Thursday, June 24, 2021

Timber Inventory Basics, Gathering Information For Management

Here are some of the basics for figuring out what you have in your timber stands, so you can figure out what you need to do. Things you need are a map or aerial photo, a layout of how you will be arranging your plots, compass for navigation, plus your pacing skills, Biltmore Stick, diameter tape, and a prism and/or angle gauge. Spray your ankles to keep the chiggers off. A tick lifter may be needed, too.


Joel (@Stranded Tree) said...

Thanks for going through this, David. I have the video bookmarked so I can watch it again. There's so much I don't know and you've been a big help.
My estimation with the walnut plots was to count a row and multiply by the number of rows but this gives me a better way to look at things.

The derecho last year damaged several dozen walnuts and black cherry and my straight hackberry was hit by lightning.
Nature has a way to thin out naturally but it always seems that the best trees are the ones that get culled.

Thanks for the info and if you could get me what that program uses for its analysis, I might be able to code up something that will run on a newer machine. (No intention of violating any copyright laws, of course.)

David aka True Blue Sam said...

Hi Joel! When working with young trees, plots by row or 1/10 acre plots work well. If you use an angle gauge or prism you will want a 5 factor for those small diameters, and then you need paper work sheets or a computer program to process the results. Here is a writeup by one of the foresters I worked with, and I have included it with plans for many years. A CONCISE GUIDE TO PRUNING AND THINNING
By Dan Schmoker

During the early stages of growth, nurture as many trees as possible to produce specimens with desirable form – a single, straight stem with large branch angles and a balanced crown. Stunted and deformed trees should be coppiced and allowed to sprout a new stem. Target 150 well formed, well-spaced trees per acre after five to ten years of growth. While more trees per acre would provide more future alternatives, the cost of managing that many stems per acre may be too high to justify.
When the tree crowns begin to touch, begin selecting the best trees (crop trees) based on form and crown. These trees should be released on at least three sides by eliminating those trees whose crowns touch the crop trees. In addition, prune as described in next paragraph and remove any vines. Stunted and deformed trees should be removed. If the trees were initially planted far apart, then wait for thirty feet of growth, then identify the best trees based on form and height (crop trees) and thin out any non-crop trees that compete with crop tree crowns.

Since pruning can be a labor-intensive activity, your pruning should be prioritized so that your costs are held down and you have time to fulfill the rest of your management objectives. There are four aspects to pruning trees and some are much more important than others.
The most important aspect to pruning is to maintain a single, relatively straight leader as high as you can. Do this by removing any branches, which may compete with the leader. It is not necessary to cut the branch off completely; just remove the last six to eighteen inches. This should always be the first pruning that you are concerned with, and may be the only pruning that you do.
Next most important for those trees with veneer quality potential is the pruning of lateral limbs before they get too big. Start lateral branch pruning as your trees approach four inches in diameter and prune lateral limbs before they reach one inch in diameter at the branch collar. Proper lateral branch pruning involves three cuts to prevent stripping of the bark, especially on long or large branches with a lot of weight. The first cut undercuts the branch about two inches from the collar; the second cut, just outside the first cut, removes the branch; the third cut removes the remaining stub at the branch collar.
Now look for smaller branches with tight angles to the main stem (less than thirty degrees). Remove these before they get larger. Large branches with tight angles may weaken and break in a windstorm or ice storm and greatly reduce the value of the tree. Eliminating these branches early removes that risk.
Finally, if you have the time, remove dead limbs and lower limbs, while being careful not to damage the branch collar.
Never prune away more than one-third of the live crown. Always leave a crown height at least half the height of the tree.