How much ?¿

[jim king]

Is there a standard percentage that should be cut out of a mature forest in order to maximize production and maintain forest quality.
We have an average stand of 35,000 BF per acre and an average tree matures in 50 years.
I am currently cutting about 4000 bf per acre with no skidders and will clean again in about 5 years but much less volume.
How does this stack up vs logging in the North ?¿

[Texas Ranger]

Jim, not enough information here, for a forester not from the area.  Stand condition, species, soils type, even local economy, can influence all you ask.  Cutting your annual growth every 3-5 years may be a start.

[jim king]

Here is a start.  The forest is virgen and very healthy but also mature and the loss yearly due to trees falling nuaturally is probably in excess of what we can harvest.  We only work with 17 species and there are on every acre about 150 .  Soils are generally clay.  The local economy is a disaster but the land is several miles from a road so we have no poaching.

[Ron Scott]

Jim,

It will depend upon the tree diameters, height, and density of the stand and if you are doing a "true selection" harvest. Our northern hardwood selection harvests run 1500 MBF/acre to 5,000 MBF/acre sawlogs and 200 cords to 300 cords/acre pulpwood removal. The pulpwood includes topwood. 1,500 MBF /acre is usually the low end for a commercial sawlog harvest.

This is thinning to a 70-90 square feet basal area.

What do you mean by "no skidders"??

[jim king]

What I meant by no skidders is that we carry the wood out on the backs of people so we dont have collateral damage .

[crtreedude]

Sounds interesting Jim. We tend to use Oxen to get the wood out - if we can.

[jim king]

Here is a copy of a preliminary study done on our methods.  I would like to know how this compares in a general way with forestry methods in the States.  Sorry I could not load the photos with the script of the report.

Low Impact Logging Methods in Peru
Observations from 7-25-07 to 7-31-07

Donald Harby
Technical Consultant
8-2-07

Introduction
   The method of using chainsaws as a means of low impact logging was observed on one logging site near Iquitos, Peru.  The overall impact on the site and the comparison to conventional logging methods are addressed.  Then recommendations for future work and research is included.
   The site is 40 hectares located about 2 miles off of the Iquitos-Nauta highway at the 48km marker.  The low impact logging effort has been in operation for about 8 months and approximately 100,000 bft of lumber has been processes and another 40,000 bft of cants have been removed from the site and wait final processing.

Comparison to Conventional Logging Methods   
   This site is impractical for conventional logging techniques.  The first problem is the access road.  It is approximately 2 miles long and crosses at least 4 large year-round flowing streams (figure 1).  It also crosses several low wetland areas.  It has one area with that has an estimated slope of at least 45 degrees for over 300 feet.  The amount of engineering, bridge building, and soil moving to build proper logging roads would be enormous.  The second problem would be logging roads on the property.  The property has several year-round streams and many low wetlands and swamp areas (figure 2).  It was estimated that the slope in many areas to be between 45 to 60 degrees with elevation changes between 100 to 200 feet common.  Given the topography and the amount of streams and wetlands a conservative estimate of 10-20 percent of the total forest would be lost if roads were constructed in a manner that conventional cable skidding equipment could reach all of the trees.   
 

Figure 1.

   However very little damage to the forest exist from the foot trails that are used in the method of cutting the cants on site with chainsaws.  In fact it is very difficult to find and travel on some of the foot trails after only a few weeks of nonuse. 

Forest Regeneration
   One of the most obvious effects of sawing the cants in place in the forest is the sawdust that is left behind.  It is also well known that using a chainsaw for sawing cants is very inefficient.  A large percent of the lumber is wasted into sawdust.   On this site approximately 6 inches of sawdust was left in the area where the cants were cut
Figure 3).
 

Figure 2.

 
Figure 3.

   One of the most unexpected finds on the site is the re-growth of the trees in the sawdust.  Normally because of the microbial action there is an initial nitrogen shortage in the soil that is covered by sawdust.  But on this site there seems to be a very fast re-growth (figure 4).  Compared to place on the site that was slashed and burn at approximately the same time (about 8 months) there is almost no growth (figure 5).

 
Figure 4.
 
