Hardwood even-aged/un-even aged

[flatrock]

I see alot of material regarding un-even aged mgmt. in hardwoods and I have a few questions I hope the board may have ideals on. My first question is, if your forest is primarily a stand of even-aged shade intolerant species is  un-even aged mgmt. still the right approach?  I have a tract of oak/hickory no maples, cherry or other commerical shade tolerant species.  I would think scattered group selection openings or small clearcuts would be a better way to maintain the oak species.   It seems you would get the stump sprouting from the smaller stems harvested as well as lots of sunlight. Or, is there an uneven aged method that really opens up the canopy and would work in regenerating with shade intolerant species like oak?   Presently the dominant harvest method in the community where my forest is located is the diameter limit cut.  The higher diameter limit cuts that I have seen (14" or 16") to me look visually appealing quicker after harvest but every thing I read indicates this is the worst possible way to harvest and you are condemning your forest to decline by doing this.  Which leads to my final question. In even-aged stands  of shade  intolerant hardwoods is diameter limiting cutting or some variation of diameter limit cutting ever the best harvest strategy?

[Ron Wenrich]

Its really hard to convert over from an even aged forest to that of an uneven aged.  Your group selection would be one method.  Think of your forest as being a lot of smaller forests that are managed at different ages.  This can also work for other species, but you have to vary the size of your openings, depending on the species you're trying to regenerate.

One of the hardest thing to get through people's head is the need for regeneration cuts.  I have been on several jobs that have no regeneration.  They had a "thinning" which they were told would result in a new forest.  But, if the thinning is too hard, and the openings are too big, then you end up with weeds and vines with very little chance for natural regeneration.  Stump sprouts are not necessarily a good regeneration source.  They usually end up with multiple sprouts or deformed butts.

Diameter limit cutting is silvicultural suicide.  If you are working in an even aged forest, then you will be taking all the good growing trees and leaving the slower growing trees as a seed source.  If they couldn't beat out the other trees when they were juvenille, do you really think they are a good seed source?  Never kill your best milkers. 

When you cut at 18" and up, you are taking the cream of the crop.  That is where hardwoods make the veneer grade. 

There are some regeneration cuts that use a diameter limit cut.  You cut all trees under a certain size.  That allows them to seed in under a canopy of good quality trees.  Then, you remove the overstory and release the seedlings.  It doesn't happen very often on private lands. 

[LeeB]

Very interesting topic. I didn't know I need this information till now.

[Gary_C]

How do you determine if you have an even aged forest vs. an un even aged. Certainly not by same diameters. Is it height of trees?

[SwampDonkey]

Red oak is not as intolerant to shade as our aspen and whit birch here in the north. Red oak lives at least twice as long as aspen. I can't really say that about white birch as a general rule because we have some really old white birch on good sites to. A lot of those old bruits died off here 70 years ago, but you still find the odd one. Getting back to red oak shade tolerance, it's considered intermediate like our yellow birch. In this area red oak and yellow birch alike do best on sites with a fluctuating water table on finely textured soil with good lateral flow. And associated with sugar maple, yellow birch, white ash and basswood and commonly with softwood such as balsam and white pine. Usually, small, relatively pure stands of red oak are found on shallow rocky soils. Right now I'm thinking of the sites I know with almost pure red oak and it fits those shallow rock outcropped soils, usually on ridge tops or southerly aspects of big hills. It's regenerating well on my woodlot, which was clearcut in 1993 and never had an oak on it until the wildlife and myself planted them. I blame bear and moose and maybe the odd blue jay as I'm not far from a pure stand of red oak. Neighboring woodlots that were cut at the same vintage as mine have some oak seeding in to. We aren't talking huge numbers, but they are common. I try to save every one.

As Ron says size of harvested openings means a lot. Big open areas cut on rich sites can mean poor regen and lots of raspberry, elder, weeds and such. I would limit the open sizes to a couple tree lengths and smaller, but go for irregularity of the shape of the opening. Most often if your opening a mature stand of red oak up there was no regen under it, due to shade.  Possibly, you release the seed of some weed species that may be dormant for decades or get wind blown seed coming in of undesirable species.

As Ron says, avoid the diameter limit game. Short term gain for long term demise. That's what we have experienced on most active woodlots here in my area. On lots with a long cutting history, Hardwood have been high graded to death or simply cleared off. Those best trees split a lot easier than the knarly ones for firewood. We never really had much of a hardwood sawlog market here until the last 15 years. It was pulp and firewood. Thousands of acres chewed up by chipping operations for peanuts on crown lands and 100" or treelength off harvested woodlots.

You should always do a preliminary inventory before you go toting a chainsaw. Get a feel for the quality of the standing trees, the density and distribution of tree diameters and ages. Then, plan the cutting to improve the stand quality by taking so many trees or basal area of each diameter class and age group and encourage a wide range of each so you can make multiple entries to your woods in your life time. And not just one entry that you may regret down the road. What good is a family woodlot to the family if you have to wait 2 more generations for the next crop? It likely won't stay with the family long. That's what I see here a lot. People just move on and sell out without worrying about the next guy.

