Our inventory system up until now has used the 25-point condition rating as outlined in the 8th edition. In developing a conversion to an upgrade to our program, we came across a couple of anomalies in trying to convert 8th edition condition ratings to the 9th edition method.

1. Unlike the 8th edition, the 9th does not equate any narrative condition (excellent, good, fair, poor, etc.) with the points rating. Was any consideration made by the committee about past data being updated or equating the points (or percentage) to a narrative condition?

2. The smallest percentage rating a tree can have is 25% (8/32). The tree can be completely dead yet still have a condition rating of 25%. This doesn't appear to be a very logical number

Would appreciate anyones view on this. At the base level we understand why a narrative is no longer associated with a percentage rating, but the percentage rating in the 8th edition does not directly translate into the equivalent percentage in the 9th edition.

Reply to post by Mark Duntemann, on September 12, 2000 at 14:27:20:

Mark wrote: "1. Unlike the 8th edition, the 9th does not equate any narrative condition (excellent, good, fair, poor, etc.) with the points rating.
Was any consideration made by the committee about past data being updated or equating the points (or percentage) to a narrative
condition?"

Why would you want to update 8th Edition values? They were correct when they were done, and changing the rules after the fact is not correct. The appraised value of a tree is the value as of the moment when it was judged (with allowance for "before damages"). If you take an appraisal done two years ago and update it to 9th formulas, you invalidate the appraisal.

For inventroy work, you may want to update to a current value by applying the 9th formulas. In this case, you are not updating anything, but simply recalculating the value by current methods.

"2. The smallest percentage rating a tree can have is 25% (8/32). The tree can be completely dead yet still have a condition rating
of 25%. This doesn't appear to be a very logical number"

What many of these rating scales omit is the range to zero. If you apply a zero value to any of the factors, you will get a lower rating. The same thing applies to Methany & Clark's Hazard Rating- if you exclude zero as a rating, you only have a scale from 3 to 12 points- a bit limiting. Maybe not as important in that case, but the point is the same.

The condition rating in the 9th Guide is just a quick rating scale, not an absolute rule to be followed. It is, as has been said, just a guide to help with determining the Condition Rating.

Reply to post by Russ Carlson, on September 12, 2000 at 14:27:20:

Russ wrote: "Why would you want to update 8th Edition values? They were correct when they were done, and changing the rules after the fact is not correct. The appraised value of a tree is the value as of the moment when it was judged (with allowance for "before damages"). If you take an appraisal done two years ago and update it to 9th formulas, you invalidate the appraisal."

What's the underlying issue? If the 8th Edition value was correct when it was done and it varies from the (time adjusted) 9th Edition value doesn't the single tree appraiser or the broad scale resource manager need to understand and explain the difference? If what used to be right isn't right who says what's right now really is? There are either objective (i.e. fact based) explanations or the methods are simply arbitrary. If there is a fact based reason 9th is superior, then that is the reason you might want to update the values. And if your talking about thousands of trees in inventory it would be efficient to have a conversion algorithm rather that re-field appraising each tree.

Russ also wrote "The condition rating in the 9th Guide is just a quick rating scale, not an absolute rule to be followed. It is, as has been said, just a guide to help with determining the Condition Rating."

Same old three problems: 1) If it's just a guide, a guide, a guide then how can either of the two opinions (8th & 9th) be "right?" 2) If it's just a guide, a guide, a guide we wind up with no methodological consistency from guide to guide, from appraiser to appraiser or from region to region (see the earlier thread on Methodological vs Factual Determinations), 3) Even though it's a guide it's often percieved as a standard, results are often critiqued as if the methodology is standardized (but it isn't see #2).

Reply to post by Scott Cullen, on September 13, 2000 at 22:43:01:

Nothing here will require a re-inventory (if the software allows importing old records). The field data (fact) remains the same. The condition factor, however it was determined, can remain the same. If it was 78.25 percent when you did it using the 8th, why change it, especially if you have not revisited the tree. There does not have to be a direct correlation in the condition scales used. What is important is the condition rating that was applied, not so much how you arrived at it.

The point of which is 'right' cuts tot he heart of the question. The 9th edition offers a different method to reach a condition rating. Is this better? Worse? The same? A matter of opinion, IMO.

to the original comment on updating all the values, I'm still not convinced it should be done as a matter of course. There are situations (inventory, perhaps) where it might be applicable, but there should be a clear reason to do this, and it should not be an automatic process built into the software to update everything.

Reply to post by Russ Carlson, on September 14, 2000 at 06:57:59:

Russ, I think those were the specific reasons for Mark's query: A) inventories are the application B) users have identified a need to equate the values.

So if an 8th Edition scale came up with say 70% for a tree and 9th Edition scale comes up with say 62% for the same tree can we come up with algorithms or adjustment factors to equate the two scales?

Whether it's an automatic and global update to 9th, an automatic and global backdate to 8th, a second, parallell new value for the originals are all user management decisions.

Say for example a city was half inventoried using 8th. The second half will be completed using 9th. Wouldn't it be nice to know if the per tree or per inch average really was 20% different in the two halfs? Or a partcicular tree was valued with 8th, gets revauled with 9th. Did it really improve that much? Or conversely did it really drop in value so much it falls below our threshold for continued investment?

So, has anyone developed enough field experience to judge A) if the two editions develop differnt condition ratings and B) if they can be mathemetically equated? (I haven't.)