Common Name: Black Maple

General Information

Acer saccharum nigrum is a deciduous tree with a wide, spreading crown at maturity; it usually grows 18 - 22 metres tall, exceptionally to 30 metres or more. The straight, cylindrical bole can be 90cm in diameter[, ].
This species is commercially exploited in America for its sap[, ]. Along with Acer saccharum and the sub-species Acer saccharum grandidentatum it is the major source of maple syrup[]. A very ornamental tree, there are some named varieties[, ]

Known Hazards

None known

Botanical References

, ,

Range

Eastern N. America - Quebec to Alabama, west to South Dakota and Arkansas

Habitat

Rich calcareous or alluvial woods[]. Found in a variety of soil types, near streams, rivers and in rich woodlands, usually below 750 metres but up to 1650 metres in the south of its range[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	20.00 m
Growth Rate	Slow
Cultivation Status	Ornamental, Wild

Cultivation Details

Acer saccharum nigrum is a very cold-hardy plant, able to tolerate temperatures down to around -35°c when dormant[]. Down to around -45°c according to another report[].
This species is not a great success in Britain[], though it does better than once thought[]. It grows well in Cornwall[].
Of easy cultivation, it prefers a good moist well-drained soil but succeeds on most soils[, ]. Chlorosis can often develop as a result of iron deficiency when the plants are grown in alkaline soils, but in general maples are not fussy as to soil pH. Grows well in heavy clay soils. Trees need full light and a lot of space[].
Slow growing when young[]. Plants produce prodigious root growth but very little top growth in their first year from seed[]. Trees grow rapidly for their first 25 years in the wild, but then slow down and only occasionally surviving for more than 200 years[].
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.
A bad companion plant, inhibiting the growth of nearby plants[, ].
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[].

Edible Uses

The sap contains reasonable quantities of sugar and can be used as a drink or concentrated into a syrup by boiling off the water[, , , , , , , ]. The syrup is used as a sweetener on many foods.

Seed - boiled then roasted[, , ]. 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[, ].

Medicinal

A decoction of the inner bark has been used in the treatment of diarrhoea[].

Other Uses

We have two reports that the leaves of maple species, when laid in layers between crops such as apples, carrots and potatoes, have a preservative effect[, ]. The reports do not name any specific species[].

Wood - close grained, tough, hard, heavy. Used for furniture, ship building, etc[, , , , ].
The wood is a good fuel[].

Propagation

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 early summer . 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.