Writing a Forest Management Plan: Mapping Stands

By Norma Kline, Extension Forester for Coos and Curry Counties

In the first article of the Writing a Forest Management Plan series (see link to article below), we discussed how to get started on your management plan. An easy way to gain momentum on a big project is to break it into segments. Fortunately, Oregon’s Forest Management Planning Template is organized into sections that facilitate this approach. The first section, Woodland Discovery, can be quickly addressed by using the online Landmapper tool to generate the basic property information and maps required for that section of the plan. In this article, we will discuss approaches for the next management plan section, Current Stand & Forest Health Conditions. This section will require decisions on how to delineate (map) the various vegetation types or stands on your property. How a woodland owner designates stands on their property is up to them. Woodland owners with small properties might decide to map the forest cover as one stand. Other properties might have a diverse array of age classes and species. Mapping out forest cover based on stand age and species will help landowners efficiently monitor their woodlands and plan for future needed actions. For example, we recommend monitoring recently reforested areas to help catch seedling survival problems early. Young stands should be assessed for pre-commercial thinning needs and older stands will be monitored for forest health concerns.

Some landowners might assess the forest cover across their property and see that it is fairly uniform in terms of age and species. In these instances, where there are no clear differences in forest types, consider if differences in topography and road access will require unique management approaches. For example, gently sloped areas can typically be logged with ground-based machinery while steep slopes would likely require a cable logging system. Other areas may have limited road access that constrains management. Topographic features can be identified using various online mapping platforms such as Google Earth and CalTopo or with paper USGS topographic maps.

Figure 1. Differences in forest cover.

Several approaches can be used to assess the forest cover on your property. The first step is to examine the available aerial imagery for your property. Figure 1 shows aerial imagery for a small woodland parcel near the coast. Let’s examine the imagery and determine if there are any obvious differences in forest cover. The first arrow points to a light green area of forest cover. This is a hardwood species, in this case red alder. The second and third arrows point to darker green areas of forest cover; these are conifer species. If you look closely at the differences between the conifer forest types in the second and third areas you may see that they have different textures. The second area has more shadows than the third area. In this case these shadows suggest a difference in tree sizes; the trees in area 2 have larger crowns than area 3. Using aerial imagery to assess forest types takes practice. The best approach is to take a map with imagery for your area out in the field and compare it to what you see on the ground. You can print out a map in color or use imagery available on a mapping app, such as the map program that comes with your phone or a mapping app such as Avenza that allows the user to view downloaded maps without cell service. 

Figure 2. One approach to delineating stands.

Once you get a sense of how to interpret the different textures and colors on the aerial imagery you can practice delineating stands. Figure 2 is an example of one approach to drawing stands. In this example the landowner has decided to classify their stands based on the average size and dominant species of trees in the stand. Here, the tree size is coded as S, M, L (S- seedlings to small trees up to 11” diameter, M- trees 12-29” diameter, L –  trees 30” diameter and greater). Dominate species or species mixture are coded as: Douglas-fir (DF), mixed conifer (MC), red alder (RA), mixed hardwood (MH), and mixed conifer/ hardwood (MCH). This is just an example of an approach used by this landowner. You might want to classify your stands using more growth stages such as seedling, sapling, small tree, large trees.

Once the stands are mapped out, assign stand numbers or names to each stand. Whichever way you proceed, it’s a good idea to develop a table with an associated map to help you keep track of your stands.

Stand NumberStand Description Code: tree size ( S,M, L), species
1S – RA
2S – DF
3M – MCH
4M – DF
5M – RA
6M – MCH
Table of Numbered Stands

Don’t be nervous about starting to draw your stands on a map. You can draw as many different scenarios as you want on paper printed maps or online. If you have access to a laminator, you can laminate a paper map and use dry erase pens to test out different scenarios. Google Earth Pro and Caltopo are free online mapping tools that can be used to draw and save stand polygons. There are several advantages of working digitally including the ease of editing polygons and the ability to download them to apps like Avenza for field verification. Another free mapping tool is Forest Planner; an easy-to-use drawing tool that allows users to quickly draw stand polygons that snap neatly to property boundaries and adjoining stands (Figure 3). One advantage of using Forest Planner is that the stand data is generated for each stand that you draw, including acres, aspect slope and elevation. This information can then be used to fill in the Current Stand & Forest Health Conditions form. A current disadvantage of Forest Planner is the inability to download the stand polygons to other programs.

Figure 3. Delineating stands and generating stand details with Forest Planner.

You will notice that the Current Stand & Forest Health Conditions section has a table to fill in stand information including age, diameter class, height, spacing, and tree species. This can be a general estimation for each stand. The forest management planning process does not require landowners to include a forest inventory or timber cruise for their property. Although these might be desirable to obtain for other reasons based on your management objectives. Some landowners might decide to hire a forestry consultant to conduct a basic forest inventory. But if you are able and interested in getting out on your property and learning a few basic measurement approaches, this is something you and your family can consider doing on your own with relatively inexpensive forestry tools. By collecting your own information, you will become more familiar with your woodland. You may also observe forest health issues, old roads, other interesting features of your woodland. The next article in this series will discuss taking some simple plot measurements to estimate stand diameter, height and trees per acre.

References

Writing a Forest Management Plan: Start with the Easy Sections. https://blogs.oregonstate.edu/southcoastfieldforest/2024/02/15/writing-a-forest-management-plan-start-with-the-easy-sections/

Oregon Forest Management Plan Template and Guidance. https://blogs.oregonstate.edu/forestplanning/templates/

Land Mapper. Automated and easy, produces many of the plan maps. https://landmapper.ecotrust.org/

Forest Planner. http://forestplanner.ecotrust.org/

Google Earth Pro. https://www.google.com/earth/about/versions/

Avenza. https://store.avenza.com/

CalTopo. https://caltopo.com

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