Figure 5.


Tree Growth Rates and Age
   Many speculate on the age of the trees and the growth rate of the trees in the rain forest.  Very little data is available for the types of trees on this site and in Peru in general.  On this site no very large trees (over 48” DBH) were observed and no evidence of large trees (stumps or blown down trees) were observed.  After personally interviewing many local people who work or live in the forest it was estimated that the mature trees were approximately 50 years old.  It is also estimated that the growth rate and size has a lot of variations on this site. 

Conclusions and Recommendations
     The impact from harvesting over 140000 bdf of lumber from this 40 hectares site is almost undetectable.  Based on the observed topography, types of trees, access, and streams and wetlands the only practical way to harvest the lumber from this site is to process the logs into cants on site.  Then carry the cants to the road by hand.
   Based on the size of the trees, estimated growth rates, and the logging methods a system of continuous harvest could be developed.  One of the major obstacles to overcome is the perception that a forest site needs to be harvested in cycles.  Like a plantation on maybe a 15 or 30 year cycle.  This perception seems to be very strong with the people of Peru.   But on this site it take a couple of men at least a week or two to cut an average size log into cants and then carry the cants to the road.  A crew or 2 or 3 men could harvest approximately 25-30 trees a year.  At that rate they would not keep up with the growth on the 40 hectares and a continuous logging process could be sustained.
   Very little research has ever been done on these species of trees or logging methods in Peru.  This site is perfect to start a long-term research study of low-impact logging in the Peruvian rainforest.  Its location, access, and the fact some important work has already started make it perfect.  However, there are many topics that need to be studied, some long-term, in order determine the best practices for the area.  The following are recommendations for future research and development of the low-impact methods of harvesting the timber in the Peruvian rainforest.
•   Educate the locals that are working in the forest on tree identification and how the forest regenerates.  For example, they chopped down every small tree they can while walking on the paths.  They do this mostly out of habit and because the trails would grow shut if they didn’t.  Possibly many valuable species that are re-growing are destroyed.
•   Start a thorough scientific literature search on tree growth models and rates.  I started a search for literature and found there is very little research that has been conducted in Peru.  There may be more from other countries that are close to the same latitude with the same type of species.  This is critical in helping to determine the rate at which trees can be removed.
•   Start a long-term study on the growth of the trees on this site.  We have already identified several trees of each species.  The DBH will be measured periodically until the trees are ready to harvest.  This is also critical in helping to determine the rate at which trees can be removed.  This is also groundbreaking research because most of these tree species are considered firewood or charcoal wood to the people of Peru.  But a larger more detailed study is needed.   
•   Start a study to determine why the re-growth is so good in the sawdust.  A study of soil samples may help determine the cause.  The fact that many species in the area are nitrogen-fixing trees may help explain.  This is also critical to the project.  For example, maybe portable sawmills should be used in the forest to increase the amount of sawdust.  Or maybe the re-growth trees should be selected based on if they are a nitrogen-fixing species.
•   Start to educate the locals about continuous harvest methods not clear cutting and periodical cycles.  The value of the wood is high enough they should think about managing individual trees not plantations.  This may be the most difficult, but educate them on long-term not short-term profits.
•   Start an economic impact study of the low-impact logging methods.  Widespread adoption of this method would have a huge impact on the people of the area.  The increase in income over charcoal or fishing would be at least several times greater. 
•   Develop a partnership between researchers in Peru and the USA.  Research collaboration between universities in Peru and the USA will be critical for the long-term success.  If a good relationship is developed it will be easy to secure research funding from government agencies.  Without funding and government support it will be difficult to prove these are the best logging practices for the area.


Biographical Sketch - Donald Harby
      Donald Harby has a B.S. Degree from St. Louis University, a M.S. in Biological/Agricultural Engineering from the University of Missouri – Columbia, and PhD in Mechanical Engineering from the University of Missouri - Columbia.  He worked for the University of Missouri – Columbia as an electrical engineering technician from 1993-1995.  He worked as a design engineer for Battenfeld Technologies, Inc. in Columbia, MO from 1995-1999.   He was hired as an instructor at Linn State Technical College in Mexico, MO in 1999.  He was then was hired as an assistant professor and program coordinator for all engineering technology programs at Central Missouri State University at Warrensburg, MO in 2006
   He has over 15 years experience in machine design related to the wood processing industry.  Including logging and logging equipment, automation, PLCs, electric motors and controls, CNC, machine tools, electronics, computer interfacing, lasers, and photonics.   His current research interests include logging and wood processing equipment design and optimization.