I know I rambled on a bit more than necessary, but food for thought. 

[SwampDonkey]

How do you determine if you have an even aged forest vs. an un even aged. Certainly not by same diameters. Is it height of trees?

Height is a pretty good guess for pure stands of some species if the trees being assessed are free to grow, not over topped or show signs of long suppression and the soil type is similar. I wouldn't rely too heavily on it in mixed stands. That little balsam could be 50 years old and 6 feet tall, while that aspen over there is 15 years old and 50 feet tall.  Well managed balsam fir stands growing on a known soil type are known to achieve a certain size at a known age, that's just site index.

Get out the 'inky' borer, tried and true. 

[Phorester]

GARY, the definition we use in VA: an evenaged forest is one in which the dominant trees are all within a 20 year age spread.  You cannot go by height or by diameter.  You need to count the rings.  We use an increment borer (Swamp's "inky" borer) for that.

About height and diameter,  first you have to compare trees of roughly the same age.  Then, height is determined by the site.  Good sites produce tall trees, poor sites produce short ones.  Diameter is determined by growing space.  That's why thinning is important. You give more growing space to the trees you want on that spot so they grow faster in diameter than if they were not thinned.  Thinning produces a faster growing tree, thus a healthier tree and one that reaches commercial value quicker.

FLATROCK:  In the hundreds of management plans I have written over 33 years, I have recommended a diameter limit cut only once.  It was in a 25 acre stand of almost pure chestnut oak, evenaged.  Since all the trees were the same species and the same age, growing on the same soil,  a diameter limit cut would work there.

Otherwise it is indeed a slow decline in the health and commercial value of a forest, as Ron describes.  It's the worst way to harvest timber if the landowner is at all interested in the future health and value of his forest. 

[tonich]

GARY, the definition we use in VA: an evenaged forest is one in which the dominant trees are all within a 20 year age spread.   

Looks like the same here, in BG.
We have so called “age classes”, which are as just as Phorester described them – 20 years for high-stem management, and 5 years for low-stem management (coppice stand).

As for uneven management: You really need strong shade tolerant tree species, in order to introduce it successfully. Although Red Oak is less light demanding, comparing to our local oaks, I would never consider it a shade tolerant tree…
There were some efforts in the past for turning oakeries into uneven management, which were not so successful. The general rule is: If you need uneven-aged forest, deal with shade tolerant trees for it!

Red Oak is supposed to be the leading tree species in you stand, I assume. Others should be spouses. The approach should be everything, but diameter limit cutting.
After I’ve been described this method, I can only second:

Diameter limit cutting is silvicultural suicide

[Gary_C]

Thank you for the replies. Would it be true that just about all uneven aged stands are created by man and not the result of natural events?

[tonich]

Would it be true that just about all uneven aged stands are created by man and not the result of natural events?

No.
Uneven-age forest appeared by nature originally. With no human disturbance.
Small gaps are being opened by biotic and abiotic factors, causing start of self-regeneration process on very small area. Repeating this many times, leads to complex pattern of tree of different age and dimensions
It is man, that is trying to follow natural processes nowadays, by means of so called Uneven-age Management.

[Ron Wenrich]

I had a guy try to tell me he could prove that there was no such thing as forest succession due to shade intolerance.  It was also the basis for his perceived notion that forest science was just a bunch of hooey.

His facts were that he was on the Tionesta wilderness in NW Pennsylvania.  The area is a virgin forest.  He came upon a spot that had a white pine and a hemlock growing side by side.  How could that be?  Isn't the hemlock shade tolerant and the white pine shade intolerant?

My reply was imagine 2 seedlings standing underneath a really large hemlock or other such tree.  Now imagine a lightnings stike killing the big tree.  An opening appears and both the shade tolerant and shade intolerant trees are released.  His reply was "Never thought of that".

The point is, a lot of those shade intolerant species remain viable in the understory for a very long time.  All it takes is some sort of natural calamity to release new trees.  That could be a fire, ice storm, tornado, flood, etc.  Depending on how old the forest, there should be several different ages present, along with a lot of different species. 

[tonich]

The point is, a lot of those shade intolerant species remain viable in the understory for a very long time. 

Yes, this is what Uneven-aged management is based on.
But I was considering mainly shade tolerant tree species, though:

I wouldn’t consider any small size tree a “junk”, since it is the future stand of the selected wood. For example the Silver Fir (Abies Alba) is able to stay/be kept suppressed (selective cutting is a combination of suppressing and releasing) for up to 70 years of age, without loosing its growing potential at all.

(http://www.forestryforum.com/board/index.php?topic=24761.0)

[Tom]

I'm told that release is viable only to a certain age.  Pine that has been "Stunted" will not respond to release after a few years. (not my statement)

If this were true, would hardwoods find themselves permantly stunted?

Now, I have to add that I've cut many pines from swamps that had twenty or thirty growth rings in their first 3 inches of growth and still burst out into 1" rings and make a 20" tree after a supposed release.  Would this be a normal thing?

