American hazel

Synonyms: American nut, Corylus americana Walter (1788), Corylus americana Marsh., Corylus calyculata Dippel, Corylus serotina Dippel, Corylus virginiana Dippel, Corylus humilis Willd., American hazel

Corylus americana – a species of deciduous shrubs of the genus Corylus (Corylus) of the birch family (Betulaceae). The range extends from the eastern part of North America (Maine, Ontario, Saskatchewan) to the southern part (Florida, Kansas), where it forms thickets in valleys, riverbanks and on slopes. Microtherm, mesophyte. In cultivation in Europe since 1798. Lifespan 150-160 years.

It is a deciduous shrub or small tree 1-3 m high. The plant is fast-growing. Vegetation occurs from late April - early May until the end of September. Young shoots with glandular bristles, pubescent; one-year-old shoots are reddish-brown, annual shoots are fissured, reddish-brown, with transverse light lenticels. Buds many-scaled, small, reddish-brown.

Leaves oblong or broadly ovate, oval to elliptical, 7-10 cm long, 5-8 cm wide, slightly cordate or rounded at the base, acute at the apex, doubly or irregularly toothed, sparsely pubescent or glabrous, light green above, bluish beneath. Petioles glandular-bristly or pubescent, 5-15 mm long.

Female catkins solitary, 7-10 cm long, 0.5 cm in diameter. Flowers in March-April.

Fruits grouped 4-6 together. The involucre is two to three times longer than the nut, reaching up to 3.5 cm in length, consisting of two almost completely separate bracts that enclose the nut and are closely folded over it as a fairly wide rim, scallop-lobed at the edge, with unevenly toothed lobes.

The nut is grooved, light brown, broadly ovoid, slightly compressed laterally, 1-1.5 cm long, edible.

Fruits ripen in August (September, October). Begins fruiting at 5-7 (9) years and produces well until 30-40 years.

Britton, N.L., and A. Brown. 1913. Illustrated flora of the northern states and Canada.

Forms: Corylus americana 'Variegata'.

Hardiness zone: 4-8 (-30°C).

Location: Undemanding to soil type and its moisture content, but grows well on humus-rich soil. Does not tolerate salinity and waterlogging. Shade-tolerant, but fruits poorly in deep shade. Tolerates urban conditions well.

Planting: Optimal seedling age is 2 years. Planting is preferable in autumn. Planting hole size 50x60 cm. Add 10-15 kg of humus, 200 g superphosphate, 50 g potassium salt and mix with the top layer of fertile soil. Before planting, seedlings should be pruned to 20-25 cm, and the roots dipped in a slurry of clay and manure. Distance between plants 4-5 m from each other, slightly denser in hedges. For good pollination, several pollinating cultivars are needed.

Care: Care consists of shallow loosening of the root circles and mulching (for example, with mown grass). Watering is recommended during dry periods.

Pruning: Should be carried out in early spring before the start of sap flow. Only sanitary pruning is required.

Propagation: Cuttings root poorly. Seed germination about 50%. For sowing, nuts dried to air-dry condition are stored in boxes layered with sand, peat or sawdust, in a dry room and in tightly closed containers, paper or cellophane bags in the refrigerator. With such storage, seed viability is retained for up to 2 years. Sowing is recommended in autumn. Seeds before sowing require stratification at 1-5°C for 3-6 months. Sowing depth 4-6 cm. Seeding rate is 50-70 g per 1 linear meter.

Pests: hazelnut leaf beetle, nut weevil, hazel tortrix, bud mite, rodents.

Diseases: anthracnose, gray and fruit rots.

Uses: planted for obtaining valuable nuts. Attractive in solitary and group plantings. Can be used for creating hedges and in alley plantings.