation around trees, my preferred is pneumatic.

One good thing about auger amendments is that one can take a low cost treatment to prove a point to a client reluctant to invest in extant specimens, especially if they have "always looked like that. " When they see that the sulfuric acid "rootbeer float" greens an oak up within a few weeks we can often get in and do some work that will affect the tree for a much longer period.
 
Hello everyone, I'm new to the vertical mulching thing and looking for some tips. I would like to add VM to my services as an alternative to fertilizing for rejuvenating old and sick trees. I would be using an 6" auger bit on a stihl drill. I would like to hear about other methods for applying and especially what kind of cocktails you guys use to backfill the holes. The local landscape supplier has garden compost for sale which is a mixture of peat moss, hay, cocoa bean hulls, cotton seed meal, and poultry litter. Also anyone been experimenting with mycorrhizae as part of the ingredients when VM? Thanks!
Vertical mulching is by far the best thing you can do to any desirable tree in any soil type and should be considered as vital as pruning and watering. That said, know your soils and soil pH. Six inches is too big a diameter, stick to 2-3 inch holes. Keep the six inch bit for areas that don't drain well and fill the hole with pea gravel, this is Way easier than a French drain and a couple holes like this will really drain a spot that stays wet too long provided you get down to the naturally porous subsoil.
For 2-3 inch holes 12-24 inches deep, start about six feet away from the crown of the tree and make holes 2-3 feet apart in concentric circles out to or just past the drip line. For clay soils fill holes with fine screened compost mixed 50/50 with sand, some gypsum, and a mycorrhizal inoculant. For Sandy soils, use straight compost and mycorrhiza. For really dense poorly draining soils, use compost and pea gravel with gypsum and mycorrhiza. Use a broom handle or dowel to Tamp the mix into the hole as you fill, air pockets will kill roots. You can add fertilizer, but go with a slow release or organic fertilizer to avoid root burn.
Depending on pH, add some acidifying fertilizer or lime to the mix. Vertical mulching is great for trees but will also do wonders for a yard or ball field. For a sports field, you really want to make sure to Tamp down the fill material firmly all the way to the surface and leave a little mound on top so there are no divots.
For all vertical mulching, water in everything thoroughly.
Vertical mulching, especially with mycorrhizal inoculants and compost (real fine screened compost, No wood chunks) will add organic materials to the soil, improve drainage as well as water retention! This will reduce water bills, add to the effectiveness of fertilization, decrease the formation of surface roots on younger trees, add vitality and vigor to any tree young or mature, aerate the soil, encourage deeper root production of trees and turf making them more drought resistant, add beneficial fungi, microbes and bacteria to the soil.
Stay Far away from water mains, gas lines, sewer drains, and irrigation lines as you will make a mess and kill your profit margin.
You have to sell this service, people don't know about it, educate them.
Over time the soil will increase in porosity as the mycorrhiza grow out from the holes and the organic materials and gypsum condition the soil.
Always upsell by suggesting larger mulch rings around desirable trees, as I rarely see mulch rings the size recommend, with a nice layer of native, well composted hardwood mulch on top, you shouldn't have to water more than twice a week even in a Texas summer with little rain.
 
Calculate volume for a proposed auger hole.

Now multiply that by your number of holes in your grid or concentric pattern.

Compare that small volume to that created by trenching or decompacting with an air gun. It's not even close.

Hell, just making a huge new mulch bed with wood chips shows remarkable soil improvements from structural, chemical, to biological aspects in a surprising amount of time.

Vertical mulching/core aerating should be reserved for the circumstances of dealing with a relatively thin and shallow layer of hardpan imo.
 
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