[SwampDonkey]

Balsam fir is notorious for sitting in suppression for decades and live on. Once released it can take 5 or 6 years before growth rate picks up. Those trees are usually rotten in the middle. If you can catch them by 25 years or so, and release them they will be a lot better tree. On the other hand red spruce will respond well from long suppression and not suffer from but rot so much. White ash, which I've posted a pic of the end grain, shows one board that had rings about 25 to the inch, yet it became a dominant tree. It is quite shade tolerant as a young tree, becoming less shade tolerant with age. Similar to white pine. Nothing could be more shading than 7 foot tall raspberry canes over topping white pine seedlings. I have some in that situation that are still green, but grow very little. The seedlings would be 7 years old now and compound this with browsing by snow shoe hare. It's amazing how they live. 

[Ron Wenrich]

I've always heard the same thing.  I think all trees respond, just some respond slower.  Now, if they respond too slow, they'll get overtopped again.  It probably has something to do with juvenille trees vs older trees.  

I've seen the same rings in oak trees.  I once gave a talk to a 5th grade class about trees.  So, I took in a cross section of a tree.  About the only person that was interested was the teacher, and she was amazed.  From the rings, I could tell when the stand was probably cut, and when there was a hard gypsy moth defoliation.  Each time, the tree responded to the release.

The only time a tree will expand its diameter is when it has room to expand its crown.  

[Gary_C]

So that leads me to the next question. Are all even aged stands only the ones created by man as in plantations or pure stands of aspen after clearcuts? Are you saying that all even aged stands will revert to uneven aged in time?

[Ron Wenrich]

I would think the incoming forests after Mt St Helens would qualify as an even-aged stand.  Same goes for a lot of ingrowth after a forest fire.  A lot would depend on how big of an area you want to classify as a forest.  If you are looking at a rather small area, then the amount of trees you have to work with are limited.

Will an even aged stand revert to uneven aged?  I would think that depends on the amount of outside influences and the size of the disturbance.  Minor disturbances would tend to more uneven aged structure.  Major disturbances would tend to more even aged.

[Tom]

Still, inversly, a stand of highly invasive, fast-growing trees will form a dense forest that disallows or chokes out any competitors.  Brought to mind is Chinese Tallow where there is no outside disturbance.  I've seen acres of it come up almost simultaneously and be so dense that nothing, including its own progeny, can survive in the shade below.

[flatrock]

Thanks for all the replies.  Have made me think of other questions.  I understand the need not to wipe out all the big ones for genetics.  So, then is the trick in a southern oak hardwood dominated even aged stand cutting a little heavier across diameter classes to let the sun in?  Im thinking of the forestry term residual basal area.  Assuming adequate stocking to begin with cut to lower RBA than say you would in the NE and harvest across diameter classes.?  My concern here would be the smaller stems are really the same age as the bigger ones.  Is the reason they are smaller due to genetics and will an even aged cut like this leave  a forest with smaller trees that have bad genetics as well as good big ones.  If the small trees do not respond  & grow well it would seem the better course of action would be large group selection cuts.

[SwampDonkey]

Again, I can think of aspen stands. Often I come across sites copiously regenerating with aspen at a density approaching 20,000 stems per acre. Hmmm.....through self thinning from over crowding, competition, shade intolerance, and cankers the stand density declines with age and height. Low and behold in 10 years time I see a carpet of sugar maple.  or a carpet of balsam fir establishing even more  Very shade tolerant tree species will establish at the 'opportune' moment. 

Go to a hardwood stand, mixed with sugar maple, beech and yellow birch.....concentrate on harvesting the beech out for firewood while leaving the maple and yellow birch in the canopy and retaining 60% plus crown closure. See what the regen is in 10 years. Beeeeeeech!!  So thick and nasty you can't begin to walk through it.

[Phorester]

FLATROCK, the smaller trees could indeed be small because of genetics, which usually translates into vigor of the trees.  The most vigorous tree will have an advantage over a less vigorous tree, but only if it has enough sunlight. With dominant trees of the same species, most likely the smaller trees are small because other trees got a head start on them.  Since trees in an evenaged forest can be as much as 20 years apart, one tree could have several years headstart on the tree next to it, capturing the sunlight first and growing in height all those years before the other tree even got started.  It's all about sunlight.  Whichever tree gets the most of it wins.  Forest management is really about manupilating sunlight in a forest.

As far as letting sunlight into a southeren/eastern hardwood forest, there really is no reason to do this, until you are ready to regenerate that particular area of the forest.  In fact it could be a detriment since it would favor the establishment of shade tolerant species (maple, gum, hickory etc.) over the shade intolerant species (oak, ash, walnut,etc.)  When the point in the life of a forest is reached where it needs to be regenerated, then there are different cutting techniques used to create the conditions needed to get the regeneration needed.  Shelterwood cuts, clearcuts are the two most commonly used in eastern/southern hardwood forests to regenerate them to oak, ash, etc. 

