Rock Maple

Acer glabrum

Physical Characteristics

Acer glabrum is a deciduous Tree growing to 9 m (29ft 6in) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 5. It is in flower in April, and the seeds ripen in September. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required). and is pollinated by Insects. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Distribution

Western N. America - Alaska to California, west to New Mexico.

Habitats

Woodland Garden Secondary; Sunny Edge; Dappled Shade;

Edible Uses

Edible Parts: Inner bark Leaves Seed Shoots Edible Uses: Condiment Edible young shoots - cooked. They are used like asparagus[85]. The seedlings, gathered in early spring, are eaten fresh or can be dried for later use[213]. The dried crushed leaves have been used as a spice[257]. Seeds - cooked. The wings are removed and the seeds boiled, then eaten hot[213]. The seeds are about 6mm long[82]. Inner bark[85]. No more details are given but inner bark is often dried, ground into a powder and then used as a thickening in soups etc or mixed with cereals when making bread. An emergency food, it is usually only used when all else fails[85]. Sap: Can be tapped in late winter to produce a sweet syrup after boiling down. Raw sap is watery and lacks sweetness, but once concentrated it becomes a nourishing drink or syrup rich in minerals [2-3]. Leaves: Young leaves are edible when cooked. Raw leaves are bitter and astringent, but boiling reduces the bitterness. Rocky Mountain maple tends to have less hairy leaves than other western maples, making them more pleasant as a cooked vegetable [2-3]. Buds and Flowers: Winter buds and flowers are presumed edible, though poorly documented. Buds have a bitter, lettuce-like flavor, improved by cooking. Flowers are green, mild, and chewable, but not widely referenced as food [2-3]. Fruits (samaras): Young fruits are edible before the wings toughen. They can be eaten raw in small amounts or better cooked to reduce astringency [2-3]. Inner Bark: Technically edible when dried and ground into flour, but tough, fibrous, and nutritionally poor. Considered a survival food only [2-3].

Medicinal Uses

Antiemetic Birthing aid Cathartic Galactogogue A decoction of the wood and bark is said to cure nausea[213]. Another report says that this is specifically the nausea caused by smelling a corpse[257]. An infusion of the bark has been used as a cathartic[257]. A decoction of the branches, together with the branches of Amelanchier sp., was used to heal a woman's insides after childbirth and also to promote lactation[257].

Known Hazards

None known