Of easy cultivation, it prefers a good moist well-drained soil but succeeds on most soils, though it is more likely to become chlorotic as a result of iron deficiency on alkaline soils. Grows well in heavy clay soils. Trees need full light and a lot of space. This species is one of the most shade tolerant of the N. American maples. It tolerates atmospheric pollution and so is often used as a street tree, though it can suffer from soil compaction and the use of salt on the roads in frosty weather. Tolerates a pH in the range 4.5 to 7.3. Hardy to about -45°c when fully dormant. A fast-growing tree for its first 40 years in the wild, this species is not a great success in Britain, though it does better than once thought. It grows well in Cornwall. In cultivation it has proved to be slow growing when young. Trees can live for 250 years in the wild. A very ornamental tree but a bad companion plant, inhibiting the growth of nearby plants. This species is commercially exploited in America for its sap. Along with its sub-species it is the major source of maple syrup. There are some named varieties. The sap can be tapped within 10 - 15 years from seed but it does not flow so well in areas with mild winters.
The sap contains quite a large proportion of sugar. This can be used as a refreshing drink, or be concentrated into a syrup by boiling off the water. The syrup is used as a sweetener on many foods. The sap can be harvested in late winter or early spring[, the flow is best on a warm sunny day after a frost. Trees on southern slopes in sandy soils give the best yields. It is best to make a hole about 7cm deep and about 1.3 metres above the ground. Yields of 40 - 100 litres per tree can be obtained. The best sap production comes from cold-winter areas with continental climates. The sap contains 2 - 6% sugar, thus about 32 litres are required to make a litre of maple syrup. Self-sown seedlings, gathered in early spring, are eaten fresh or dried for later use. Seeds - cooked. The wings are removed and the seeds boiled then eaten hot. The seed is about 6mm long and is produced in small clusters. Inner bark - cooked. It is dried, ground into a powder and then used as a thickening in soups etc or mixed with cereals when making bread.
Seed - best sown as soon as it is ripe in a cold frame, it usually germinates in the following spring. A lot of the seed is non-viable, it is best to cut a few open to see if there is an embryo. An average of 95% germination can be achieved from viable seed. Pre-soak stored seed for 24 hours and then stratify for 2 - 4 months at 1 - 8°c. It can be slow to germinate, sometimes taking two years. The seed can be harvested 'green' (when it has fully developed but before it has dried and produced any germination inhibitors) and sown immediately. It should germinate in late winter. If the seed is harvested too soon it will produce very weak plants or no plants at all. When large enough to handle, prick the seedlings out into individual pots and grow them on until they are 20cm or more tall before planting them out in their permanent positions. Layering, which takes about 12 months, is successful with most species in this genus. Cuttings of young shoots in June or July. The cuttings should have 2 - 3 pairs of leaves, plus one pair of buds at the base. Remove a very thin slice of bark at the base of the cutting, rooting is improved if a rooting hormone is used. The rooted cuttings must show new growth during the summer before being potted up otherwise they are unlikely to survive the winter.
Found in a variety of soil types, doing best in deep rich well-drained soils from sea level to 1600 metres. Rich usually hilly woods.
|
|