[Geoff Kegerreis]

It is unbelievably amazing how many different opinions there on this topic.
It is equally unbelievable to me how much information is lacking on nearly every one of these opinions.

Maybe that has to do with the fact that such a concept is the topic of several different kinds of books.

My suggestion is for you to read the most current and up to date manual I am aware of to educated yourself more about the topic.

That book is available from the Ontario Ministry of Natural Resources (actually, it's two books - they are complimentary of each other).

The Silvicultural and marking guides of Tolerant hardwoods working groups.  Those two books will introduce you to the concepts of uneven aged forest management. 

As for prescribing and marking Southern or Central US hardwoods under the uneven aged management system, research what other professionals have been doing over the last couple of decades.  There is all kinds of information regarding this topic.  The problem for discussing such a topic here is that it is too complex (requires a lot more information) for this sort of discussion.

Contact for addressing your questions: Clint Trammel of Rolla, Missouri.  Clint recently retired after working for 37 storied years applying uneven-aged forest management techniques at the Pioneer Forest in Missouri.  clinttrammel@gmail.com.  Tell him a "Guild member" sent you.  He'll get it.

[Tom]

Why don't you invite Clint to join us? 

[tonich]

It is equally unbelievable to me how much information is lacking on nearly every one of these opinions.

It is amazing, how respect is lacking on your statement!


Mate,
If you are intended to state something on the topic, please do it!
DO NOT send anyone here to gather information from whoever! Please!

[Ron Wenrich]

Apparently, everything you need to know about forestry is in some book.  We just haven't read the right ones.   

[Geoff Kegerreis]

It is equally unbelievable to me how much information is lacking on nearly every one of these opinions.

It is amazing, how respect is lacking on your statement!

Sorry, but I call them like I see them.  Look back at the whole of the responses and it's practically almost as if everyone is guessing.  Either that, or they're repeating what their SAF inspired silviculture professor told them while in college. 

To someone who has managed Oak/Hickory and other types uneven aged, followed the silviculture appropriately and taken a look at dozens of different stands in which uneven aged techniques have been used - and those that haven't (focusing on the management, not on which logs I can get to the mill), I'm pretty sure I know a thing or two about this topic.  The problem is: How can you share the information when you're not on the ground?  Narrated video would be the best medium, but that takes significant time and time is money.  Nobody has a show out there like that because from the "big picture", only a small % of the population cares.

There are a lot of questions that are perfectly answerable on this forum.  Most of them are, but this one needs more info than the medium is capable of.

I have a timber sale in Southwest Tennessee that I marked toward an uneven age regime over the winter and sold during the spring.  There were at least 12 different species of Oaks on that property, along with the usual Sweet gum, Yellow poplar, Red and Sugar maples, and several different species of Hickories along with some others.  It should be cut next spring/summer.  Assuming the economy and nature (and a quality logging job is done) are fairly stable during the next two decades, by the 20 year mark, this guy will be sitting pretty for another thinning.

Summarized uneven aged management on intolerant types involves 1. keeping quality trees on the ground by using single tree and group selection by reducing crop tree crown competition. 2. keeping crown density optimized based on the silviculture of the species surrounding the crop trees (optimizing crown maintenance, shading of stems to prevent epicormic branching).  3. Ensuring canopy gaps of the right size, placement (azimuth & aspect) and number to be maintained over the cutting cycle span are utilized for regenerating the species.  Don't forget about biological diversity, including seed vector management (management of squirrels is important in these cover types).  The whole practice is site-specific and depends on what is growing on-site, the soil types associated with potential vegetation phases and lots of other information.  It also depends on how good the logging crew is with their equipment (obviously).

As it has been previously mentioned, most of the trees in these stands are approximately the same age, even if the diameters vary significantly.  The history of the site is obviously important, but on most sites, genetic diversity within a species has little (as in negligible) to do with this fact, it is almost all leaf placement and crown position during the growing cycle.

The problem with summarizing this procedure is that an enormous amount of information is put into making decisions on what trees stay and how those trees are to be maintained.  Marketing stands that have been managed like this might not go as well as one hoped either, since in most of the Oak/Hickory areas, the mentality is "clear cut" in 100 year rotations or cut the best and leave the rest, or possibly, a non-silvicultural "select" thinning. 

When 100% of the market is based on harvesting projects that are highly efficient from a short-term financial perspective, it is hard to get anyone to look at forest management that can increase the quality and form of future trees, even if what is marked for this entry level is by all means certainly merchantable.

Mate,
If you are intended to state something on the topic, please do it!

I already did.

DO NOT send anyone here to gather information from whoever! Please!

If someone has an answer to another's question, why not offer that person's name?  This may be surprising to you all, but there are some folks who aren't interested in spending the time on forums, but would rather concentrate their interest toward their work in the field and answer questions in an e-mail so their time can be kept efficient.

This particular topic is site specific really - much of forest management is - I can appreciate your interest for mass dissemination of information, really I can - but there is a lot of information that will not possible to discuss on forums like this.  Seriously - it's just not practical.

