Tree dbh

[OneWithWood]

Guess I better work on that consistancy thang. ;)
Thanks for the advice Ron.  I stand a whopping 5'6", 5'7" on a tall day :D  So if I consistantly measure the tree on the high side where I touch it with my arm held at a 90degree angle I should get the consistancy should I not?
Sure am glad you more experienced guys are willing to share your knowledge with us more novice types.

[whitepe]

What is the dbh of the pig that's going to be roasted
on Aug. 7th 2004?

[OneWithWood]

Whitpe, I don't think that can be ascertained until August 5th. :D

[Joe_Beaulieu]

I have worked with several woodlot owners that practiced fairly intensive management techniques.  Marking certain crop trees at dbh with a reference mark (painted line) and a number(more paint) allowed them to closely monitor growth rates.  See Independent Sawmill & Woodlot Management, Oct/Nov. 2000 issue, p.40 for article on crop tree management.  

[Ron Wenrich]

Most of the landowners around here have the crop trees marked and then cut.  That leaves all that inferior crap to take over the next stand.  Diameter limit cuts are also popular.

[Kirk_Allen]

Jeff,
I agree with you.  I dint care to see paint on every tree in the woods either.

I can remember 10 years ago at my grandfathers farm on a sunny afternoon a stranger drives down the 1/4 mile lane to the farm house. (one way in- one way out)

We were on the front porch eating lunch and this guy gets out and proceeds to tell us that he just finished inspecting the timber on Grandpas west farm and had marked them so he could take a look and see which trees this guy wanted to buy.

Now you have to understand my grandfather.  He was a true Conservative in every aspect accept his trees.  Those were his trees and no one, and I mean no one was going to touch them let alone paint them.  That included family!  

If you can imagine a 95 year old man grabbing a ball bat from the back porch and chasing this guy off the property you will only get half the picture.  This guy was lucky to get out of there with his life.

Grandpa did manage to take out two headlights as the guy was backing out.  If he would have had his shotgun loaded in the garage he would have shot the guy.

I must say I was shocked to walk through the woods that afternoon.  Every tree over 10" was marked with brilliant orange paint and on some of them its still visible.

I think the next morning at the coffee shop an APB was put out on this guy.  Every farmer in wanted a piece of this guy.  Not so much for painting the trees as for having the nerve to trespass and think nothing of it.

Oh well, I know its kind of off topic but it brought back some memories.

[L. Wakefield]

   Oh, is that conservative? It is a perfect description of how I am and I've always been told I am paranoid and a total control freak  :D :D :D- I'l just tell them I'm a mite *conservative*.

   I know how the old gent felt, and I applaud his courage in letting his feelings be known.  lw

[Ron Scott]

Many of my clients are upset timber landowner's whereby soliciting timber buyers have gone on the private property and marked trees without asking the landowner in advance  for permission to do so.

Some quality stands have been marked with so many different colors by soliciting timber buyers that it sometimes becomes hard to find a color left to use when the landowner does give permission to do so.

Such paint markings without the landowner's permission often encourages the landowner's to seek out a consulting forester for advice on what's going on with paint marked trees showing up on their timber land.

I never mark any trees without prior written permission of the landowner to do so. This includes the permission of all who own the property, including the wife. To do otherwise without the landowner's permission is trespassing.

[Ron Wenrich]

I worked many years as a procurement forester.  Never, did I mark a tree without permission.  You don't need to mark trees to get an estimate of volume or value unless you don't know what you're doing.  

With experience, you can get a feel, just by walking through the woods.  But, I liked to do a quick cruse before talking to the landowner.  I would even write a quick management plan, if I thought it was a selling point.  Most landowners didn't object to walking through the woodlot or even taking a cruise.  They would enjoy finding things out about their woodlot.  Sometimes you bought the timber, most times you didn't.

Only once was I threatened with the cops.  A really old lady who didn't take to kindly to someone looking at her trees.  I told her if she wanted to call the cops, I would wait 'til they came.  

[Jeff]

If I had a woodlot and caught someone painting my trees or even cruising them without my prior permission, he would be begging me to call the cops, that is if he could still talk. I should say she also. I hear tell there are more and more female timber buyers out there. The one I know from this county gets the bad word from me to who ever asks. I found her at a harwood timber workshop a couple years back put on here in Harrison by MSU extention. She was there simply to see who showed up and potentialy spew her line of bull.

