counting trees

[mountaineer]

has anyone ever counted and documented the trees on their property? i was thinking about taking 1 acre and counting all trees bigger than say- 6dbh. the reason i want to do this is to see the percentage of different species and size. do you think this would be too overwhelming?
i think it would also give me a better understanding of my property. ??? ???

[Jeff]

Onewithwood I do believe is in the midst of such a project

[Dodgy Loner]

I did it on 9 acres on my dad's property.  Measured every DBH larger than 4.5", measured the height of every tenth tree, and estimated the number of logs on everything that would make sawtimber or chip-n-saw.  Although the goal was to get an inventory for harvesting, I found several tree species on the place I didn't know existed.  It was pretty interesting, but time-consuming.  Took about 3 days.

[woodtroll]

Great idea. Count everything 2 inches and up. So you know what your stand will be. You should also watch your seedlings, see what they are and amounts.

Maybe mark specific trees to come back to over the years to see how they have grown.
It will take a bit of time but would be interesting.

[Mike_Barcaskey]

here's the species list from an Urban Tree Management Plan I did for a homeowners association. The initial count was over 1,600 trees, the largest tree inventory I have done to date. Every tree was classified as to size, condition and management needs. This is different than the Forestry Management Plans I write as these trees are managed for esthetics and increased property value and most are managed individually and a more diverse species population is desired.


Species               Count            Percentage


Acer (Maple)            394               21.4
Prunus (Cherry)            336               18.3
Fraxinus (Ash)            162                8.8
Quercus (Oak)            121                6.6
Robinia (Black Locust)         119                6.5
Tsuga (Hemlock)            74                4.0   
Crataegus (Hawthorne)         48                2.6
Thuja (Arborvitae)            45                2.4
Picea (Spruce)            41                2.2
Liquidambar (Sweetgum)      40                2.2
Pinus (Pine)               39                2.1
Malus (Apple)            34                1.8
Ailanthus (Ailanthus)         32                1.7   
Pyrus (Pear)               29                1.6
Betula (Birch)            24                1.3   
Sassafras (Sassafras)         21                1.1
Liriodendron (Tuliptree)         15                0.8
Cornus (Dogwood)         14                0.8
Rhamnus (Buckthorn)         9                0.5
Populus (Poplar)            8                0.4
Nyssa (Black Tupelo)         7                0.4
Magnolia (Magnolia)         7                0.4
Rhus (Sumac)            7                0.4
Lindera (Spicebush)         6                0.3
Juniperus (Juniper)            6                0.3
Morus (Mulberry)            6                0.3
Juglans (Walnut)            5                0.3
Fagus (Beech)            3                0.2
Taxus (Yew)            3                0.2
Carya (Hickory)            2                0.1
Aralia (Devil's Walking Stick)      1                0.1
Koelreuteria (Golden Rain Tree)   1                0.1
Silax (Willow)            1                   0.1
Gleditsia (Honeylocust)         1                0.1
Sorbus (Mountain Ash)         1                0.1   
Ilex (Holly)               1                0.1   



This page last updated September 2007

[mountaineer]

how many acres was that mike? thats a lot of maples and cherries. i wish i had that many of those two. mine will read something like this

tulip poplar-50%
beech-20%
birch-20%
all the rest- :'( :'( :'( 10%

[Mike_Barcaskey]

That was only about 12 acres. As a lot of small landscape trees had been recently planted everything was counted. here is the size distribution.
one big thing the Plan made apparent was to quit planting maples and ash


Tree Size Distribution
3 inches and under         321         17%
3 to 6 inches            374         20%
6 to 9 inches            447         24%
9 to 12 inches            311         18%
12 to 18 inches         288         15%
18 to 24 inches          88          5%
24 to 36+ inches          12          1%

[Mike_Barcaskey]

unfortunately most of those maples are Norway Maple, much of which was growing wild along the edge of common areas. I couldn't believe when I found out they were actually buying Norway Maple seedlings to plant in the landscape.

[mountaineer]

whats the easiest way to determine dbh? take circumference and divide by pi?

[beenthere]

You can do that, or buy a dbh tape. Has a hook on the end to stick to the bark.

Might find one at Bailey's (sponsor to the left).  Looked and see Bailey's combines their d. tape with log length tape. Expensive way to go, but gives more for the money.