To Ron Wenrich: Perhaps we will all be able to read Clint's book, should he write one.  There are multiple ways to gain knowledge in this field.  The most efficient way to gain the knowledge is to read a book written by experts who have obvious practical experience.  The highest quality lesson would be to have a few months with someone who has already done this for several decades, read what was done from the records and see the results.  I offered appropriate advice.  Apparently, some of you folks have another idea of what good advice is and cannot stop yourselves from making sarcastic wisecrack responses if your idea of good advice isn't offered.  So be it.  I've got broad shoulders.

[Bro. Noble]

Maybe if you start acting nice,  Ron would let you tag along behind him and learn a little of what he has gained not only from the books, but from a lifetime of experience as a forester and sawmiller.  If you have followed this forum at all,  and have above average intelligence,  you would have the respect for Ron's comments and opinions that the rest of us do.  You kids with fresh degrees are pretty boring sometimes.

[SwampDonkey]

Summarized uneven aged management on intolerant types involves 1. keeping quality trees on the ground by using single tree and group selection by reducing crop tree crown competition. 2. keeping crown density optimized based on the silviculture of the species surrounding the crop trees (optimizing crown maintenance, shading of stems to prevent epicormic branching).  3. Ensuring canopy gaps of the right size, placement (azimuth & aspect) and number to be maintained over the cutting cycle span are utilized for regenerating the species.  Don't forget about biological diversity, including seed vector management (management of squirrels is important in these cover types).  The whole practice is site-specific and depends on what is growing on-site, the soil types associated with potential vegetation phases and lots of other information.  It also depends on how good the logging crew is with their equipment (obviously).

Good answer, but seems I've read it many times on this forum already. If you regurgitate what has already been written in this thread and others similar to it, I'm sure you will see it. 

+++++++++++++++++++++++++++++++++++++++++++++++++++++

Sorry, but I call them like I see them.  Look back at the whole of the responses and it's practically almost as if everyone is guessing. 


The most efficient way to gain the knowledge is to read a book written by experts who have obvious practical experience.  The highest quality lesson would be to have a few months with someone who has already done this for several decades, read what was done from the records and see the results.


It is unbelievably amazing how many different opinions there on this topic.
It is equally unbelievable to me how much information is lacking on nearly every one of these opinions.

Geoff, Try to be a little less brazen and bold with your assertions/comments. Your about my age, and I agree 15 years experience is significant and a bit more experienced than a fresh college kid. But, there are some of us on here with decades more experience and if you don't get the answer you agree with, there is no call to shoot someone down. You can disagree, but be a bit more congenial about it for the sake of the forum spirit we are used to.  Sometimes the answer to a question has been typed many times in different threads. Maybe someone is not up to typing it for the 10th time and wished they had a button to push that would bring it all together and sort the more relevant portions from there typings.  Some of us kind of dodge the answer and ramble with our life experiences a bit. Guilty as charged.  Might even end up cooking donuts or making sausage before the thread is over. The reader can sort what's relevant from someone's personal dictation/ramblings. You might find folks a little easier to get along with if you loosen up the belt a notch or two. Otherwise, I'm afraid it isn't going to go too good my friend. 

[Sprucegum]

This is an interesting thread. Being an eclectic reader I have enjoyed the uneducated opinions as well as the educated ones  Part of life's lesson is learning to absorb both and discerning which avenue is more appropriate.

Geoff, your last post was well written. Thank you for taking the time. Those broad shoulders are handy for carrying chips, eh?    

[flatrock]

First of all thanks to everyone who replied.  I learned something from all of the replies.  I appreciate it very much.  I realize I did not give much information regarding the stand in question so here goes.  The forested tract is 250 acres in size & part of a larger acreage & is located roughly 150 miles west of Memphis & 25 miles south of the Mo. border in the Ozark foothills of Arkansas.  The area has a reputation for producing alot of low grade to avg. hardwood for ties, decking, etc.   The particular stand Im interested in is 60 acres in size and lays along the gently sloping side of a large hollow and has a NE aspect.  The site index is 80 for redoak which it the dominant species in the stand.  The stand was cut as part of a property wide cut to a 14" diameter limit in 92 ( I did not own the property of have control over harvest method at that time).   My understanding is that most of the logs went to a large flooring mfr.  Prior to that it was not cut back to at least 1951 perhaps longer.  Both private & consulting foresters have recently told me this stand is well stocked and have been told by more than one forester that it is one of the best red oak stands in this county.   I frequently am in this area hunting & my guess would be the avg. dia. now is somehwere between 16" to 18".  I have personally measured with a dbh tape several 20" and of course there are smaller diameters as well.  I have read quite a bit about the pioneer forest but my understanding is their technique works well there because they have a more xeric area,a large component of white oak, and a lower site index.  I would say my site is more mesic than theirs.  I like the single tree concept but you have to marry it with reality---what will be the consulting forester marking cost, can the logging crews cut without damaging etc.   Of course, I want to walk away with some cash but I also want to leave the forest stand in a state where hopefully my children in 20 to 30 years can walk away with some cash.  As of right now Im considering both the group selection as well as some variant of the single tree method. Optimum group selection opening size  & residual basal area are question marks.  Assuming I dont die I plan to harvest again if its ready in 10 to 15 years  again as part of a larger property wide harvest.  In the interim I am starting to weed out the noncommercial understory thinking the reduced competition will favor oak regen. at harvest.  My hope is that in the time before next harvest more specific silvivultural prescriptions will be developed for this area and I can hire a good consulting forester who can worry about all this & take care of it for me.  Again, thanks for all the replies.

