Identifying old wood (iv): a case study on old drawers

Sometimes it is possible to narrow down a wood based on a time period. For instance if a house was built in the late 1940’s, and speculation is that the trim is chestnut, this is unlikely to be the case, as chestnut blight all but wiped out chestnut trees by the 1940s. If the house is from before 1930, this might be more plausible. In Toronto in the 1920s many of the ads for houses contained phrases like: “kitchen finished in Georgia pine”, “downstairs is trimmed in chestnut”, and “oak floors of best quality throughout”. Georgia pine is actually Longleaf pine (Pinus palustris), but I guess it sounded cooler in an advert then “longleaf”.

Is this Longleaf pine?

In our semi-detached house there was a built-in hallway closet that had three large drawers at the bottom, and a large two-door cabinet at the top. Not really practical from a storage point of view, so years ago I pulled it apart, and made it a recessed closet. I like retaining the feel of the old house, but some things need to move on. I kept the wood from the drawers, and the doors (which will be upcycled sometime in the future). The trick is identifying the wood. I would imagine as it was used for both the drawers, and the shelves inside the cabinet, that it was something like a pine, or maybe a Douglas fir? The lack of pores implies a softwood. The wood itself has fairly tight growth rings, signifying older growth lumber, with very few knots.

Might it be Georgia pine? There are numerous publications from the period, like “The Canadian Builder-Carpenter”, that discuss the use of Georgia pine for cupboards, trim, and doors. Before European settlement it dominated eastern North America, covering 360,000 km². By the early 1930’s most of the “limitless” virgin Georgia pine forests were gone. In 1928 botanist Roland Harper described the Longleaf Pine as a tree with “probably more uses than any other tree in North America if not in the whole world…”.

Identifying old wood (iii) a case study on chestnut

Pulling apart the mantle in the living room to replace it with one made of cherry, I thought, hey, why not check to see if it is chestnut. The first sign that the wood seemed different was that it felt light weight. So chestnut is most similar to oak. One of the biggest differences is weight – chestnut is about 60% the weight of white oak. So I thought I would take an initial check and calculate the weight of a piece of it. The weights were in the table I made in the previous post. By first measuring the volume, and weight of the piece of the wood: 9.9in³ and 0.1742 lbs, it is then possible to calculate the relative weight in lbs/ft³. This turned out to be 30.39 lbs/ft³, which equates well with the weight of chestnut.

 

Now to confirm this involves looking at some of the macro features of the piece of wood. The first thing to notice is that there are no visible rays, which implies that it is not of the oak family. Here’s a photo showing the growth rings in the block of wood. There is an abrupt change from earlywood to latewood, and the pores become extremely small.

A close-up view confirms the lack of rays, or rather the rays are not visible (usually one cell wide). The pores are also oval in shape, and has visible tyloses, which is consistent with what should exist in a piece of chestnut.

What to do with the chestnut once I have salvaged it? Likely I will use the wood in a small chest of some sort.

 

 

 

Identifying old wood (ii) a case study on chestnut

When we first moved into our house, it was suggested that the trim was chestnut. The American Chestnut is an incredibly versatile wood. Before the blight destroyed the majority of American Chestnut trees in the early 1900s, these trees could grow in excess of 100ft tall, with diameters of 5-7 feet. Accidentally introduced into the US in 1904 on Asiatic chestnut trees, the blight Cryphonectria parasitica ravaged the chestnut forests over the next 30 years, killing billions of trees. Before the 1940s, chestnut was widely used because it was abundant, and had good woodworking properties. In Toronto it must have been extensively used for trim purposes from 1900 to the late 1930s. My house was built in 1926, by which time this lumber had been drying for a number of years before being processed.

The problem with chestnut is that it looks quite similar to oak. So how does one tell them apart? By looking a little closer. Here is a sample of what is supposedly chestnut.

Both chestnut and oak are ring-porous – chestnut has bands of large earlywood pores (which appear more oval than round), and some tyloses (as does white oak). Chestnut can be easily distinguished from that of the oaks by looking for the rays. Rays are groups of cells that extend from the pith to the bark. All species of trees have rays but they vary in size. In chestnut, the rays are small and cannot be seen with the naked eye. In the oaks, the rays are very wide and thus are readily visible to the naked eye.

The presence of the rays, says the piece of wood is not chestnut, and the existence of the tyloses, implies that the wood is most likely white oak. Below is a table of common differences between wood characteristics of white oak, red oak, and chestnut.

The basics of identifying wood (ii): rings and pores

As mentioned in a  previous post, the rings form the most visible structure in a transverse surface, or cross-section through a tree, or branch. Can it be used to identify a piece of wood? Only vaguely in so much as some trees have very distinct rings, for example oak, ash, douglas fir, maple. Others have more obscure rings, e.g. birch, beech, ebony, purpleheart, poplar. This is very evident in tropical hardwoods where growth can occur all year round.

More important are pores.  Pores, or vessels, are the small circular holes visible on a cross-section of wood, and do not appear in softwoods. These vessels serve as the tree’s plumbing, transporting sap throughout the tree. The size and distribution of these pores helps determine the type of wood. So ask the question – does a cross-section of the wood show pores? YES – then it’s a hardwood, NO, then its a softwood. Some pores have contents, sometimes a result of transforming from sapwood to heartwood. One of these fillers are tyloses- which grow in open pores and can completely fill them. A good example is the difference between red and white oak. White oak contains tyloses, and does not absorb water the way red oak does, making it better for shipbuilding (check out this video to see why).

