A green husk surrounds the nut of the English Walnut. The husk naturally splits at the time of ripening to release the nut
The Persian walnut, so named to indicate its place of origin, is the most popular walnut, grown in many parts of the world. It was used as a source of food on the ancient trade routes across Asia and so became established in China in the east and Europe in the west. From Europe, it spread westward to North and South America as well as Australia as the "New World" was unfolded.. It is most commonly called "English" walnut, but it is also known by other names such as "Carpathian" walnut, and "California" walnut. Persian walnuts will grow in a range of well drained soils from sand to clay loam. The pH should be between 6 and 7. They grow to 15 m tall and spread about 10 to 15 m as they mature. Grafted trees will begin to bear in 3-4 years while seedling trees can take 5 years or more. Generally, seedlings from good selections are productive, reasonably thin shelled and good quality, but to be sure of quality, filling, and production, the grafted tree is superior.
Scientific classification Species Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Fagales Family: Juglandaceae Genus: Juglans L.
<ul><li>Species and classification </li></ul><ul><li>Sect. Juglans . Leaves large (20-45 cm) with 5-9 broad leaflets, hairless , margins entire. Wood hard. Southeast Europe to central Asia . </li></ul><ul><ul><li>Juglans regia L. ( J. duclouxiana Dode, J. fallax Dode, J. orientis Dode) - Persian Walnut , Carpathian, or Common Walnut </li></ul></ul><ul><ul><li>Juglans sigillata Dode - Iron Walnut (doubtfully distinct from J. regia ) </li></ul></ul><ul><li>Sect. Rhysocaryon . Leaves large (20-50 cm) with 11-23 slender leaflets, finely pubescent, margins serrated. Wood hard. North America , South America . </li></ul><ul><ul><li>Juglans australis Griseb. ( J. boliviana Dode) - Argentine Walnut </li></ul></ul><ul><ul><li>Juglans brasiliensis Dode - Brazilian Walnut </li></ul></ul><ul><ul><li>Juglans californica S.Wats. - California Walnut </li></ul></ul><ul><ul><li>Juglans hindsii (Jepson) R.E.Smith - Hinds' Walnut </li></ul></ul><ul><ul><li>Juglans hirsuta Manning - Nuevo Leon Walnut </li></ul></ul><ul><ul><li>Juglans jamaicensis C.DC. ( J. insularis Griseb.) - West Indies Walnut </li></ul></ul><ul><ul><li>Juglans major (Torrey) Heller ( J. arizonica Dode, J. elaeopyron Dode, J. torreyi Dode) - Arizona Walnut </li></ul></ul><ul><ul><ul><li>Juglans major var. glabrata Manning </li></ul></ul></ul><ul><ul><li>Juglans microcarpa Berlandier ( J. rupestris Engelm.) - Texas Walnut or Little Walnut </li></ul></ul><ul><ul><ul><li>Juglans microcarpa var. stewartii (Johnston) Manning </li></ul></ul></ul><ul><ul><li>Juglans mollis Engelm. - Mexican Walnut </li></ul></ul><ul><ul><li>Juglans neotropica Diels ( J. honorei Dode) - Andean Walnut </li></ul></ul><ul><ul><li>Juglans nigra L. - Black Walnut </li></ul></ul><ul><ul><li>Juglans olanchana Standl. & L.O.Williams - </li></ul></ul><ul><ul><li>Juglans peruviana Dode - Peruvian Walnut </li></ul></ul><ul><ul><li>Juglans soratensis Manning - </li></ul></ul><ul><ul><li>Juglans steyermarkii Manning - Guatemalan Walnut </li></ul></ul><ul><ul><li>Juglans venezuelensis Manning - Venezuela Walnut </li></ul></ul><ul><li>Sect. Cardiocaryon . Leaves very large (40-90 cm) with 11-19 broad leaflets, softly downy, margins serrated. Wood soft. Northeast Asia , eastern North America . </li></ul><ul><ul><li>Juglans ailantifolia Carr. ( J. cordiformis Maxim., J. sieboldiana Maxim.) - Japanese Walnut </li></ul></ul><ul><ul><li>Juglans cinerea L. - Butternut </li></ul></ul><ul><ul><li>Juglans mandshurica Maxim. ( J. cathayensis Dode, J. formosana Hayata, J. hopeiensis Dode, J. stenocarpa Maxim.) - Manchurian Walnut or Chinese Walnut. </li></ul></ul>
Climate Walnut is sensitive to low temperature during spring and high temperature during summer.Early frosts also injure young shoots causing them to fail to leaf out in the ensuing spring. At bloom, temperature of even 2°–3°C below freezing results in killing of a large number of young flowers. Hot summers with low humidity result in blank nuts. They grow well in areas with well-spread rain of about 75cm or more. Temperature of 29°–32°C near harvesting results in well-filled kernels. Areas where the trees do not receive adequate chilling cause them to leaf out and bloom late.
Training and pruning Modified central leader system is most ideal for training since it provides very good strength to its framework. Trees should be trained on a single stem up to 1–2m, on which 5–6 scaffold branches should be retained at almost uniform distance spirally. Excess buds should be pinched during first year. Pruning is not being practised in our country, as almost entire plantation is of seedling origin, attaining giant size which makes pruning in later years almost impossible. However with grafted plants, pruning is practicable which can help increase the productivity and improve the quality. Trees of seedling origin receive some kind of pruning while harvesting by thrashing the limbs with wooden poles. It is however a crude method which needs to be modified.
