It takes knowledge and experience to identify the different wood species used for tools. There are several good books on the subject and you can also get wood sample kits from wood supply companies to help with identification. Perhaps the best way to go about the identification of wood is to have an experienced person label examples for you, maybe even using some of the tools you've already collected, pointing out the distinguishing features of each species.
Wood identification is much easier in the classroom with a fresh clean sample. The two items that make up grain, as seen by the naked eye, are the longitudinal pores, which form the annual rings, and the rays.
Pores are the openings in the tiny tubes running up the tree, that show up as holes when the tree is sawn across the trunk. The tree's annual rings result from having the more, or larger, pores at the start of the growing season. If the pores are visible with the naked eye, the wood is termed open grain. If 5X magnification is needed, the wood is called tight or close grain.
The pores appear differently when the log is sawn lengthwise. They now appear as tiny groves, such as you would get by cutting a bunch of straws lengthwise. In antique tools these may be filled with grime, making them appear to be darker. If the cut is through the center of the tree, the annual rings appear as parallel lines. If the cut is at right angles to the radial section, the rings "wander."
The rays appear solid and flattened and run outward from the center of the tree. In the cross section, they are seen as thin lines running from the core to the bark. In the radial section, they become irregular flecks; in the flat section they are tiny straight lines. The rays are an important identification and usually need 5X magnification.
Two other definitions: the sapwood is a donut section of wood next to the bark; it is usually much lighter in color than the remaining heartwood. With just this information you can identify the 20 or so common tool woods. The clearest view of the pores and rays requires slicing the wood with a sharp razor, something that most collectors would never think about doing, except it could have been done on a hidden part. Cleaning the surface with # 0000 steel wool will do just as well. This will also help in determining the true color, as most tools have an aged surface, (patina) that deepens their natural color.
The wood most commonly used for tools is beech, particularly in planes. Although it is a distant cousin to birch and maple, the three are not easy to tell apart. They are light colored woods, but can patina to almost a walnut color. Maple, used occasionally for handles and braces, is rarely used for planes, so the choice for molding planes is almost always birch or beech. Early American plane-makers, particularly those in 18th century New England used a lot of birch, but wooden planes made after 1800 were most often beech.
Boxwood is used in molding plane wear strips, plow planes and miniatures. When this light yellow to buff wood paginates and darkens, it might be mistaken for maple. Maple's end grain under 5X has a variety distinct ray lines, while boxwood's rays are so thin and close together that they could have missed even under magnification. Apple, particularly its sapwood, is often taken for boxwood, but it is much grainer and has a pinkish-brown color. Cherry and apple were the fruitwoods most often used. Cherry has a reddish hue to its brown color, and although it looks very much like apple, it is grainier. Another characteristic of cherry, often used for decorative effect, is the contrast in color between the sapwood and the heartwood. The sapwood is almost white. Many woodworkers used the sapwood and the heartwood in the same piece for effect.
The woods in the next group are not botanical "cousins," but all are dark in color. Ebony can be either jet black, or have dark brownish streaks or hues. You'll know it's ebony because of its extremely smooth surface. Ebony is also very heavy and it sinks in water. Rosewood shows color strikes that range from reddish brown to almost black. There are many species of rosewood, the most common used in tools being East India rosewood, which is darker and more solid in color. Another species, Brazilian rosewood, was used starting in the late 19th century. It is more orangey in hue and dramatic in grain figuring. Lignum vitae, another wood that sinks, also has strikes resembling rosewood but varies (in the same piece of wood) between brown and yellow and, unlike rosewood, is very tight-grained.
Last in this category are the mahogany's, generally moderately dark brown, with occasional reddish hues, often highly figured and moderately open-grained. They range from moderately heavy to very heavy in weight. There are so many species of mahogany, which grow in South and Central America and Africa that only an expert can tell them apart. Mahogany was most commonly used for levels, for infill in English planes, and for measuring instruments. Although you may find some color strikes in the grain, it will not be as valuable as the rosewoods and that's one of the best ways to tell them apart.
Handles that need to absorb shock such as axes and adzes; are generally made of hickory, a though, twisty, open-grained medium brown wood. You will be able to see long grain lines in hickory. Oak, rarely used for tools is an extremely open-grained wood with heavy ray flecks.
Hornbeam is a European wood used by German and Austrian toolmakers. It is a light colored, heavily flecked wood. French Cormier is a softer wood similar to our apple. Both are common in planes and braces that originate in those countries.
I hope this information helps you to identify the woods in your antique tool collection.