[Ianab]

Harvesting NZ native forest is basically done on the theory that you remove the same amount of wood each year as is grown by your target crop trees. You would work this out by measuring the growth of sample trees to work out how increase you actually had.
So roughly if you have an average max of 50 year old trees you should be removing 2% of the standing wood per year. (10% every 5yrs or 20% every 10 etc) Different species, different time frames as well, even in the same forest. You may have some species with a 1% growth, another with 3% ?

What you may in fact find though, is that your growth rates improve as you remove the old 'stagnated' trees and the forest is made up of younger more vigourous specimans. By monitoring the growth rates of your replacement trees you can judge this. Maybe with the more open growing conditions you can get trees to harvest in 30-40 years?

I notice in your report the author makes mention of this and also doing more management of the forest. Selecting your replacement trees, possible removing non-desirable species to make room for more usefull varieties.  Have you done any study into the re-generation of the specific species? In our forests some species will only regenerate under the shelter of other trees. So they grow in the 'light tunnels' where a single tree has fallen. If you clear cut, those species dont regrow untill the 2nd or 3rd generation when the shelter and shade is present again.  Other species need full light for the seedlings to grow, if you remove a single tree you just get the shade tollerant species growing back.

So even selective harvesting can radically change the composition of the forest over the long term. Potentially you can be harvesting one species, but re-growing a totally different one. Or you can create a better environment for the species you want and improve the future harvests.

These things have been studied fairly well with our local trees, but I guess you are pretty much on your own with the trees you have  I'm guessing it's hard to knows a trees age there as growth rings may not even be an accurate measure?

Best thing you can probably do is get some measurements and tags on a few of the trees you skip this harvest, then measure them each year untill the next harvest in 5 years. That will give you some real data on the growth rates.

Cheers

Ian

[jim king]

Ianab:  What you have described is exactly what we are starting to do as to the volumes and the natural regeneration of species seem to indicate this is the formula.
We are marking and measuring species trying to determine growth rates.  The rings here are not seasonal growth rings as you have said.  They are a history of the many crisis that the tree has gone thru such as floods, droughts , disease etc..

One thing I have no answer for.  When a tree falls down naturally which we guess is about 2% anually what is the species that replaces it.  Is the tropical forest continuously evolving or does it have a plan.  My guess is that it is continuously evolving and even creating new species.

You are very correct in assuming that we have very little data or backgroud information to draw from concerning the Amazon and how to manage it. 

The newest theory that has everyone confused is that the Amazon due to all the rotting vegetation due to all the mature and falling forest is actually a CO2 producer contrary to the last popular theme that the Amazon is the lungs of the world.   Personally I dont beleive in either theory but they are fun to watch in their continuous revolving state.

[Ianab]

The newest theory that has everyone confused is that the Amazon due to all the rotting vegetation due to all the mature and falling forest is actually a CO2 producer contrary to the last popular theme that the Amazon is the lungs of the world.   Personally I dont beleive in either theory but they are fun to watch in their continuous revolving state.

I think a mature untouched forest should be pretty much carbon neutral. The amount of carbon in it doesn't change. It just cycles around through the growth and decay. Unless it's getting sunk into a peat swamp or something and taken out of the cycle for  longterm storage.

Actually milling some of the wood and making it into furniture does the same thing, as long as it stays as wood, it is carbon removed from the ecosystem.

Save the planet .. cut down more trees 

Cheers

Ian

[WDH]

My thoughts were in the same vein as Ianab's.  You have to be careful not to high-grade the desireable species and end up with less desireable shade tolerant species that will take over the site as a result of your activities.

