Stiff Diagrams  
  

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TOPIC: Stiff Diagrams
http://groups.google.com/group/entstrees/browse_thread/thread/fc861c611df2697e?hl=en
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== 1 of 1 ==
Date: Fri, Mar 7 2008 1:28 pm
From: "Edward Frank"


ENTS,

For those of you who have worked with water chemistry, the Stiff Diagram is something with which you are likely familiar. A chemistry stub from Wikipedia: http://en.wikipedia.org/wiki/Stiff_pattern A Stiff Pattern (a.k.a. Stiff Diagram) is a graphical representation of chemical analyses, first developed by H.A. Stiff in 1951, and is most commonly used by hydrogeologists. A polygonal shape is created from four parallel horizontal axes extending on either side of a vertical zero axis. Cations are plotted in milliequivalents per liter on the left side of the zero axis, one to each horizontal axis, and anions are plotted on the right side. Stiff patterns are useful in making a rapid visual comparison between water from different sources.

I have used these many times in my hydrogeology career. The definition is somewhat misleading. The same format can be used to express the results of whatever chemical concentration information you have. In acid mine polluted water levels of Fe, Mn, and Al are added along with TDS (total dissolved solids) and pH.

I was thinking a similar approach could be done for individual trees. On one side would be plotted values for individual trees, while the other side would be plotted site information. Numbers for individual trees might include height, girth, crown spread, TDI, age, slope, elevation, tree density, etc.. While the general site information might include site size, Rucker height index, average annual temperature, average annual precipitation, latitude, longitude, diversity index, growing season length, etc.

What does anyone else think about this idea?

Ed Frank


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TOPIC: Stiff Diagrams
http://groups.google.com/group/entstrees/browse_thread/thread/fc861c611df2697e?hl=en
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== 1 of 6 ==
Date: Sat, Mar 8 2008 5:58 am
From: dbhguru@comcast.net


Ed,

The scale doesn't show up in th e-mail well enough for me to get a good visualization of what is being plotted. What is the vertical scale measuring for each horizontal band? Forgive me for being dense.

Bob


== 2 of 6 ==
Date: Sat, Mar 8 2008 7:32 am
From: "Edward Frank"


Bob,

On the image I enclosed the horizontal scale is in milliequivalents/liter with cations on one side and anions on the other. The vertical scale doesn't measure anything - just equal spaced units between the parameters sort of like bar graphs.

Think of a series of values plotted one unit apart as a set of bar graphs. You can have as many as you want and they don't all need to be the same scale. Think height, girth, etc. The scale for each can be individualized so that they all fit on the same plot. The fold the plot in the middle, with each side going outward from a central line representing a zero value. The left side increases to the left, the right side increases to the right. Now instead of bars change it to a line graph. The result is a form of a stiff diagram.

it is useful in water chemistry because you can see visually patterns that are not immediately apparent in the raw numbers or even in a standard horizontal graph. people are good at detecting patterns in visual presentations of data. In water chemistry, these are the primary anions and cations and the numbers on one side of the graph pretty much balance out each other. But the concept works for other unbalanced parameters as well.

On the graph I sent the chemicals are hard to read- generally one side is Ca, K, Mg, Na and the other is SO4, HCO3, CO3, and Cl.

But as I said other parameters can be used to reflect the data you have.

Ed


== 3 of 6 ==
Date: Sat, Mar 8 2008 7:32 am
From: "Joseph Zorzin"


Yuh, I'd like to see a full size version of that graph. By the way, it seems that you folks emphasize measurement of individual trees, but not so much the context of the forest that the tree is in.

We foresters, in theory, are supposed to be able to describe the entire stand. We tend to develop a sense of a stand as being good, poor, excellent- whatever. We get turned on by high quality stands even if the trees are young or not rare species. I can appreciate a strong love of and interest in exceptional trees, but I think you miss something if you fail to appreciate the wonders of a fine stand because it lacks gigantic or ancient trees.

It makes me think of the body builder crowd which ooos and ahhs over somebody like Arnold- but which might be missing subtle qualities in somebody with more modest dimensions but who excels in other ways.

One variable which says a lot about the future potential of a stand is site index. A stand might be modest looking- young and dense with common species, but if has a very high site index, a forester should be able to perceive the future exceptional forest.