Hardwoods have three different types of pore arrangement:

• ring-porous: pores occur mainly in the earlywood, causing an abrupt transition to latewood which is very distinct. Latewood pores are more difficult to see. (oak, ash)
• semi-ring-porous: The pore transition from large to small diameter within a growth ring is gradual. (black walnut, hickory)
• diffuse-porous: The pores are uniform in size across the entire growth ring. (poplar, maple), often with no clear earlywood/latewood pore arrangement.

Here are some examples:

Three types of pore: ring-porous (oak), semi-ring porous (walnut), and diffuse-porous (hard maple)

And a close-up of what the pores would look like:

 

 

The basics of identifying wood (i)

The next few posts are just a basic overview of trying to identify wood, looking at some of the more common characteristics. So if we have an old piece of wood, how do we identify what it is?

The easiest way is to look for distinguishing characteristics, some of which will separate hardwoods from softwoods. These can include rings, pores, grain (long surface), rays, hardness, weight, smell, and colour. First some basics. All wood is designed to carry sap, and it starts life as sapwood. As a tree ages, the inner core of the tree requires more for structural support, and hence the sapwood is modified to become heartwood. An example of a cross-section from an elm tree is shown below. Notice the distinct difference between sapwood and heartwood (this isn’t always the case).

The photograph also shows the grow rings. Both softwood and hardwood have rings, although certain types of trees (e.g. tropical near the equator) lack apparent rings, because the growth cycle is all-year around. In temperate regions, wood is formed only during spring and summer, and the wood formed in the summer differs from that formed in the spring.

Springwood (or earlywood) is usually light in colour, light in weight, and contains numerous tubes to transport sap (i.e pores), and is only moderately strong. When summer takes over from spring, the tree changes the character of the wood it produces. Nutrients can now travel upwards through the springwood, but the tree needs more structural support. Summerwood (or latewood), is usually fibrous, with thick, strong walls, and small cavities – it is often darker in colour. The width of annular growth rings varies depending on water availability, sunshine etc. Fast growing trees may have thick rings, whilst slower growing trees have narrow rings. The other structure most apparent are rays – radial structures which occur perpendicular to the growth rings, used for the radial transport of sap.

The first thing to determine is of course is the wood a hardwood or softwood? A softwood is a coniferous or needle-leaved trees. It is called softwood because it is generally soft and easy to work, and it has a simple structure. A hardwood (deciduous) is a tree that has broad leaves, and is sometimes physically harder than softwoods and also denser. A notable exception is poplar. Here are some basic differences:

• Softwoods have rays that are very narrow, and barely visible.
• Softwoods contain resin (often giving them a characteristic turpentine smell).
• Hardwoods have visible pores.
• Hardwoods often develop large and characteristic rays.

 

Identifying old wood (i)

Old houses are full of good quality, old-growth wood. Wood like chestnut which has long since disappeared from the lumber mills. It is often reclaimed in the form of beams when large old buildings are deconstructed, but this is not always the case with houses. (For anyone interested, Baltimore Brick By Brick is an excellent blog on unbuilding). One of the challenges of reclaiming old wood is being able to  identify it. How does one go about this?

There are many characteristics, including both macroscopic (visible to the naked eye) and microscopic features. Here are some macroscopic characteristics to consider: rings, pores, grain (long surface), rays, hardness, weight, smell, colour. I am going to write a few posts on the basic steps of wood identification. For identifying vintage wood, I strongly suggest getting a copy of  R. Bruce Hoadley’s book – “A Field Guide to Identifying Woods in American Antiques & Collectibles“. It’s packed with features of wood, tools and techniques, and a compendium of commonly used furniture and antique woods showing identification criteria and sample artifacts.

Here are some additional resources for anyone looking to identify the wood used in a piece of furniture.

Resources:

So there are a number of resources out there to help identifying old wood. Mostly this is a visual process, and only becomes difficult if you are required to go to the micro level of investigation. Some of these books are somewhat older, but they are well written.

The Wood Database is an exceptional online database of wood species. Here’s a great article on softwood anatomy on The Wood Database.

Edlin, H.E., “WHAT WOOD IS THAT?“, Thames and Hudson, London, 1969.
– This is an excellent book which has gone through a number of printings. The book has three parts. Part I deals with a brief introduction to the history of lumber. Part II explores wood identification, using 14 keys. Lastly, Part III describes forty common trees and the wood derived from them.

Core, H.A., Côte, W.A., Day, A.C., “Wood Structure and Identification“, (2nd ed.), Syracuse University Press, 1979.
– This book examines the wood structure, at the “gross, microscopic, and ultrastructural levels”. The book provides an excellent key to differentiating hardwoods, and softwoods based on There is an indexed glossary of 75 wood species, with associated low-power photomacrographs.

Hough, R.B., “The Woodbook: The Complete Plates“, Taschen, 2013.
– This book has a nice set of photographs of each wood showing tangential, radial and cross-sections in colour.