Comparing trees

 

Text Source: Focus on Newfoundland Forests, Department of Natural Resources

Trees are classified into two broad categories: coniferous (evergreen) or deciduous.

Coniferous:

1. Leaves remain on the tree for two or more seasons.

2. Seeds are contained in cones.

3. Wood is soft and resinous (softwood).

 

Deciduous:

1. Trees bear broad leaves that are shed in autumn, although not all deciduous trees have broad leaves.

2. Wood is generally harder than that of conifers (hardwood).

 

Identifying trees by leaves

 

Coniferous:

Leaves may be differentiated by shape—for example, leaves of white pine are triangular in cross-section, while fir leaves are flat.

Some needle-like leaves occur singly on the twig, while others occur in bunches. Spruce and balsam fir needles occur singly, while white pine has needles in clusters of five. Red pine have two needles per cluster.

Deciduous:

Leaf shape, leaf margin, leaf type (simple or compound) and leaf arrangement on the twig are all important to note in tree identification.

For example, poplar leaves are generally oval. Most birch leaves are triangular, and mountain white birch are heart shaped. Willow leaves are long and slender.

Leaf edges (margins) may differ - maple leaves are loped, while black ash, dogberry, and birch leaves have toothed edges.

Maple, aspen and poplar have simple, one-piece leaves, while dogberry, black ash and chestnut have compound leaves made of several leaflets.

On some trees, such as poplar and cherry, leaves are attached alternately on the twig. On others such as maple or ash, leaves are opposite each other.

Identifying Trees by Bark

 

Tree bark is differentiated by colour, texture, hardness and pattern. White birch is easily identifiable by its white, easy-to-peel bark, which peels from the tree in sheets or strips. Most tree bark changes as a tree ages. Young balsam fir have thin, smooth bark that may be grayish –green in colour.  The bark thickens and becomes a dark, grayish brown as the tree matures.

 

Identifying Deciduous Trees
by Twigs and Buds

 

Twigs and buds can be used to identify deciduous trees during the winter. Like leaves, buds are arranged on the twig in either opposite or alternate patterns. You may also note the size, colour, stickiness  and hairiness of the buds.

 

Identifying Trees by Silhouette or Shape

 

Tree species may be differentiated by general shape or outline. White pine trees usually have branches at right angles to their trunks. In sheltered areas, the overall shape is oval, but the shape may be contorted by prevailing winds, giving the tree a bent and sculpted look.

Silhouettes of deciduous trees are also distinctive in winter or summer. Weeping willow branches droop, while poplars are tall and slim. Oaks usually have short, sturdy trunks with a few large branches. Maples may have a few large branches but have larger, spreading limbs supporting wide, full crowns.