Tree Spotlight – No. 2 : The Oregon Maple

Acer_macrophyllum

  • Acer Macrophyllum, the big leaf maple or Oregon Maple is a large deciduous tree in the genus Acer.
  • It can grow up to 48.89 meters (160ft 5in) tall, but more commonly reaches 15-2- meters (50-60 ft) tall. It is native to western North America, mostly near the Pacific coast, from southernmost Alaska to southern California.
  • It has the largest leaves of any maple,

  • It has the largest leaves of any maple, typically 15–30 cm (5.9–11.8 in) across, with five deeply incised palmate lobes, with the largest running to 61 centimeters (24 in). In the fall, the leaves turn to gold and yellow, often to spectacular effect against the backdrop of evergreen conifers.

  • The flowers are produced in spring in pendulous racemes 10–15 cm (4–6 in) long, greenish-yellow with inconspicuous petals. The fruit is a paired winged samara, each seed 1–1.5 centimeters (3⁄8–5⁄8 in) in diameter with a 4–5-centimeter (1 5⁄8–2-inch) wing.

  • Color/Appearance: Unlike most other hardwoods, the sapwood of maple lumber is most commonly used rather than its heartwood. Sapwood color ranges from almost white, to a light golden or reddish brown, while the heartwood is a darker reddish brown. Silver Maple can also be seen with curly or quilted grain patterns.

  • Grain/Texture: Grain is generally straight, but may be wavy. Has a fine, even texture. The growth rings tend to be lighter and less distinct in Soft Maples than in Hard Maple.

  • Rot Resistance: Rated as non-durable to perishable in regard to decay resistance.

  • Workability: Fairly easy to work with both hand and machine tools, though maple has a tendency to burn when being machined with high-speed cutters such as in a router. Turns, glues, and finishes well, though blotches can occur when staining, and a pre-conditioner, gel stain, or toner may be necessary to get an even color.

  • Odor: No characteristic odor.

  • Allergies/Toxicity: Bigleaf Maple, along with other maples in the Acer genus have been reported to cause skin irritation, runny nose, and asthma-like respiratory effects. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.

  • Pricing/Availability: Should be very moderately priced, though figured pieces such as curly or quilted grain patterns are likely to be much more expensive.

  • Sustainability: This wood species is not listed in the CITES Appendices or on the IUCN Red List of Threatened Species.

  • Common Uses: Veneer, paper (pulpwood), boxes, crates/pallets, musical instruments, turned objects, and other small specialty wood items.

  • Comments: Big leaf Maple is appropriately named, as its leaves (shown below) are the largest of any maple, commonly reaching an overall width of 6 to 12 inches (15-30 cm) across. Big leaf Maple is a commercially important hardwood timber for the United States’ west coast, where it is virtually the only commercial maple species in the region.

Science Notes: Cherry Blossom Buds

SCIENCE NOTES: Autumn Cherry Blossom Bud

How much of a tree is alive, do you think? Actually only about 1%, though all of it was alive at some time or other. Wood is made up of cells, and like all living things cells will grow and multiply, and they will die. All the wood in the middle of a tree is dead. There are only two places on a tree where you find living wood. One is a thin layer just underneath the bark, and the other place is the buds. I’m talking here not about the flower buds, but the buds which are forming the new twigs and leaves. Here’s one from the autumn-flowering Cherry Blossom, seen through Clodagh’s electron microscope.

Autumn Cherry Bud fig1

In this relatively low mag picture you can appreciate the shape of the whole bud. If we zoom in a little you notice that some parts of the delicate outer leaf structures have broken, revealing several layers of living cells.

Autumn Cherry Bud fig2

The cells in a tree multiply by dividing (which sounds like a mathematical contradiction!). A tree has different types of cells to do different jobs, such as bark, roots, leaves etc. All cells start off the same, and like the stem cells in your body they differentiate into specialist types. The cells in this picture are doing the job of protecting the growing bud: quite quickly they will break up and be replaced, in fact the strange wiggly things in the picture are the remnants of earlier protective layers.

Tree Spotlight – No.1: Cherry Blossom

rows of cherry blossom trees

  • Common Name: Sweet Cherry, Wild Cherry, European Cherry
  • Scientific Name: Prunus avium
  • Distiribution: Europe and Asia
  • Tree Size: 32-65 ft (10-20 m) tall, 1-2 ft (.3-.6 m) trunk diameter

    Colour/ Appearance: Heartwood is a light pinkish brown when freshly cut, darkening to a deeper golden brown with time and upon exposure to light. Sapwood is a pale yellowish color, typically 1-2″ wide.

    Grain/ Texture: Has a fine to medium texture with close grain. The grain is usually straight or slightly wavy.

    Endgrain: Semi-ring-porous; small pores in no specific arrangement; solitary and radial multiples of 2-3; gum/deposits occasionally present; growth rings distinct due to a concentration of earlywood pores; rays visible without lens; parenchyma absent.

    Rot resistance: Heartwood is rated as being moderately durable to non-durable regarding decay resistance. Sweet Cherry is also susceptible to insect attack.

    Workability: Sweet Cherry is easy to work with both machine and hand tools. The only difficulties typically arise if the wood is being stained, as it can sometimes give blotchy results due to its fine, close grain. A sanding sealer or gel stain is recommended. Glues, turns, and finishes well.

    Odour: No characteristic odor.

    Allergies/ Toxicity: Although there have been no adverse health effects reported for Sweet Cherry, the closely related Black Cherry Black has been reported to cause respiratory effects.

    Pricing/ availability: Typically only available in Europe (or from orchards), Sweet Cherry is usually only sold in smaller sizes or as veneer. Prices should be moderate within the tree’s natural distribution.

    Sustinability: This wood species is not listed in the CITES Appendices or on the IUCN Red List of Threatened Species.

    Common Uses: Veneer, furniture, cabinetry, turned objects, musical instruments, and carvings.

    Comments: Sweet Cherry is the Old World counterpart to Black Cherry found in North America. Sweet Cherry is said to exhibit a bit more of a color contrast than Black Cherry, and it also tends to be slightly denser and stronger. However, the tree itself tends to be smaller than Prunus serotina, and does not yield the larger sizes of lumber that are available for the American species.