Persian Walnut Planting Plan Tree spacing 28' x 28' x 40' in a triangular pattern. Area = 1.1 Acres or 0.45 ha. Gl, G2 and G3 are 3 different grafted cultivars totaling 60 trees FUTURE FOLLOW UP When trees crowd, remove the 30 trees in the even numbered walnut rows. Good trees can be tree spaded into a new planting that will begin to bear in a few short years. Gl should be a prolific variety like Lake to maximize the early year production
Walnut, English Nutritional value per 100 g (3.5 oz) Energy 660 kcal 2740 kJ Percentages are relative to US recommendations for adults. Source: USDA Nutrient database Carbohydrates 13.71 g - Sugars 2.61 g - Dietary fiber 6.7 g Fat 65.21 g Protein 15.23g Thiamin (Vit. B1) 0.341 mg 26% Riboflavin (Vit. B2) 0.150 mg 10% Niacin (Vit. B3) 1.125 mg 8% Pantothenic acid (B5) 0.570 mg 11% Vitamin B6 0.537 mg 41% Folate (Vit. B9) 98 μg 25% Vitamin C 1.3 mg 2% Calcium 98 mg 10% Iron 2.91 mg 23% Magnesium 158 mg 43% Phosphorus 346 mg 49% Potassium 441 mg 9% Zinc 3.09 mg 31% Manganese 3.414 mg Selenium 4.9 mg
Inside of a Persian Walnut nut with green outer layer visible in the top left corner
The shell of the English walnut is light brown, hard, and bumpy. It is roughly oval and tapers at the bottom. The shell has an vertical seam dividing it into two halves.
Walnut meats have a lobed and wrinkled appearance. The outside is golden brown and the inside white to light brown. Inside each shell are two nuts, separated by a thin, paper-like layer. Each nut meat resembles a butterfly or wings, with two flared lobes joined by a smaller center section. Walnuts can be confused with pecans, but pecans look more like a brain than wings
A Kyushu University (Japan) clinical study published in the July 2002 issue of the European Journal of Clinical Nutrition, shows that walnuts make a healthy diet even healthier. Kyushu University researchers concluded that, an Asian diet that includes moderate quantities of walnuts (1/4-1/3 cup), without an overall increase in total dietary fat and energy, lowers serum cholesterol concentration and favorably modifies the serum lipoprotein and fatty acid profile in normal Japanese women and men, without influencing the LDL oxidizability. LDL "bad" cholesterol was lowered by 8.9 percent in men and 10.6 percent in women. Total cholesterol was lowered by 3.8 percent in men and 4.9 percent in women. There was no significant change in HDL "good" cholesterol. The results suggest that alpha-linolenic acid in the walnut diet appears to be responsible for lowering LDL cholesterol, particularly in women. The Kyushu study concludes a series of three clinical trials testing the effect of walnuts in cholesterol-lowering Western, Mediterranean and Asian diets. The results show that walnuts improve the three major diet styles, lowering bad cholesterol significantly in every instance. These studies, in combination with a growing body of other clinical research, show walnuts to be a powerful nutrition package. About Walnuts - Walnuts are unique among nuts because the "good" fat they contain is primarily polyunsaturated, the source of omega-3 essential fatty acids. Mounting scientific evidence suggests that omega-3s lower cholesterol and protect the heart . One of the oldest foods, walnuts today are recognized for their flavor, versatility and health benefits
English walnut trees grow 40 to 60 feet in height and width and have an rounded to spreading shape to their canopy.
English walnut leaves are compound and arranged alternately along the stem
The leaf is composed of 5 to 9 leaflets, each reaching a length of 2 to 5 inches.
English walnut and Black walnut differ in the number of leaflets, the shape of the leaflets, and the leaflet margin. black walnut leaves have a greater number of leaflets (15-23) than English walnuts (5-9). English walnut leaflets have more oval shaped leaves while black walnut leaves are generally smaller and narrower in shape. Black Walnut leaflets have toothed margins while English walnut leaflet margins are entire.
English walnut and Butternut have the same general leaf shape. They differ in the number of leaflets, butternut has 11-19 leaflets, while English walnut has only 5-9. Also, butternut has a toothed margin, while the leaf margin of the English walnut is entire.
Black walnut fruit is usually between two and three inches in diameter. The husk (shown here) is rough and light green in color and forms the outer layer of protection for the nut
Black walnuts grow in clusters amidst the pinnately compound leaves
Harvesting and Postharvest management Walnuts are usually harvested when hull colour changes from green to yellowish with cracks or when splitting starts at suture from pedicel end. Nuts should be harvested at PTB stage (when packing tissue turns brown). For better nut recovery, the orchard floor should be cleaned and tarpaulin or polythene sheets may be spread on the floor beneath trees prior to knocking of the nuts. After harvesting, nuts should be properly dehulled, washed and dried. In case nuts are not dried properly there is every apprehension of mould development which impairs the quality of the fruit. In Himachal Pradesh harvesting commences from August and extends up to last week of September, whereas in Kashmir walnuts are harvested in September.
The shell is brown and wrinkled in appearance and and is the second layer of protection for the nut. The nut is found inside the shell.
Black walnut trees are very large, ranging from 50 to 75 feet in height and width.
Walnut shoot cut longitudinally to show chambered pith . Scale in mm
Black walnut kernels are often used in the manufacturing of ice cream, commercial baking, and candy making