Cheapest would be your plan...measure circumference, and divide by pi   

[clearcut]

A lot depends on how large your property is, how diverse it is, what you need the information for, and how accurate it needs to be.

If you measure all the trees on one acre - you get a great representation of that acre but not the property as a whole. If you spread that acre out into ten 1/10 acre plots ( a circle with a radius of 37.2') you get a better representation of the property as a whole. If you stratify the property, that is create a type map with forest stands that are very similar (age, size, species mix, history) and put plots into those types, you can reduce the variability within each type and achieve even greater accuracy for the property as a whole. Measuring enough plots within each type allows you to use statistics to assess how accurate those estimates are.

In other words you ramp up from simple and less accurate to complex but much more accurate.

The same is true for the tool used to measure diameters. A biltmore stick is simple and quick and sufficient for rough estimates of height and diameter. Calipers are quick but more accurate, and a diameter tape is slower but much more accurate.

Consider measuring heights, or a least a sample of heights while measuring diameters. Height with diameter helps you estimate volume. Tools for height include the biltmore stick which has a Meritt Hypsometer, an angle gauge, clinometer, or laser based height finder. Again simple to complex, less to more accurate.

While you are out there running about you may want information on tree growth, site quality, insect and disease activity, etc.

[OneWithWood]

I am taking a break from inventorying my trees as I type.  Here is what I have decided to do on my 100 acres.

I measure every tree greater than 6" dbh.  I use a diameter tape because it is more accurate than the biltmore stick and relatively quick and easy.
I log each tree by species, diameter, feet of useable bole, number of clear faces of the first log, and note any defects or other attributes.  I also take a GPS reading after every so many trees so I have a clear idea of where in the woods the tree is.  I am learning a lot about the composition of my woods, the growing capacity, species density, terrain, etc.  I may even find a few more morel sites  8)
By logging everything 6" and up I get a very good understanding of what is in the midstory.  This is important to me so I know what will remain after a tree is harvested and what the potential is for any given species to continue or dominate.  I also make note of cull trees and wildlife den trees.  Saplings are noted but mostly I see where the deer have munched just about anything they can get to.
My inventory is a slow process because at the same time I carry a spray bottle of Garlon 4 and Ax-it.  I spray every autumn olive, multi-flora rose, ailanthus, pauwlonia, Japanese or Asian Honeysuckle and any other invasive I come accross.  I have also declared war on beech saplings growing up under my good oaks.  I leave the beech on the northern slopes to compete with the maples but I do not want an understory under my oaks shading out any new growth that might survive the deer.

A serious depletion of the deer herd is planned for this fall.

[SwampDonkey]

I did it for 25 acres of my lot last fall, found density, basal area, and volume by species  for trees 6 foot tall and up. Did it for areas I treated with a brush saw. I have a full scale plan that inventories the whole lot,  drainage and prescriptions, but i did this inventory for something to follow to see how things respond to thinning on my ground. As I was snow shoeing yesterday I saw how the snow was hard on some seedlings this past winter, breaking tops off. There's still 2-3 feet of snow to melt away. Have not seen any moose tracks since before Christmas up there. They'll soon be back down form the popple ground.

HERE'S THE CRUISE

[woodtroll]

Onewithwood
It's great your are taking the time to learn and observe your forest so intimately. Observing what comes next is vitally important. I would be curious to know what your mid-story is.
Are you checking growth rates?  How are you doing on oak seedlings and saplings?
How are the invasive plants affecting your desirable regeneration? Do you have garlic mustard?

[mountaineer]

onewithwood, you talk about beech on the northslope. my entire property is northfacing. would that effect the new growth after the property was cut 50 yrs ago? could that be why there are so many tulip poplars and beech trees? also someone said that tulip poplars are a quick growing "pioneer species"

[SwampDonkey]

Beech are very shade tolerant, more so than maples even. Up here, if you cut beech firewood out of a beech-maple forest, the understory will be over run by beech within 10 years. Your tulip tree is shade intolerant and grows fast to obtain dominance for light. Aspect may play a role in successful regeneration of tulip tree, don't know personally.

[mountaineer]

what do you men by aspect?

[Riles]

A south facing slope gets more sunlight than a north facing one (the aspect). In theory, your yellow poplar should regenerate better on the southern slope. Lots of variables here, though.

