B. Sugar Maple

The Sugar Maple (figure 3.2) is a deciduous tree with a round crown. It is a prominent tree in the hardwood forests of eastern North America. Also Sugar Maple is grown in parks and gardens in Europe. It reaches heights of 15 metres (50 ft) to 24 metres (80ft) tall. Sugar Maple are distinguished by opposite leaf arrangement. Theleaves are deciduous, 8-15 cm long and equally wide with five palmate lobes. The basal lobes are relatively small, while the upper lobes are larger and deeply notched.

In contrast with the angular notching of the Silver Maple, however, the notches tend to be rounded at their interior. The fall color is often spectacular, ranging from bright yellow through orange to fluorescent red-orange. The leaf buds are pointy and brown colored. The recent years growth twigs are green, and turn dark brown.

The flowers are yellow-green. The fruit is a double samara or “maple keys” with two winged seeds. These seeds occur in distinctive pairs each c

Figure 3.2 Sugar Maple

ontaining one seed enclosed in a “nutlet’ attached to a flattened wing of fibrous, papery tissue. They are shaped to spin as they fall and to carry the seeds a considerable distance on the wind. Seed maturation is usually in a few weeks to six months of flowering, with seed dispersal shortly after maturity. Maples are important as source of syrup and wood. In North America the sap of this species is used to make Maple Syrup (figure 3.3). Some of the larger maple species have valuable timber, particularly Sugar Maple in North America. Sugar Maple wood is one of the hardest of the maples, and is prized for furniture and flooring. Bowling alleys and bowling pins are both commonly manufactured from sugar maple. Trees with wavy wood grain, called “birdseye maple”, are especially valued. Maple is also the wood used for basketball courts including the floors used by the NBA, and it is a popular wood for baseball bats, along with white ash. The Sugar maple is a favourite street and garden tree, because it is easy to propagete and transport, is fairly fast-growing, and has beautiful fall color; however, its intolerance of pollution and compacted soils common to inner city conditions make it a frequent victim of maple decline.

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Figure 3.3 Sugar Maple Syrup

lso, the increased use of salt over the last several decades on streets and roads has decimated the sugar maple’s role as a “street-front” tree. It also has some of the most dense shade to be found in shade trees. The shade and the shallow, fibrous roots may interfere with grass growing under the trees. Deep well-drained loam is the best rooting medium, although Sugar Maple can grow well on sandy soil which does not become excessively dry. Poorly drained areas are unsuitable and the species is especially short-lived on flood-prone clay flats. Its salt tolerance is low and it is very sensitive to boron.

C. Silver Fir

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Figure 3.4 Silver Fir

ilver Fir or European Silver Fir (figure 3.4) is a fir native to the mointains of Europe, from the Pyreness north to Normandy, east to the Alps and the Carpathians, and south to southern Italy and northern Serbia, where it intergrades with the closely related Bulgarian Fir. It is a large evergreeen coniferous tree growing to 40-50 m (exceptionally 60 m) tall and with a straight trunk diameter of up to 1.5 m. It has a smooth bark of a greyish-brown colour, which in aged specimens becomes rugged and fissured longitudinally, and of a silvery-grey colour.

The leaves are needle-like. They are dark, rich green above, about an inch long, and on the flattened underside there is a bluish – whitestripe on each side of the midrib, which gives a silvery appearance to the foliage when upturned, as is usual on the fertile branches. The tip of the leaf is usually slightly notched at the tip. The cones are cylindrical, 9-17 cm long and 3-4 cm broad, with about 150-200 scales, each scale with an exserted bract and two winged seeds; they disintegrate when mature to release the seeds.

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Figure 3.6 An old Oak in England

ilver Fir is the species first used as a Cristmass tree, but has been largely replaced by Nordmann Fir (which has denser, more attractive foliage), Norway Spruce (which is much cheaper to grow), and other species. The wood is moderately soft and is used for general construction, interior work and paper manufacture.