Soil Properties

lenphillips · 1st January 2008, 05:04 PM

Online Seminars has an article called Soil Properties. It will be available for discussion at the website for January and February.
on-line-seminars.com - Soil Properties

I know we are supposed to run a soil test before planting a tree, but how many of us really do?

azrael · 2nd January 2008, 06:24 PM

Quote:

Tree Soil Volume
Ideally, tree roots should be able to grow at least to the drip line or crown edge of the tree at maturity. A soil volume of 2 to 3 cubic feet per 1 square foot of crown spread is recommended. Calculate crown projection by taking the mature crown spread of the tree, squaring it, and multiplying by .7854. For every square foot of "crown projection," the site should have 2 cubic feet of soil available for rooting.

For example, a tree that matures at a spread of 30' will have a crown projection of (30) ? x .7854 = 707 square feet and will thus require 707 x 2 = 1,414 cubic feet of usable soil volume for root growth. In a good soil, expect roots to penetrate three feet. Use this standard depth as one of the three dimensions of a volume of soil. Back to the example, divide 1,414 by 3; this equals 471 square feet. The square root of 471 is approximately 22. This means a soil volume with dimensions of 22' x 22' x 3' is needed to ensure adequate below ground space for the tree in this example.

This simple formula is ideal in the Midwest and Western parts of the US and Canada. However, it is an overestimate for trees growing in the Northeast US and the Pacific Northwest where there is more rainfall. It applies to all trees except those adapted to growing in very wet or very dry locations. Incidentally, when planting a columnar tree, use the crown measurement of a non-columnar variety of the same genus being considered.

The mathematical formula for the Area of a Circle gives the same result.
Root-areea = A = Pi x r2 (where Pi is constant at 3.141 and r is the radius of the crown....which is squared in the calculation).
No metric conversions required....if you measure in mtrs then it comes out m2, if you measure in ft, it's sq. ft.
For soil volume, multiply Area by the depth parameter....and that gives the volume of soil required for the optimal and sustainable growth of the tree. (The article suggests depth of 2-3ft...thats only 1m)...correct me if I'm wrong..... but I think that a bit on the too shallow side (maybe more like 2-2.5metres).

How do we convince planning authorities that these spatial demands are critical....and that, for example, the 6m wide deep-soil zone for development site is no-where near adequate for supporting long-term growth of healthy trees....at best this nominally sized area is only good for tall-shrubs, the smallest of 'trees'....or.... (you'll like this Ekka) ...a couple of palms.

The seminar material...again...is a good overview...but with a bigger underlying problem. I'd like to see one single Landscape Architect who assess a site to this degree.....some never set foot on a site...and I know this for FACT.... And yet it is they who nominate what is instated in the landscaping of the site.
If you are Arborist Consulting...and based on your own site assessment, you can always include a list recommended plantings (or replacement plantings). I have found, more often than not, that Council will adopt your suggestions OVER the L.Architects.

Ekka · 2nd January 2008, 08:56 PM

The landscape architect I converse with said when they did their degree they only did a short bit on tree ID, 20 species, piss easy.

Most of their selection of trees etc comes from nursery talk, they dont deal with the back end of their work like we do in 10 year+ time.

Just today I quoted a removal of all palms around a 3 year old pool, they planted above the pipes, now already broken pipes. Space between pool and fence where pipe and palm are is under 1m. Other side of fence is lower with small retaining wall. Nothing big and like only $400 to cut the lot down but there you go, only 3 years later problems.

I've seen nursery tagged trees showing only around 50% the size of what the tree is really capable of, regions are different too, how a tree grows here is different to Melbourne etc. So where they're tagged etc varies, should be tagged by region.

Qld has been shipping cocos palms by truck loads to Adelaide and Melbourne for years ... soon they'll be sorry I'm telling ya.

mdvaden · 2nd January 2008, 09:29 PM

Azrael quoted a section with this part here...

Quote:

This simple formula is ideal in the Midwest and Western parts of the US and Canada. However, it is an overestimate for trees growing in the Northeast US and the Pacific Northwest where there is more rainfall. It applies to all trees except those adapted to growing in very wet or very dry locations. Incidentally, when planting a columnar tree, use the crown measurement of a non-columnar variety of the same genus being considered.

I'm not sure why it would be an overestimate for the west US in some places.

Like in Portland, Oregon, there is hardly any rain at all from the last week of June until about the end of September. It's not extreme heat, but Portland has very dry summers regardless of the the drastic change in autumn and winter.

And I think that soil volume is very important in summer. Also, soils can loosen in winter when rain and wind allow some trees to start rocking their root systems. And this may relate to soil volume and the extent of root development.

azrael · 3rd January 2008, 01:55 AM

Quote:

Originally Posted by Ekka

...Most of their selection of trees etc comes from nursery talk, they dont deal with the back end of their work like we do in 10 year+ time....

Just today I quoted a removal of all palms around a 3 year old pool, they planted above the pipes, now already broken pipes. Space between pool and fence where pipe and palm are is under 1m. Other side of fence is lower with small retaining wall. Nothing big and like only $400 to cut the lot down but there you go, only 3 years later problems.