[Ron Wenrich]

I think you asked this question before.  My biggest concern is that you have over 100 species, but you only cut 17.  If you want to keep the system balanced, then you can cut your annual growth and theoretically have a balanced system.  However, mortality would have to play a factor and come out of your annual growth account.

I don't know how quickly things heal over after your cut, but it would be helpful if you would go back to a spot 3 months, 6 months and a year to see what types of trees have come in after you have done a cut.  That can give you a good idea if what you're doing is beneficial or if its changing the forest.

Up here in PA, we used to have large stands of hemlock and white pine.  They went in and cut it all down, and now most of the stands have reverted to hardwoods.  That has changed as we went from a wood based heating system to that of oil.  Coal has replaced wood at the industrial level and in some homes.  That meant that all those off species that used to go into the stove have been left to grow.

Then came the theory that if we take out the mature trees, the small trees will take over.  Unfortunately, the small trees were as old as the large trees and don't respond as well to release.   And, due to the types of cutting, we are seeing a different type of forest take over.  We are going from an oak dominated forest to a red maple dominated forest.  Not necessarily a good thing.

So, finding out how your successions are going should help determine what is allowable and what is recommended.   You're starting at point A.  What you do can take you to several other points (B,C,D,...).  Its hard to start at point A and stay at point A.

[WDH]

I don't think it is possible to stay at point A with 100 species, each trying to gain a foothold.

[Geoff Kegerreis]

Is there a standard percentage that should be cut out of a mature forest in order to maximize production and maintain forest quality.
We have an average stand of 35,000 BF per acre and an average tree matures in 50 years.
I am currently cutting about 4000 bf per acre with no skidders and will clean again in about 5 years but much less volume.
How does this stack up vs logging in the North ?¿

It does not "stack up", as you can imagine.  The sites down there are not even in the same category as the sites up here.  I would be surprised to learn that you are only dealing with 17 species on any given acre in Peru.  Maybe these are the species which are commercially desirable on the current market? 

No doubt part of the problem is the lack of growth rings - non-existent to the naked eye due to a lack of seasonal temperature differences.  This may be addressed microscopically - but unsure as of yet.

It's a good start - but much of the Ecological information that is necessary is not addressed at the bottom of the page.  I think on-site production of wood products is a very good idea for that site - as is not using skidders (results in less compaction).  Study the Ecological processes more in depth and increase the efficiency of the wood production (based on the silviculture and other missing Ecological information), and I think you'll be on to something significant.

I have all kinds of ideas, and if you would like to discuss this further, please send me an e-mail directly to geoff@timberlineforestry.com.

Regards,
Geoff

[Jeff]

Generally, we like to see the conversations continued here Geoff, where all can benefit.

[Geoff Kegerreis]

Generally, we like to see the conversations continued here Geoff, where all can benefit.

I'll sum it up this way: SIGNIFICANT management efforts should be put forth on those sites BEFORE the logging happens.  Otherwise, not only will an action have been done that may cause irreversible harm to the forest (and the commercial viability of it), but growth rates of desirable species could decrease and possibly even stop completely.

Sure, the logging looks low-impact.  The site-based forest product manufacturing may be a better idea than other methods - but what are the consequences of those actions?  Can an outcome even be forecasted with any reasonable amount of probability?

We aren't talking about an "A/B/C" line here folks, this is WAY more complex than those kinds of charts suggest (actually optimal growth in any uneven aged hardwood stand is seldom achieved with those charts anyway - those charts are only a guideline).

Tropical forests with native vegetation can be managed appropriately, but it's very complex and involves algorithmic based multi variable matrices along with linear programming which are FAR beyond the scope of discussion on this forum (hence the suggestion for off-forum discussion). 

In those forests, there are so many potential commercial products that a complete inventory should be done at all levels of the canopy.  Otherwise, the landowner has no idea what kind of a value log extraction is relative to other potential products which could be present on the tract - and potentially, we all could lose.  We are losing every day due to the destruction of species in the tropical forests that have a potential to develop alternative forest products (pharmaceuticals for example) because folks are out extracting logs (among other activities) which are not appropriately planned. 

