Sustainable Forestry Initiative

[palogger]

I have taken some of the classes and I agree that forest management isn't stressed enough.  The problem in my area is that most of the timber has been mismanaged for so many years.  However when you speak to a landowner about doing improvement cutting, some of them don't understand why I want to leave a 14" red oak and cut a double hickory or hemlock. Alot of people are just concerned about how much can I make not what am I leaving behind for future regeneration. 

[BrandonTN]

Who was the SFI under before it broke away and became independent?

[SwampDonkey]

The SFI program, developed in 1994, is a project of the American Forest & Paper Association (AF&PA), an industry trade association.

http://www.afandpa.org/Content/NavigationMenu/Environment_and_Recycling/SFI/SFI.htm

[flatrock]

I am not a forester.  I do own forest land and I can tell you every sqaure mile around here has been cut by diameter limit multiple times.   And yes you can find multi-stemmed & crooked trees but there are plenty of nice straight trees also.   In my opinion loggers around here have no financial incentive to do  sustainable improvement type cuttings where the worst trees in every dbh class are cut unless it is done as part of a clearcut.  I think the majority of landowners want to leave a forest as good or better for their children.  At present the only types of cuts I have observed locally have been patch clearcutting on rotation and dia. limit cuts.  Diameter limit cuts are easy and I dont know if its based on science but the local custom is too cut high dia if you want to leave something for the grandkids and low dbh if you need as much money as possible.  Sometimes they have 2 dia. limits as part of the same harvest.  A low one for Hickory and a higher one for the oaks.
I am planning on doing something in the next 10 years when it will have been 30 years since the last 14" diameter limit cut on property I now own.  I would like to implement sustainable forest practices but as a private landowner with a small acreage (340 acres) I really dont know how feasable it will be.  Too confuse the issue further I have even found research suggesting diameter limit cuts in certain circumstances achieve the same goals as more sustainable type harvest practices.

[tonich]

As I’ve already mentioned, forestry is a very conservative science.
Thus, clear-cut system is one of the oldest and fully theoretically and practically proven. There is strong exactness for the size of cutting strips, consequence, cutting direction and mangling, hauling direction, methods of regenerations etc. And this is all examined, described and has been put into practice for many centuries.

Speaking of sustainable forestry, clear-cut silvicultural system doesn’t suit well. There are much better and newly developed systems which fully meet those requirements. The best one among them is the “Selective management”. This is probably the newest silvicultural system, occurred in Switzerland in the late of 19th century.

[Ron Wenrich]

Flatrock

I wouldn't consider 340 acres as acreage.  We have lots of woodlots under 10 acres and they are being worked.  Management may be a different story.

Your observations about diameter limit cutting is pretty accurate.  Industry pretty well lets the private landowners skate until its there is merchantable timber involved.  Then, they are the go to guys and seemingly know all there is to know about growing trees.

Diameter limit cutting is a good way to cut the best and leave the rest.  It takes your best performing trees and put them in the log yard.  It also limits genetics, since those better performing trees won't be reproducing.

The multiple stems that you are seeing is also due to a very hard cut.  To be fully productive, a stand should have a certain amount of acceptable growing stock per acre.  Foresters use basal area as a measurement.  That is the amount of square footage of tree volume at diameter at breast height.  To make it easy, foresters will use either a prism or an angle gauge to measure it.  I use an angle gauge with a factor of 10.  For every tree I count, there are 10 sq ft of per acre.  For most hardwoods, full stocking falls between 65 - 110.

When you are above that number, then your growth will start to slow.  Bole growth on hardwoods only comes about through crown expansion.  Above 110, and expansion isn't too good.  But, some of that stocking number is in suppressed trees.  Quite often the suppressed trees should be removed instead of being released. 

When you fall below 65, then your stand is understocked.  More sunlight falls on the forest floor and on the residual trees.  Underneath the trees bark are epicormic buds. These buds are stimulated by sunlight.  This is what is causing the multiple stems - too much sunlight.  You will also get branching on the remaining trees.   I'm sure you've seen forest trees that break out into sucker branches soon after a harvest.  Each one of those suckers are a defect in the lumber.  It takes about 20 years to heal them over.

If I was working on a 340 acre parcel, I would have it inventoried.  This should be done about every 10 years.  You will find that your parcel also has several different forests within it.  They should all be treated differently.  My advice is to get an inventory and management plan started now, and don't wait another 10 years.  There's probably some good management work that can be done now, and allow those keepers in the woods for several more years.

A well managed forest should be able to give a harvest every 10-15 years, not every other generation.   ;)

[flatrock]

Attached is one dia. limit study.  There are also just as many negative studies.  Many landowners cannot afford a inventory unless its part of marking/sale.  There has never been a harvest on our property since the 1940s without the input of a degreed registered forester ,including the 14" dbh dia. limit cut 20 years ago.  I realize silvicutural thinking/theory evolves and it makes pefect sense to me that sustainable selective type cuts are the way to go.  I just see problems managing & implementing it as a practical manner.  I think your going to have a hard time keeping some logging companies from cutting down a nice 15" tree in the thick of the back 40 marked or not.  Im in no hurry but right now Im leaning more toward large group selection cuts or  small patch clearcuts in areas selected by a forester and doing 1/3rd of the property on a periodic basis every 20 to 30 years.    It would seem to be easier to manage, produce the most sprouting, provide pockets of stimulative sunlight, & gradually shift the forest into different age classes.  However, Im giving myself a decade or so to mull it all out and intend to have both a state & private consulting forester walk the property and give me their opinions and will likkely follow their recommendations. 