I've seen nursery tagged trees showing only around 50% the size of what the tree is really capable of, regions are different too, how a tree grows here is different to Melbourne etc. So where they're tagged etc varies, should be tagged by region.

Qld has been shipping cocos palms by truck loads to Adelaide and Melbourne for years ... soon they'll be sorry I'm telling ya.

Exactly what I'm saying...LA's use "plant lists" and you see the same inclusions site after site.....after site. ALL sites get at least one Sapium sebiferum at the front....(clones).

Sometimes...if youre lucky...you'll get a chance to comment on the Landscape Concept Plans relating to the Arborist Report.
I've seen cases of totally inappropriate plantings for the available space and the characteristics if the species proposed. Mel.quinquenervia is a classic example... They need a lot more space than the kerb-side area can provide.
I trot out these photos for them to look at....and suggest Tristianopsis laurina (Water Gum) instead.

You'd would be surprised how some envisage planting out the under-canopy area of retained trees...the planting activity alone is enough disturbance to eventually kill the tree....(think 300mm pots size at 500 spacings and thats what I mean). Just spots on the plan .... but in reality....big impact on shallow roots, not to mention theft of nutrient and available moisture.

PS People who sell Cocos Palms for transplanting should be

TrevMcRev · 3rd January 2008, 02:55 AM

Quote:

Originally Posted by Ekka

Qld has been shipping cocos palms by truck loads to Adelaide and Melbourne for years ... soon they'll be sorry I'm telling ya.

You want to buy em back ekka???

I got a deal for ya......

TrevMcRev · 3rd January 2008, 02:57 AM

Quote:

Originally Posted by azrael

...and suggest Tristianopsis laurina (Water Gum) instead.

Using them down here a bit too. Good lil tree.

Sean Freeman · 3rd January 2008, 03:03 AM

Len you're right more often than not the soil test is insufficient if completed at all. One problem is for the comprehensive tests I like to get done the client get stung $500 and thats without any % on top! Yes I know work it into the overall price etc... but still $500 is way too expensive some of these soil labs esp the soil food web labs are making an absolute killing.

Eric once in a while you will come across a really good landscape architect or firm, they are really worth connecting with, as Arborists we can give them a great deal of help and they can also assist us to get better outcomes in the long term, sadly it really is only once in a while!

1st January 2008, 05:04 PM	#1 (permalink)
lenphillips Gettin' motoring Join Date: Nov 2007 Location: Massachusetts Posts: 43	Soil Properties Online Seminars has an article called Soil Properties. It will be available for discussion at the website for January and February. on-line-seminars.com - Soil Properties I know we are supposed to run a soil test before planting a tree, but how many of us really do? __________________ Len Phillips Administrator Online Seminars for Municipal Arborists

2nd January 2008, 08:56 PM	#3 (permalink)
Ekka Eric Frei Administrator - Brisbane L5 (Dip) Hort Cert III Arb + some Join Date: Jan 2007 Location: Brisbane Posts: 5,673	Re: Soil Properties The landscape architect I converse with said when they did their degree they only did a short bit on tree ID, 20 species, piss easy. Most of their selection of trees etc comes from nursery talk, they dont deal with the back end of their work like we do in 10 year+ time. Just today I quoted a removal of all palms around a 3 year old pool, they planted above the pipes, now already broken pipes. Space between pool and fence where pipe and palm are is under 1m. Other side of fence is lower with small retaining wall. Nothing big and like only $400 to cut the lot down but there you go, only 3 years later problems. I've seen nursery tagged trees showing only around 50% the size of what the tree is really capable of, regions are different too, how a tree grows here is different to Melbourne etc. So where they're tagged etc varies, should be tagged by region. Qld has been shipping cocos palms by truck loads to Adelaide and Melbourne for years ... soon they'll be sorry I'm telling ya. __________________ Remember to use the "search" function, if you have answers/questions post them so everyone can benefit. Free Tree and Green Industry Link Directory Qualified Brisbane Tree Lopping Brisbane Tree Care, Consultations and Arborist Reports Forum Sponsors

3rd January 2008, 03:03 AM	#8 (permalink)
Sean Freeman PDF King & Arborist Extrodinaire Join Date: Feb 2007 Location: Townsville Nth Queensland & Gold Coast Sth Queensland Posts: 1,521	Re: Soil Properties Len you're right more often than not the soil test is insufficient if completed at all. One problem is for the comprehensive tests I like to get done the client get stung $500 and thats without any % on top! Yes I know work it into the overall price etc... but still $500 is way too expensive some of these soil labs esp the soil food web labs are making an absolute killing. Eric once in a while you will come across a really good landscape architect or firm, they are really worth connecting with, as Arborists we can give them a great deal of help and they can also assist us to get better outcomes in the long term, sadly it really is only once in a while! __________________ Sean Trees are poems that earth writes upon the sky, We fell them down and turn them into paper, That we may record our emptiness. - Kahlil Gibran

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