[Mooseherder]

Wow, the big enchilada has put a shoulder to the door. We don't forget who put us here Jack, thats page one.
Now you got your turn, put away the whistle. Watch and learn junior. People don't care how much you know, they want to know how much you care.
Don't crash the ambulance whatever you do.

[Gary_C]

I saw an interview with Alan Greenspan recently when he was promoting his new book. At the end of the interview Greenspan was asked what were his plans were now that his book was finished and he immediately replied that he was going to continue learning everything he could.

I feel the same way and so now that we are through this little diversion, it's time to get back to the subject. 

I somewhat agree with Geoff that there was not much information offered in all the responses, at least to my questions. However I concluded that this even/uneven label is relatively unimportant in determining the best management plan for any tract. As a forester would be crusing the plot, the label would not even be in top five things you would be thinking about when you determine which trees to remove or save. Far more important would be desired species, basal area, diameters, placing in the plot, shade tolerance, etc. In other words the label may be important in the classroom, but not on the ground. Or am I trying to over simplify this?

The reason I ask these questions is, as I am cutting my usual thinning jobs, I try to understand as much as I can about what the forester was trying to accomplish. The last job I cut was listed as the first step in a two step shelterwood and site is supposed to be either chemically and/or mechanically site prepared and planted to Red Oak. Unfortunately about a year before I was able to start, a storm went thru the area and blew down many trees. So the forester and I had to make some adjustments as I cut to deal with the blowdown damage. Plus there were many pole sized (6 to 8 inch) Red Oaks scheduled to be cut that were 60 feet tall just like the rest of the trees.

So when I saw this even/uneven age term, I wondered how this applied to this job.

[WDH]

I'm told that release is viable only to a certain age.  Pine that has been "Stunted" will not respond to release after a few years. (not my statement)

Slash pine is notorious for stagnating if left too dense as an even-aged stand.  The response after thinning of a stagnated stand is slow, so the site is not producing its potential.  Loblolly is more shade intolerant than slash and tends to resist stagnation by developing dominant and co-dominant trees.  That makes it easier to thin Loblolly and leave trees with enough dominant vigor to be suitable crop trees.

With the sometimes exception of stagnated slash, "stunted" trees will release, however, it make quite a few years for the tree to build up enough crown area to be a decent grower.  Therefore, better to leave trees that already have decent crowns to respond to a release instead of investing addition years in a "stunter" to get the crown needed for reasonable growth.

Leaves/needles grow wood.  Pine management is in many respects crown management to optimize stand growth.  The same can be said of hardwood as it relates to maintaining good healthy crowns.

[SwampDonkey]

Well Gary, uneven-aged management gets you more entries into your stands, usually more species diversity, generally deals with longer lived species, less productive per machine hour,  yields more volume per acre in a comparable time frame as even-aged (say 80 years). I've seen long term experiments indicating as much as twice the volume off uneven-aged managed tracts.

Even-aged management is easier to implement: with fewer species, with those species which respond similarly to disturbance, and with species with similar shade tolerance or longevity. One - three entries per cycle (80 year time horizon). Usually there is less than half a dozen species of any significant volume your dealing with. In my area it usually involves aspen, fir, white birch, red maple on mixed sites. Spruce to a lesser degree unless it's planted, then it becomes about 80 % of the species being managed on that tract. On hardwood sites we are talking mainly sugar maple, and yellow birch and maybe ash and red spruce to a much lesser degree as they are less than 10 % of the volume. Beech isn't really managed for because of disease. Well, managed to try and be rid of it I suppose. Most of our hardwood tracts are managed as even-aged, we are still experimenting I think. For the majority of hardwood tracts the quality isn't there or at risk of being reduced because of weather conditions and wildlife. Let loose some bull moose in a stand of pole stage maple and yellow birch. 

So, I would hope we choose which ever is appropriate. Sometimes you scratch your head over it. 

What was your question again? 

[Gary_C]

What was your question again? 

     Good question.

What do you do differently in un even aged management from even aged?  In other words, how could I look back on that two step shelterwood job and see that one or the other of these management techniques were used?

[SwampDonkey]

Someone has you a bit confused with their silviculture, or maybe I'm not following along to good. Shelterwood, seed tree, and clear cuts get you the same results, even-aged tracts of forests.

Shelterwood: leave good seed producing trees that eventually get harvested after 2-3  entries when the regen is established. These trees are left to shelter the new regen from direct light and reduce invasive species establishment. Not every tree will be a good tree simply because of site quality and availability of nice ones to leave. Not all sites are uniform in their distribution in other words. Usually 10 years or so between entries.