[SwampDonkey]

Was just on a 20 acre parcel of forest in the middle of potato ground. It was 80 % beech and all diseased and a lot of rot and dead limbs. The rest was mainly pole sized sugar maple, white ash, yellow birch, balsam fir and butternut. The owner could sell to the farmer, and by the way it is for say, and clear for additional field or do a group selection to promote regen of other hardwood species besides beech. Beech will always be a component, or for longer than I will be alive. But, if you tried to do a selection and take all the junk, then you'd have a pretty sickly stand of wood left. A few less beech, but still a high component of it. I think the only reason it has stood this long is the price is too high. A mill doesn't want rotten wood and you can't pay a high stumpage price to just cut junk.

[Ron Wenrich]

Your study attachment didn't come up, but like you say, you can find studies to support either side of an issue. 

Nobody said that an inventory has to be conducted by a forester.  You can do it yourself, if you like.  Here's a tutorial we have on the subject: (look at the point sampling)  https://forestryforum.com/tips/tips.cgi?Forestry

There are all types of ways to manage a forest.  You can do group selection or you can do single tree selection.  It depends on what you want from your forest.  If you're sold on diameter limit as a management criteria, that will work too.  Diameter limits can work if you are using it in the context of shelterwood regeneration.  Quite often the inventory can give you a pretty good idea on which way to go. 

The hardest part of forest management is trying to decide what you want to grow.  We've had an oak mentality for a long time.  I was around before red oak was a desirable species.  Red oak has now lost its luster.  Maple was considered a weed species just 15 years ago, but is now worth much more than red oak.  Patch clearcut for maple?

Was managing for red oak a bad idea?  I don't know, but managing future forests for current markets always have pitfalls.

[Phorester]

A forest is a collection of plants.  Individual tress in a forest, and the whole forest itself, grows according to basic biological principles.

A diameter limit cut is not based on any biological principle whatsoever.  It's based only on the physical size of the trees.

The landowner controls what occurs in his forest.  It is the landowners choice to manage his forest based on biology or his pocketbook.  The forest suffers for the next owner and for society if management is based on how much money the current landowner can put in his pocket instead of biology.

A Forester working for the landowner can only do what the landowner allows the forester to do.  If the landowner says, I want a lot of money from a timber sale, the Forester is obligated to provide that for the landowner.  He has to satisfy his client.  Or he has the option of walking away.  Walking away is easy for us government service Foresters because we get paid no matter what we recommend to the landowner. But few Consulting foresters have that option because their income to feed their families and pay their mortgage doesn't come in by turning down a job.  Hopefully, a concensious consultant will try to work in as much good forestry as he can while making money for the landowner.

But the bottom line with cutting trees in a forest.... it can (and should) be done based on sound biological principles.  Diameter limit cuts do not accomplish that. 

Diameter limit cuts are a slow death for a forest.

[Ron Scott]

Ditto! to the above replies.

The premise that the "diameter you cut down to" is what determines good timber management is not good forestry. Diameter limit cutting is usually destructive, no matter what diameter is chosen. Why? Because it degrades the stand of timber. Stands cut in this manner require several decades to heal.

Tree diameter is only one indication of whether the tree should be harvested. Health, vigor, age, stand density and species are among the many factors needed for consideration. In most cases, the best quality trees should be retained. These are called "crop trees". The trees to be harvested include the trees declining in health and vigor, defective or diseased.

Diameter limit cutting, or simply " cutting the best and leaving the rest" is not sound forestry.

I do "turn down consulting jobs" when I consider that a potential client wants to practice "bad forestry". A professional consulting forester isn't needed in such cases and I won't put my name on it.

[Tillaway]

We have modified the traditional diameter limit cuts and do them regularly now.  Instead of the traditional cut all trees of whatever species over a certain size we flip it and say under a certain size.  We use the cruise data and the foresters observations to determine a residual basal area target.  Typically for our area all the trees are of the same age so usually the largest diameters are your dominates and co-doms.  The top diameter limit is selected by species from the cruise data to meet the residual goals.  We get a somewhat patchy thinning as a result but it easily falls with our management plan objectives.  Our goal is to leave a mosaic of stand structures throughout the forest.

I can understand the dislike for diameter limit cuts but there are other ways of using them to actually improve stand structure and vigor.  I think the key to implementing them is to be working in an even aged stand.  An uneven aged management regime would be nearly impossible to get the kind of results we do.

[tonich]

@ Tillaway:
Would you please tell us, what kind of stands you manage by diameter limit cuts – tree compositions, age rotations, management goals, maximum diameter etc.
As a noob here, I’m not familiar to this “diameter limit cuts”.   ;) ;D

[Ron Wenrich]

Diameter limit cutting is usually confined to taking all trees above a certain diameter.  Its pretty common in hardwood stands where there is little management done.  Its easy to administer and it takes all the good stuff out, leaving the rest.

In Tillaway's example, they are using it as a means of removing the worst and setting the diameter limit as the upper limit to cut, instead of a lower limit.  It should look more like a shelterwood cut. 

I've seen hardwood shelterwood cuts done like this.  But, works mainly in a one or two age class stand.

[Tillaway]

What Ron W said. We have basically 300,000+ acres of a single age class that is of poor vigor due to overstocking, poor seed, etc.  We have pretty much just one or two species in our stand composition.  The results can be patchy with thickets left in areas and small opening created in others.  Our goal is to get a stand with varied ages and mixed species, with several different layers in the canopy.  We are trying to introduce Older forest Structure into a relatively young even aged stands.

To really confuse things we also have been doing diameter limits with a thinning leaving say 140 BA.  The instructions for something like that is " cut all Doug fir below 17" and thin whats left to 140 BA."  I tell the fallers to cut all the Doug fir up to 17" and then keep cutting till you get a 7 count.  If you don't make the count because all the trees were all small then that's not a problem.  We want holes.  These type of cuts a really hard to administer, fortunately we have some really good fallers.