[SwampDonkey]

 ;D Here's my perspective  ;D

When working on the west coast of BC we did alot of timber cruising on Crown Lands for Lisence holders (those with cutting rights). BC has a timber cruising manual for crown lands which they are quite strict on and 3 major things that have to be followed per plot. They include cutting a plot centre stake tall enough to be at least dbh height when anchored in the ground, marking a reference tree below stump height (30 cm) which had bearing and distance to plot centre and plot number, and mark all dbh lines with paint after loose bark and moss has been removed on high side of the tree. DBH was always measured from point of germination. Also, trees where numbered clockwise from the direction you entered the plot along the measured stripline That was the easy part, now do all the pathology, quality and tree heights A plot typically took 45 minutes that had 6 or 8 trees to measure. Six plots a day was average and 8 was real good. More than 1 missed tree (in or out) found by the auditors from the MOF and it was a complete redo.

Anyhow, the painted dbh line was used for cruising audits by MOF staff and the reference tree was also for audits if there was ever any major dispute on the scale at the dry land sort. They could measure stump diameters and use treelength volume tables or the localized yield curves.

Never had to redo any of my work, but I did lots of other people's work over that got frustrated and quit   Well when you think of it, 1 missed Sitka spruce with 2.5 meter dbh and 70 m height represent alot of match sticks per ha

Here's the cruiser's manual:

http://www.for.gov.bc.ca/hva/manuals/cruising

They are currently working with the Assoc of BC Prof Foresters to get recognition for credited timber cruisers who have demonstrated their competance in cruising. There is an apprenticeship of sorts or depends on individual experience to become certified, and a peer review process. Member since 1996.

regards


Jeff, don't shoot me when I come a cruising your back woods ;)

[OneWithWood]

Occasionally I will get a call from a logging outfit wanting to know if I would like to sell some of my trees.  They always seem to know what is in my woods.  I always decline.  I don't wish to do business with someone who cruises my property without first contacting me.  I believe it is only common courtesy to ask permision before stepping onto provate ground.  If anyone was ever so bold as to mark the trees before talking to me you can bet I will have them in court for malicious tresspass.

[SwampDonkey]

hmmmm

I can' figure out why someone would be on your folk's property before asking you first. Who is paying them to go there and mark the trees? Are they cutting timber on your neighbors and taking time to scout properties bordering their operations? If so, they still should be asking first. Almost looks to me there are a few fly by night veneer buyers looking to get a sweet deal high grading your woodlots.

visit your woodlots often guys

[Frickman]

Just to put in my 2 cents worth, I never go onto a property without the landowners permission, to do otherwise is trespassing, as mentioned above. On every piece of timber we cut we try to notify the neighbors of our planned activity, sometimes you even get some more timber by doing so. Even if I see the neighboring property owner outside I will walk around and up their driveway rather than down through their woods. The worst way to start out a potential business relationship is to go around trespassing and getting the landowners mad at you.

[SwampDonkey]

Its important to note that dbh at 4.5 feet (1.3 meters) is the standard used to construct those standard yield curves (volume tables) used to determine stand basal area, density and volume. These standard yield curves are constructed by measuring a sample of trees for each species or species grouping which are representative of the forest land in your state, region or district. There are curves generated for any number of site indices (typically tree height @ age 50). Some jurisdictions use software programs to generate localized volume tables specific to the stand they cruise in, based on measured and estimated heights and diameters in the stand.

You can localize a standard volume table in the following way:
1)measure heights and dbh by species in the area for which the volumes will apply
2)prepare a curve of height over dbh by freehand method
3)read average heights from the curve for each dbh class (2-inch or cm)
4)interpolate from the standard volume table the volume of the tree of average height for each dbh class (or use the standard vol equation with the interpreted average tree height per dbh-class from above)



Steps 1-3 is represented by the first curve (freehand curve from sampled tree data in the woods), step 4 is the standard Vol equation with values interpreted from curve 1 to create curve 2. Big D is diameter and big H is height.

And you didn't think algebra was of any use way back in grade 8? ;)

Now all you need is tree diameters in that local area your working, to get volumes in future cruises.

I only do this for tresspass cuts, where I only have stumps on site, but I can measure neighboring stands to generate the localized volume tables. You can also use treelength tables. I have found that the relationship between stump height diameter and dbh is a straight line at 45 degrees with R^2 = ~ 0.95 for species in my area (Y=a+bX; a= y-intercept, b=slope). In regression statistics, the closer the line is to an R^2 =1, the better the fit ;)

Anyway that's enough statistics this round. ;)