Think about this for a moment: If it's only about the money, what do you think is worth more?  Pharmaceuticals or exotic logs?  Hind sight is 20/20. 

Inventory the species on the tract first.  Contact others on what Ecological and Silvicultural research has been done in Peruvian forests.  I know there has been extensive research on those forests and the growth rate of specific species.  There are plenty of ways to fill in the blanks: Researchers are just awaiting the calls for new ideas to set their grad students loose on.

Maybe the research has already been done on the tract, but I've yet to see anything posted regarding it.  Based on what we've been presented here, it looks like logging is being presented as forestry, in which case couldn't be further from the truth.

The management of the most complex forests in the Eastern North America (Central deciduous forests) have been similarly studied throughout the years by Federal and state agencies, Universities, commercial firms and individuals which is why we have the knowledge we do about the management of our forests here.  Unfortunately, 85+% of our forests are still mismanaged due to landowner ignorance...and the saga continues.

Forest management continues to be a dynamic field.  Significant discoveries are made annually that affect the health of the forests.  One thing is certain however, and that is the more intensively a forest is managed, the broader the possibilities for production become.

[Gary_C]

Geoff

A very well stated scientific point of view. However there is a more predominant point of view that we should "just do it" and let the scientists figure out what we did wrong later. After all, how are they going to study the effects if nothing has been done?

Think about this for a moment: If it's only about the money, what do you think is worth more?  Pharmaceuticals or exotic logs?  Hind sight is 20/20. 

I'll take the exotic logs!  In my opinion the average person in this country is over medicated and under worked and would benefit from some manual labor carying some logs.   

[jim king]

A bit late in answering but here we go.  We work with 17 species as they are what sell the best for us.  All of these species were traditionally used for fire wood.  We are a specialty wood company and coloured woods and figured woods are what make us go.
We have no interest in Mahogany, Spanish Cedar and the standard woods for export or the traditional construction woods used locally.  I think it will be OK if I put my website here as we doe not use it for sales so you can see the types of wood we use.  www.exoticwoodworld.com     

Each 90 acre plot is inventoried and a management plan is registered with the DNR here prior to cutting anything.  We do have hundreds of species and the problem is always what do you do with the trees that are of bad quality or simply ugly and not .   It does not seem reasonable to just cut them down to rot and say we have a balanced thinning. One thing we do is to leave what we call the mother trees for natural reseeding.

Contrary to what anyone says there is not a bank of information available on the Amazon as one might think.  What information there is , is not dependable and very limited.   A good example is that the WWF wrote the forestry law for Peru paid for by the US Government and it would be the biggest disaster and deforestation program in the history of tropical forestry if anyone paid attention to it.  Very interesting that the American taxpayers donated 10.6 million USD to the WWF to make the law.
http://www.panda.org/about_wwf/where_we_work/latin_america_and_caribbean/country/peru/our_work/forests/index.cfm
This law was obviously written by New York and European experts who have never set foot in a jungle.

As mentioned there is no data base on what will regrow from a thinning or select harvest area.  About the only thing we know for sure is that Balsa Wood is the first species to take over destroyed cocaine plantations and the next generation growing under the balsa is again hardwoods.  The wide variety of species is a definite problem and plantations have been tried unsuccessfully on a limited basis.

I keep asking questions as I am not a forester nor have I met one who knows much about tropical forestry.  The input from everyone is very valuable.  We do have a chain of custody that is probably stricter than the majority of states in the US.

I will attach it here.


CHAIN OF CUSTODY OF WOOD FROM PERUS FOREST TO MARKET

The forestry law in Peru was designed and paid for by the WWF and the US Agency for International Development.
Below listed are the steps required to harvest and export wood from Peru.
1: The first step is to purchase a piece of land to log or bid on a government owned forestry concession.
2: In order to cut timber you need a forestry logging permit in the case of land ownership or a license in case of a rented concession.
3: Once you have a forestry permit or a license it is required      that you have a licensed forester inventory the land in question and make a detailed logging and work plan.

4:  This Plan/Proposal is submitted to the Department of Natural Resources of Peru for modification and approval leading to an on site inspection.  Registration of all chainsaws is required with the Dept. Of Natural Resources.

