Forestry Functions. Using Excel to Produce a Stocking Table. By David R. Larsen, March 14, Objectives:

Transcription

1 Using Excel to Produce a Stocking Table By David R. Larsen, March 14, 2018 Objectives: In this lesson, we will build a Stock tables from two sample plots of example data. We typically start from data collected on plots of some size. For each tree we have a plot number, a tree number, a species code, a Diameter at Breast Height (DBH), a merchantable height, often a percent soundness and a mortality code. Figure 1. An example to the typical data from example plot.

2 Figure 2. We add a column for the expansion factor. In this case, we had 1/5 th acre plots.

3 Figure 3. Next, we next calculate the basal area for the tree. Figure 4. We then calculate the basal are per acre represented by this one tree.

4 Developer tab. If you do not have a developer tab as in Figure 5. Follow these steps. Go to the File tab and click Options. Figure 5. A Excel with no Developer Tab. Figure 6. The File tab.

5 Figure 7. The options tab. Figure 8. List of tab note Developer tab is not checked.

6 Check the developer tab like this. And return to the spreadsheet page. Now your menu bar will look like this. Figure 9. Main menu with Developer tab.

7 Select the developer tab and you should see a menu that looks like this. Click the insert tab. Under the insert tab, you will find a link for a module. Click of the module to create a blank new module window. Then use your web browser to this web site at (oak.snr.missorui.edu/forestry_functions/)

8 Mover to the lower part of the web page. Beer s tree volume equations link.

9 Navigate down the page to the Visual Basic Code and copy the code.

10 Then paste the code into the module window you created. It should look like this.

11 This process created a new function in you excel spreadsheet. You can use it like this to calculate the cubic volume for the log in this tree. You can calculate the board foot volume with the same function using this instruction in the next cell. We next make the number equal the volume that the tree represents per acre.

12 We now go to a new sheet and make a table that looks like this. This table has a key that is our species codes and other fields that are the reporting name, green weight and the 12% dry weight. We next add a column next to the Species column call spcode.

13 We next inter the vlookup function with the three files the first is the Species Number we want to look up. The second it the range of the table we make in the other sheet, and the column in that table we want to return. It will print the name of the specie in the spcode column. We will use the same function and table in Column P to enter the dry weight for the species. We then expand the weight to a per acre basis. Now out spreadsheet should look like this. Next, we will create a Pivot table to create a cross-tabulation for our table. Here is the pivot table tab on the insert ribbon.

14 Be sure to have you cursor somewhere within the data. You should see something like this.

15 We will make a layout like this. In addition, the table will look like this.

16 Next, we will copy the white part of the table. And paste back on a new sheet like this. These numbers are the sum of all plots so we will correct this as follows. We will make a copy of some cells such as the labels.

17 The tree are just a count of how many trees were sampled. I added a field with how many plots were sampled. Each plot once expanded is on a per acre basis so we need to average all plots together. Since the numbers in columns E through H are sums we just need to divide by number of plots as in the TPA cell. We have now continued the process and done some formatting with bold and top and bottom borders. In the next table, I adjust the number of decimals to make the number easier to read.

18 Now we can copy the table and past it into Word.