What is on Your Woodlot
Chapter 5 - What is on your Woodlot?
by Michael Rochester
If you own a woodlot, or want to buy one, you may want to know what is on it. Many people can't tell the trees from the forest. There is a science dedicated to this subject and it is called "forestry". Forestry is the science of planting and taking care of trees and the forest. It originated from the privilege of managing the "royal forest" in 1859. The French word "foresterie" originated in the 1690's and the French use the word "forestier" when referring to foresters today. Enough history for now, let's talk about the different trees you may find on your woodlot. The species composition may change from one area to another due to climatic influences, terrain, and soils.
One way to find out what is on your woodlot is to hire a forester to do a timber inventory or write a forest management plan. The forester will inventory the forest, make a type map, and recommend what you should do based on your objectives. With this information, you could then investigate the characteristics, uses, and value of your trees further. Your values may be different than just the monetary value. If you want to manage your woodlot for the benefit of wildlife or recreation, then the trees will have a different meaning for you. If you are interested in the monetary value of your woodlot, then your management goals will be to maximize your investment. Either way, this chapter assumes that your knowledge is limited about the forest and I will cover the basics.
Your woodlot may have similar trees growing together in groups. Foresters refer to these groups as "forest stands". The forest stands may have trees with leaves or they may have trees with needles. Many forest stands have trees with both types of these trees. One type of tree will often be more dominant than the other. We identify trees by their form, leaves, seeds, cones, bark, and twig characteristics. Trees that have leaves, and then lose their leaves in the winter, are called "deciduous trees". Trees with needles are called evergreens, softwoods, or conifers. These trees are cone-bearing trees. They retain their needles in the winter. There are a few exceptions. Larch is an evergreen in Maine and it's needles turn yellow in the late autumn and drop off. Tamarack, also called "mackmatack" and "American larch", is not an evergreen but it's needle-like leaves turn yellow in the autumn and drop off.
When foresters and people associated with the woods industry talk about trees, they usually refer to them as softwoods and hardwoods. In Maine, the most common softwood used for timber are balsam fir, spruce (white, red, black), white pine, cedar, and larch. The hardwood trees include the maples, birches (white and yellow), oak, beech, ash, and others. We also have aspen and balsam poplar but these hardwood trees are used mainly for chips because their fiber is softer. The Maine Forest Service's Bulletin # 24, "Forest Trees of Maine", list 14 native conifers, 57 native hardwood trees, and 29 exotic species that were introduced here. The "Forest Trees of Maine" booklet would be an excellent resource tool for any woodlot owner. There is a $15 fee for the booklet. Follow this link to get yours:
Mapping Your Woodlot
If you would like to try mapping your woodlot, the first thing to do is identify the forest stands. Your choices will be softwood stands (75% or more softwood), hardwood stands (75% or more hardwood), or mixed wood stands (something in between). In this classification system, you use the dominant trees in the canopy for the classification. To make this task easier, you should get an aerial photo of your woodlot. An aerial photo can help spot the differences in the stands as you try to identify them. You can draw a line around the different stands and make some notes. On an aerial photo, softwood stands usually look darker than hardwood stands and mixed wood stands are somewhat in-between. You will still have to go into the woods and verify your findings. The aerial photo can also help you identify where you are. Use landmarks like roads or other features that you can identify on your photo. I never visit a woodlot without an aerial photo, compass, and a GPS. The GPS can be used to mark corners, points of interest, or starting points for navigation. I will discuss the GPS in a later chapter and how you can use one. After you know the area each stand encompasses, you then need to try and describe what each stand is composed of. Use a field notebook or the back of your aerial photo. Assign each distinct area with a number like A-1 (Area 1). You can use codes to help you describe each stand. Here are a list of codes.
Typical codes and their definitions:
A-1: Area 1, A-2: Area 2, etc.
H: 75% or more hardwood
S: 75% or more softwood
M: In between hardwood and softwood definition, (i.e.: hardwood - 60%, softwood - 40%)
1 – 0’ to 30’ (stand height)
2 – 30’ to 50’ (stand height)
3 - > 50’ (stand height)
A – 100% crown closure
B – 70 to 100% closure
C – 30 to 70% closure
D – 0 to 30% closure
Crown closure is defined as the percent of canopy overlaying the forest floor or how much of a stand of trees is covered by the crowns of live trees. You make this estimation by looking up at the crowns and trying to determine how much space is covered by crowns and how much space is open to the sun or light.