5:  The next phase of the approval is an on site inspection of the property to be logged by the Dept. Of Natural Resources foresters and technicians verifying what trees are to be cut and how much per acre.  This includes the local name of the tree plus scientific identification.

7:  After the inspection the management plan is submitted to the Dept. of Natural Resources for approval.

8:  If approved the property plans are sent to the titling office in Lima for verification of the coordinates.

9:  If the six month process above is approved the owner of the permit can start harvesting the trees marked for removal.

10:  Once the logs are ready for transfer to Iquitos from the jungle an inspection by the Department of Natural Resources is required to verify that the wood came from the land designated.

11:  Each piece of wood is painted with the number of the logging license in the presence of the Department of Natural Resources official and scaled and inventoried prior to movement and forestry taxes are paid also prior to movement.

12:  With the signed inventory a permit is requested to move the wood to the factory for processing and the police are notified of the pending transport for the police inspection.

13:  Once the wood has reached an authorized factory with Department of Natural Resources approval it can be cut.

14:  For removal of the wood from the factory for kiln drying a transport permit is requires for movement.

15:  Once the wood is dry and a permit is obtained it can be moved to the processing facility.

16:  Once in the licensed processing facility and manufactured into a product a sanitary certificate is obtained after inspection by a division of the Health Dept stating that the wood is clean and free of any insects or other problems.

17:  When ready to export one more inspection is required by the Dept. of Natural Resources and police prior to obtaining the permit to move the wood to the port.

18:  With the above documents a Certificate of Origin is issued by the Chamber of Commerce authenticating the origin of the product.

19:  With all of the above starts the normal procedure of packing lists, bill of lading etc for Customs and the wood can be loaded on the ship.

20:  Once in a US port the next series of inspections starts and a year later the customer gets to buy a piece of wood.

If all of this seems a little out of hand just consider that Loreto State of Peru where we are located is 30% bigger than Oregon and produces .005% 0f what Oregon produces every year.  The entire Amazon which is as big as the continental US and includes many countries produces 2.4 times the production of Oregon.

[Tom]

Jim,
The problem is one of perspective.

To manage 17 species in a forest of 100+ species is only to manage the harvest.

If you are considering the "forest" for management, then you need to consider all 100+ species as well as the rest of Flora and fauna.

You can't ethically cut down tree "B" because it is interferring with Tree "A" without knowing what tree "B" is.  I know you are behind the curve when it comes to finding any knowledge about your forest.  It is not only not well known, but there are few people who are studying it.   Still, to be a steward of the forest, you have to consider "all" of species that live there, animal and plant alike.   Your perspective needs to be the entire forest, not just what is economically merchantable. 

You asked once, "what is a definition of a forester"?  A true forester is working with the entire ecosystem.  Removing specific, economically valuable trees is just a small part of his concerns.

If you are developing a plantation to put on destroyed Poppy fields, then you could manage for the 17 merchantable trees.  They would be the only species on the land that mattered.  To approach the natural forest with that same view is to have too small of a perspective.

An analogy we use for situations like this is, "Don't jump into the hole until you see how deep it is".

You could be managing against species that will be worth many times the money that the recognized 17 are worth today.

That doesn't mean that you can't still harvest trees, it just means that you have to look upon the operation with a larger scope than you are now.

[Ron Wenrich]

You have no interest in Mahogany, or Spanish Cedar, but how much of that makes up your forest?  You can't just disregard it and cut in your desirable species.

Up here, I have seen this cycle repeated over the years.  Loggers go in and cut the merchantible timber, and leave behind those of lesser or market value.  Those trees will then grow even better, since they have had their crowns thinned.  The landowner gets a shot of income, but depletes his resource. 

Quite often landowners are encouraged to do a non-commercial thinning.  That means they should go out and cut the junk from their stands.  This usually comes up due to poor managment practices in the past.  If you don't do it, you just continue the poor management practices. 

So, cutting some of those non-commercial trees and let them rot may be a viable alternative to letting them stand and clutter up your stand.  You may also want to cut the lesser valued trees that you have little use for and send them down the road or set up a secondary operation.