Seed tree: Leave behind good seed trees to establish the next crop and come back the next time to remove the seed trees. Usually less than 20 years for the final entry, generally around 10.

clear cut: most every tree is taken now and the next crop is either established already, will be planted or is copiously established following the harvest.

Uneven-aged tracts have usually more then 3 age classes, 20 years or more between them and involve group selection and single tree selection to encourage a new generation every 20 years and maintains a wide spread of age classes of trees at different development stages.

A select cut is usually a term substituted to cover up that ugly term high-grading. Cut what you want and leave the rest. Take her from there.

[SwampDonkey]

flatrock, from what I read in your last post, you have a pretty good handle on the situation on your woodlot. Probably a better handle than a good many woodlot owners. I do believe the Ontario marking guide that Geoff mentioned would be a worth while read. I have a copy I downloaded some time ago. I think if you Google the Ontario Woodlot Owner Association you can find a link. You already understand that an inventory will go a long way in your planning process. Your on the right path. Ask your local forester for some more guidance. Don't expect anything for nothing and don't get too discouraged with the answers you get from the forum. Just ask yourself if the information you got was well worth what you paid the source for it.

It sure would be nice if more woodlot owners in my area had the outlook you have on your land instead of going to logging contractors first, then coming to Woodlot Owner Associations, foresters and technicians to fix what's left behind. 

[Ron Wenrich]

One of the hardest things to do on any forum is to answer questions with specific answers.  Often the questions are vague, and you don't know exactly what the conditions are.  Are you dealing with a small woodlot or a large timber tract?  You have no idea of what's on the ground.

In the past, I've done a lot of thinnings, just like SD has described.  We did a lot of work trying to convert the stands from an even aged to uneven aged.  We did it as both procurement foresters and consulting foresters.  I found that the forester has certain philosophies of management that transcends the position. 

But, you have to let the stand tell you where you are going to put in an opening, which trees are going to be left and which trees should be taken.  Its not cut and dried.  It can't be taught in a book.  All foresters practice some sort of diameter limit cutting.  I used 26" as the upper diameter limit.  That has fallen pretty hard back to 18".  It has to do with merchantibility of the residual stand.  I've also seen writings where 18" is supposedly where you get the best economic return.  Its not necessarily the point that grows the highest amount of good quality fiber (personal observation).

Uneven aged management is a lofty goal on private lands.  I have seen it fail more times than it has been successful.  The largest problem is that the forest is longer lived than the owners.  Land ownership changes pretty often in this country.  Rarely do you see ownership last longer than a few generations.  Even if it does, the thinking keeps on changing.  More than once did I see a potential landowner sit back and wait until he was the owner of a tract of land.  Then, it was cleared to make more lines in the bank book.

Practicing in the field is just as problematic.  Its doubtful that a forester would be able to do much in just one thinning.  It is also doubtful if they are around for thinning #2 or #3.   I had one consultant come up to me and brag about doing work for a client I once had.  We did the uneven aged management thing.  The conversation ended when I asked him what was left.  He said he got it all.  So, my work went out the window as the landowner was smoozed into thinking that the trees were mature and needed to go.

The other problems you get into is in harvesting.  Those openings you make in the forest are really good spots to throw trees during the next harvest.  Its also makes for some fairly unencumbered skidding, being that its just saplings.  I remember doing some cutting for a guy and I was fairly proud of being able to cut around a nice small tulip poplar.  It had good height and was ready to grow.  The skidder driver hit it square when he came up for the next turn.  For uneven aged management to work, the loggers must be on the same page.  Residual damage can be pretty high in these stands.

[SwampDonkey]

What Ron said. 

[tonich]

Ron,
Would you please tell me, if you can recall a hardwood stand, from mentioned above:
For which tree species worked upper diameter limit?
What was the approximate composition before and after turning to uneven age forest?
How much time did take the introduction to uneven age stand?
What were the criteria for uneven age stand in particular (were the tree distribution by age, diameter, height etc?)?

Thanks! 

[WDH]

Uneven aged management is a lofty goal on private lands.  I have seen it fail more times than it has been successful.  The largest problem is that the forest is longer lived than the owners.  Land ownership changes pretty often in this country.  Rarely do you see ownership last longer than a few generations.  Even if it does, the thinking keeps on changing.  More than once did I see a potential landowner sit back and wait until he was the owner of a tract of land.  Then, it was cleared to make more lines in the bank book.

This is a very astute point made by Ron.  Unevenaged management can be a romantic notion unless you are thinking and behaving in terms of decades or even a century or two.  Nature does it, but nature has unlimited time.  In the old growth forests where nature did it, the maturity of the cycle was in centuries, not a couple of thinnings. 

A forester or landowner cannot expect to bring this process to fruition, especially in hardwood management, in the course of their timeframe.  However, what you can do is start the process.  You can create different mini-stands.  You can create openings for regeneration.  You can select for crop trees.  You can improve the stand composition and vigor with harvest.  Then, you have to persevere for several generations. 