Use the codes above to label your stands. A distinct stand may have a code similar to this: A-1/M2B. Area 1 has mixed wood, 30 to 60 feet tall, with a high but not full crown closure.
1. The kinds of trees present (softwood, hardwood, or mixed wood).
2. The size of the trees (height and size of the trees - seedlings, small, medium, or large).
· Seedlings and very small trees less than 1 inches in diameter (usually less than 15 feet tall).
· Small trees are usually 1 to 4 inches in diameter (diameter at breast height - dbh) (usually 15 to 40 feet tall).
· Medium trees are 4 - 8 inches, dbh (40 to 50 feet tall).
· Large trees are over 8 inches, dbh (50+ feet tall).
3. The tree spacing (thick, thin, intermediate) helps determine the crown closure (how much light can reach the forest floor.
· Thick spacing is when the branches are touching or it is hard to walk between the trees.
· Thin spacing is when there is large spaces between trees.
· Intermediate spacing is a combination of the two.
A distinct stand may have a code similar to this: A-1/M3B. Area 1 has mixed wood, 45 to 60 feet tall, with a high but not full crown closure.
4. Other features to note for each area (regeneration, shrubs, wildflowers, brooks, wildlife, etc.)
Maps are a very important tool in understanding your woodlot. There are different types of maps and each one will give you a new perspective of your woodlot. Let's examine 4 of them and where you can find them.
Aerial photo: As described earlier, aerial photos are essential for you to get an overview of your woodlot. They can show the forest types, boundary lines, streams, roads, openings or fields, etc. You can use them to help map out your woodlot and make future plans. There are numerous sources to get aerial photos.
· Farm Service Agency (FSA): They may also have your woodlot mapped out or help you do it.
· Natural Resource Conservation Service (NRCS): Same services as FSA.
· Consulting foresters: They usually have their own mapping software and can help GPS your boundaries and other features.
· Maine Forest Service: The field foresters have access to aerial photos and will help you.
· Google Maps: They have high resolution photos you can print.
· Bing Maps: They have services similar to Google.
Topography maps: These maps are very useful to help interpret the terrain and can be used in conjunction with aerial photos, especially if they are same scale. Topo maps show the elevations, steepness of slopes, important features, brooks, and more. I have included 2 sources where you can find them. Search the web for topo maps and there many more sites available.
· USGS Topographic Maps (USGS): Download and print topo maps and aerial photos on the same site. Fairly easy to navigate. Web address: http://topomaps.usgs.gov/
· The Maine Map Gazetteer: This book covers statewide mapping. Not as detailed as USGS but it is still a very good map source with many details. This book is available for purchase everywhere.
Soils maps: As described in an earlier section, these maps are invaluable in planning your future woodlot, plantings, harvesting, road building, etc. Refer to the Soils chapter for more information on accessing these maps. The soils maps I use now incorporate an aerial photo overview and that makes pinpointing soil locations much easier.
Type map: The type map is your own personal map of your woodlot. It can also be your working copy of your woodlot. It is usually drawn to scale and delineates the timber types, forest stands, streams, roads, fields, and any other features on your woodlot. If you have an aerial photo with your lines indicated, you can put a blank piece of paper over it, and trace the outline on a window using the light shining through. Also mark out roads, streams, fields, etc. The type map should be the same scale as your aerial photo. After you have all of the information on it, make a few copies for future use. You can then update the map as you conduct activities on your woodlot. You can also use your type map to indicate the activities you have planned.
There are codes on the type map and they are used to describe each forest stand and referenced areas. There is a scale to reference the distances and a legend is included for other symbols.
The trees on your woodlot will be either softwood, hardwood, or mixed growth trees and grow in various stands. There are different species and the sizes and heights will vary. Maps are a great tool and you should acquire some of the maps I have talked about to help you better understand your woodlot. There are many books that can help you identify the trees, shrubs, wildflowers, animals, and everything else on your woodlot. You could go on field trips with knowledgeable people to help you understand more about your woodlot. There are a lot resources out there to help you and I have mentioned many in earlier sections. An excellent organization to join is the Small Woodland Owners Association of Maine (SWOAM). They can offer you assistance through articles on their website and events they hold periodically (http://www.swoam.org/Home.aspx). Consulting foresters are very knowledgeable about woodlots and their services can help you get off to a good start.