It's the old canard of not seeing the forest for the trees. I can think of one stand of magnificent sugar maple in Pittsfield, Mass. The stand had been thinned previously, leaving only the nicest looking maples. By the time I marked the stand for a harvest- the largest maples were about 25" DBH. As individual trees, then, they were not particularly large. But, since they had been growing freely due to the previous thinning, and it was an exceptional site- they were incredibly vigorous. The bark on these trees was almost perfectly smooth- almost unheard of in sugar maples that size- almost as smooth as healthy beech- with a very attractive bluish-whitish-grey color. I think it would be unfortunate if tree lovers failed to see the beauty of these trees because they were not gigantic or extremely old.

Perhaps sites with such exceptional potential need to be protected in order to produce exceptional, large and old trees for the future. If you think how nice it is to find some old trees which happens to exist because they were left from old harvesting, or are in the middle of nowhere and thus inaccessible- possibly in areas with only a modest "site index"- just imagine what the Earth can do on exceptionally rich soils now occupied by farms and Walmarts. So, an addition to finding remaining old growth, we ought to be envisioning "future old growth" and where we can protect such properties for future generations to enjoy.

Now, if I could look forward to being around several centuries, I'd love to manage a stand starting with bare dirt- perhaps planting some trees and letting others come in on their own, then every 15-20 years, remove/harvest some. The goal wouldn't be to maximize timber revenue- the goal would be to produce a work of art- an forest which eventually would contain a wild mix of many species of many sizes. The focus would be on growing an aesthetic masterpiece- the stand that is, not individual trees- the forest would be my canvas. And, in that forest I'd place "object d'art"- sculpture, rock gardens and walls, etc.

The highest form of this "forest art" would be so sophisticated that it would simultaneously produce great timber value, over time- far more than occurs with the "run of the mill" of what passes for "forestry". I actually believe that this is what all foresters ought to do even if they can't stick around several centuries- passing the torch to others after several decades. After all, why should we treat Mother Nature any other way? For those who don't think of nature as Mother Nature, just contemplate that one day you'll die and be put back into the bosom of Mother Nature- believe it or not, you're going there. Of course most people who subscribe to this list, if not all, are nature lovers so they can appreciate this perspective- it's just unfortunate that we live in a society that prefers to trash the Earth to enjoy their selfish desires.

Currently, a forest that I did a nice thinning in 6 years ago is being trashed by a large "wood products firm" owned by a "professional licensed forester" and which has a full staff of "licensed professional foresters"- the owner is a guy who often rants against Mike Leonard and myself for "ranting" against timber beasts. I recall talking to Ross Morgan, a consultant in Vermont- he lamented the fact that many of the properties he managed for decades are now being trashed by the wood products industry with their "professional foresters"- and, Russ Richardson of W. VA has complained about the carbon industries in that state who planning on whacking many of his managed forests.

Is there any reason why we should not be ferociously angry about the continued destruction of the forests? Saving some remaining old growth won't help much the people of this planet in a century from now- a planet with double or triple the population and a lot more paved over landscape. But the few of us who aggressively speak up against the wood industry and their lackeys in government and the phony forestry "orgs" get little support.

'nuff ranting for this morning.

Joe



== 4 of 6 ==
Date: Sat, Mar 8 2008 11:50 am
From: James Parton


Joe,

I really like the way you think here. There is more to a forest than
it's individual trees. Trees do not have to be old or unusual to be
valuable and beautiful. ENTS site documentations should not be all
about how big trees are or how unusual a tree is but should have a
description of the forest as a whole. One must be able to see the
forest as well as the individual trees. The animals contained within
are also part of the forest biome as well.

James Parton


== 5 of 6 ==
Date: Sat, Mar 8 2008 12:34 pm
From: "Joseph Zorzin"


It's nice to be locate, document and enjoy special trees but if the other 99.99999% of the landscape is wasted, those tiny islands of special trees won't do much for the sorry inhabitants of this planet.

Joe


== 6 of 6 ==
Date: Sat, Mar 8 2008 5:49 pm
From: "Edward Frank"


Joe,

On first read I really have no disagreement with anything you say. In the original post I suggested that data for individual trees might be placed on one side and data for the site as a whole on the other. This would provide a visual graphical context for comparing the two. I am not sure how to implement the idea or even if it is workable. It would be good to get a standard format that incorporates common measurements in the top portion of the diagram, and less common could be added at the bottom. A second form could be made that simply compared various aspects of the site or forest as a whole instead of just one tree versus the whole.

That is why put the idea out there to get comments or ideas from others if they choose to think about it. I will pull together something, perhaps for some of the trees at Cook Forest, perhaps a graph for subsites at Cook and see what they look like. I will post the results. It might not be useful or lead to anything, but as a concept it seems workable.

Ed