[mountaineer]

i can't imagine them doing better anywhere. lots of poplars. i just went to the top of the hill and looked down the south slope. seems to be more oaks over there. (i'm not that great with i.d. without leaves.) also a few dead ones on ground. ;D ;D burn baby burn. they will certainly help out my woodshed of mostly poplar.

[scgargoyle]

I've thought about trying to survey my 7 acres. I like the idea of taking 1/10 acre samples. Mine is almost all north slope, with oaks dominating (both red and white). There are a good number of poplars (they're easy to spot in the early spring) and a small number of hickories, maples, and sweet gum. Interestingly, there is no evidence of any beech, although they are common in the area. I have a few Virginia pines, which are going to get the axe (OK, chainsaw). The biggest challenge for me will be identifying all the trees!

[SwampDonkey]

Yeah, and it's just as easy to use a plot radius with a rounded number like 30 or 40 feet. Just use a compass and tie a ribbon at each point on the compass (N, E, S, W) to define the plot perimeter.

Here's some discussions that might help. You could use forum volume tables or from your state agencies that relate volume growth to site index. If your only interested in sawlog volume, then I suppose it's not too critical to use site indexed volumes. You just have to determine the length of the sawlog in the standing tree. But up here we use the whole tree length so we use site indexed volume. Site determines tree height.

[WDH]

The biggest challenge for me will be identifying all the trees!

We are here to help you ;D.

[woodtroll]

Man, I go work in the field all day and check this board and don't know which comment to address. Too many.
SwampDonkey
That works well for even aged or very consistent woods. A mixed sized or mixed aged stand needs more information for accuracy.  There can be a lot of variability in a mixed hardwood forest.
I would measure the trees, dbh as accurate as you would like. For me it is closest inch though two inch size classes are fine. I would do merchantable height. This depends on your local markets. By me, that would mean saw logs. So two foot increments with a minimum of 8ft.  Pulp sticks are different.  Figure the volume for each tree. Thiswould be your base for a per acre amount.
For site index I would measure the total height and age that tree. I have come to be vary leery of growth/volume projections based on SI tables. They seem good for general guides. Like good site vs poor site. But volumes have been way off of what a stand can produce.  By me 200bdft/yr/ac is common on the tables but I have a hard time finding that in the woods.
If annual diameter growth can be determined it is a big help. It tells you age of the tree, growth rates and what to expect.

Aspect or direction your slope is facing. 
Oaks like the dryer slopes, they like the moist north east slopes too but do better than the others on the dry slopes. Tulip grows great on your cooler/moist sites and sheltered coves. They will regenerate great with disturbance and light.
Beach do well in the shade, where I am they are worthless so they get left. They can be quite old compared to the fast growing poplar. It is typical to find stands with very old beech and large tall (younger)poplar.
Like WDH says we are here to help. Just start observing your woods it is a never ending education. That's why I love forestry!
Last thought, what about using a 10 factor prism, variable plots?  Not good for thick young spruce but great for hardwoods.

[SwampDonkey]

My method works for even aged or uneven aged, doesn't matter. Your measuring diameter in a sample of each stand. Stands have to be differentiated and areas found. Your differentiating dominance of each tree in the sample and choosing volume tables based on site, you can't measure every tree unless your looking at a tiny parcel of land. Some people I find confuse basal area with volume and I've seen 38 m²/ha used for volume when the volume is actually 20 cords/acre, not 38. Makes a difference when your trees are immature and 40 feet tall versus mature and 80 feet tall even though both stands can have 38 m²/ha, one has 38 cords/acre and the other half that. ;D

If your standard volume tables based on site indexes for your state are way out of whack, then the sampling the tables were based on was not too reliable. I've cruised enough woods even aged and uneven aged to know it is very accurate on total merchantable volume. The volume harvested verifies it, right quick. Making calls on whether a tree is a sawlog, veneer or pulp while standing is an art and I've never seen consistent reliable attempts to do it. Trees looks great on the outside, but had 3/4 heart when cut off the stump, so your veneer log just became a piece of pulpwood. High value products can only be accurately scaled when cut and inspected on the yard. No one up here will buy veneer and logs on speculation. ;)

[woodtroll]

It is great to read about the differences in forestry and how it's done in different regions.