The black walnut tree, with the scientific name of Juglans nigra, was introduced to Europe in the mid-1600s, but it has not spread beyond America and Europe. It grows mostly in riparian zones, from southern Ontario, west to southeast South Dakota, south to Georgia, northern Florida and southwest to central Texas. Wild trees in the upper Ottawa Valley may be an isolated native population or may have derived from planted trees. Black walnuts are popular food sources in both America and Europe, and can be found in everything from candy, ice cream, fudge, and salads, as well as chicken, pork, and pasta dishes. Most parts of the tree including leaves, stems, and fruit husks have a very characteristic pungent or spicy odor. Fruiting may begin when the tree is 4–6 years old; however large crops take 20 years. A green rounded husk, 1½-2½ inches across, covers the round, hard, bony, dark brown or black nut. The kernel is oily, sweet, and edible.
| Name | Black walnut |
|---|---|
| Scientific Name | Juglans nigra |
| Native | Native to the eastern United States, as well as certain parts of Southern Canada. |
| Common/English Name | Black walnut, American walnut, eastern black walnut, carya, carya basilike, carya persica, green black walnut, green walnut, juglans nigra, jupiter’s nuts, nogal americano, nogal negro, nogueira-preta, noix, noix de jupiter, noix de perse, noix verte, noyer d’amérique, noyer noir, noyer noir américain, nux persica, nux regia, schwarze walnuss, walnoot, and walnut |
| Name in Other Languages | Chinese: Hei hu tao (黑胡桃), Hei he tao (黑核桃) Croatian: Crni orah Czech: Ořešák černý Danish: Amerikansk sort valnød, Sort valnød Dutch: Amerikaanse zwarte walnoot, Zwarte walnoot English: American black walnut, Black walnut, Eastern Black Walnut, Noyer noir Finnish: Mustajalopähkinä French: Noyer noir, Noyer noir d’Amérique du Nord German: Amerikanischer Nußbaum, Schwarznuß baum, Schwarze Walnuß, Schwarzer Walnußbaum Italian: Legno di noce nero d’America Japanese: Burakkuuooru nattsu (ブラックウォールナッツ) Portuguese: Nogueira-preta Romanian: Nuc american Russian: Chernyi orekh (Черный орех) Slovakian: Orech čierny Spanish: Nogal americano, Nogal negro, Nogal negro americano Swedish : Svart valnöt |
| Plant Growth Habit | Large deciduous hardwood tree |
| Growing Climate | Found growing along roadsides, fields, and forest edges in the eastern US. It will grow in closed forests, but is classified as shade intolerant; this means it requires full sun for optimal growth and nut production. |
| Soil | Require a deep, fertile soil with a near-neutral or slightly acidic pH. It also tolerates relatively dry, poor soils, but with a significantly reduced growth rate. |
| Plant Size | 70 feet tall by 70 feet wide |
| Root | Deep & strong taproot as long as 10 feet |
| Bark | Typically grey-black and deeply furrowed into thin ridges which gives the bark a diamond shaped pattern |
| Trunk | Tall trunk Under forest competition, it develops a tall and straight trunk. When grown in an open area it has a short trunk and broad crown. |
| Leaf | Leaves alternate, compound, 1–2 feet long, with 11–23 leaflets. Leaflets 3–5 inches long, 1–2 inches wide, broadest below the middle, the end leaflet smaller than side ones or absent; margin toothed; upper surface yellow-green; lower surface paler, hairy. The leaves are overall dark green in color and are typically hairy on the underside. |
| Flowering Season | April–May |
| Flower | Monoecious. The male (staminate) flowers are in drooping catkins 8–10 cm (3 1⁄4–4 in) long. These are borne from axilary buds on the previous year’s growth. The female (pistillate) flowers are terminal, in clusters of two to five on the current year’s growth. |
| Fruit Shape & Size | Small nut with a brownish-green, semi fleshy husk and a brown, corrugated nut. About two inches in diameter and are shaped like basketballs. |
| Fruit Color | Green when immature, and yellow-black when ripe |
| Flavor/Aroma | Robust, distinctive, natural flavor |
| Season | September–October |
| Major Nutrition | Total Fat (lipid) 74.16 g (211.89%) Manganese, Mn 4.87 mg (211.74%) Copper, Cu 1.7 mg (188.89%) Phosphorus, P 641 mg (91.57%) Tryptophan 0.398 g (90.45%) Valine 1.589 g (75.24%) Isoleucine 1.208 g (72.25%) Histidine 0.84 g (68.18%) Protein 30.08 g (60.16%) Magnesium, Mg 251 mg (59.76%) Leucine 2.105 g (56.95%) Vitamin B6 (Pyridoxine) 0.729 mg (56.08%) Threonine 0.901 g (51.19%) Iron, Fe 3.9 mg (48.75%) Vitamin B5 (Pantothenic acid) 2.075 mg (41.50%) Selenium, Se 21.2 µg (38.55%) Zinc, Zn 4.21 mg (38.27%) Lysine 0.891 g (26.64%) Total dietary Fiber 8.5 g (22.37%) Vitamin E (alpha-tocopherol) 2.6 mg (17.33%) Potassium, K 654 mg (13.91%) Vitamin B2 (Riboflavin) 0.162 mg (12.46%) |
| Health Benefits |
|
| Calories in 1 cup (125 gm) | 774 K cal |