When I see hardwood stands, my first management thought is, "How can this stand be improved to produce more value?".  Rarely is a clearcut the way to increase stand value.  What really disappoints me is when hardwood stands are harvested and the 10" to 12" trees of the desired species are cut for pulpwood at very low stumpage value.  Those trees just spent 20 - 30 years to be on the verge of becoming sawlogs, and they are taken down.  Now, you have to wait 20 - 30 more years to get to the same place.  That is what a clearcut can do for you unless the whole stand is a high-graded piece of junk.

That said, I am no Hardwood Silviculturist.  I always enjoy the discussions on hardwood management because I always learn something more.  Makes me want to go work in my hardwood stands .

[beenthere]

Ron
Very well said, from many standpoints...be it landowner, logger, or the third party advice-giver/planner.

I've had my woods under "my" management plan for 40 years now, and have enjoyed working with the thinning of old, mature low-quality trees left by a white oak stave cut some 50 years ago. Because the white ash were so prolific, and I like ash, I managed the stand in favor of ash, along with walnut, white and red oak and hickory if it was there. Now, the looming EAB problem leaves me in a dilema, as to what to do with the ash.  I'm thinking removing the 4-10" dbh ash trees for firewood, and leaving the remaining ash to hopefully last long enough for sawtimber. The smaller ash to hopefully survive the EAB predictions.

Managing a forest seems similar to a teacher in school having a new set of pupils each year, and trying to adapt to their needs and feed them knowledge..not knowing how they will fare after they move on from this point in their life (just that the teacher can't remove the bad actors as easy as the forester can weed them out  ).

[Ron Wenrich]

Tonich

The upper limits that we used 26" on was for good sites and for red and white oak, ash and tulip poplar.  Those were in good supply on most good sites.  If there were any white pine or walnut, we would include that for the upper limits.  Species is very area specific.  As site decreases, upper dbh limits get lower.

In my opinion, the upper limits can be higher if tree quality merits it.  Just because you hit a certain size doesn't mean the tree has reached a point where it is getting less valuable.  We had one job where our red oak averaged 36" and we left 28" trees for stocking.

Since you are planning on coming back onto the area in 15-20 years, residual stocking is pretty important.  Cut too much an you'll have epicormic branching and that effects lumber quality.  I see it when I'm running the head rig.  I can tell stands that have been skinned at a previous time.  We would try to leave a residual stand of 70 BA, with higher stocking in stands like white pine or tulip poplar.  Our goal was to leave crop trees and open up their crowns.

Most of the stands I worked in had been high graded in the past in some form, and our goal was to convert to uneven aged management.  The first trees to go were the obvious over mature stuff.  This was usually red oak, since in prior years, red oak wasn't worth much and was left behind.  Wolf trees of poor quality or species was marked to be girdled and left as den trees.

The next step was to make a hole to drop the big trees, especially if there were other good trees that we were going to keep.  We would find an area where there were trees of the poorest quality.  Species wasn't that important.  A good maple would be kept rather than a poor oak.  These were the areas we were hoping for regeneration and quite often got it in tulip poplar or ash, if not oak.

If we found an area that had a bunch of poor quality stuff, we just made a mini clearcut.  The stand told us where to put in a hole for our regeneration.  We didn't try to map out anything, as that is a waste of time.  We rarely had the luxury of an inventory.  Our inventory was taken on the spot using a prism or angle gauge. 

We weren't out to get new growth in every corner of the woodlot.  Just in those areas where the current forest was no longer a good one to take forward for another 15 years.  The next time around, we hoped we could find other areas to introduce new growth.  So, it would take a long time until you covered the whole area.

Out of all the jobs that we did, I can only think of one that has survived the next generation of foresters.  Some were logged again within 10 years.  One was highgraded within weeks after the job.  All those 16-24" trees we left were put on a truck and moved down the road.  The only thing left were 12-14" trees. 

I've been on some of those heavily logged stands.  Most come back in weeds and vines.  One guy asked me how long to expect his next forest to come back after a real heavy logging.  I told him not in his lifetime.  Its been 15 years and I'm starting to see a few trees.  Mostly it came back in goldenrod and multiflora rose.  Even the residual stand died.

[tonich]

Out of all the jobs that we did, I can only think of one that has survived the next generation of foresters.  Some were logged again within 10 years.  One was highgraded within weeks after the job.  All those 16-24" trees we left were put on a truck and moved down the road.  The only thing left were 12-14" trees. 

I've been on some of those heavily logged stands.  Most come back in weeds and vines.  One guy asked me how long to expect his next forest to come back after a real heavy logging.  I told him not in his lifetime.  Its been 15 years and I'm starting to see a few trees.  Mostly it came back in goldenrod and multiflora rose.  Even the residual stand died.

What a huge disappointment, isn’t it!?
All efforts and knowledge applied, went down the road. At the drop of a hat.
Pity, they must have been the best possible forester’s intentions…

Ron,
Thank you for your detailed replay!
Thank you for being so dedicated!
I do hope, you have some good followers down there.

Toni