The American or American white walnut is a tree of a size close to 25-30 meters, very long-lived, originating in North America; it is also cultivated for its fruits in Europe, Australia and Africa. There are many dozens of cultivars of this plant, and about twenty species belong to the same genus, most of them originating in North America. It has an erect, majestic bearing, dense and rounded crown; the trunk is powerful, with gray bark, which becomes brown-orange with the passing of the years, covering itself with slight fissures. The leaves are very large, composed, consisting of 11-17 lance-shaped leaves, dark green; if you rub in your hands they give off an unpleasant smell.
In spring the American walnut produces elongated male flowers, and rounded female on long spikes; in autumn it ripens large cylindrical fruits, enclosed in a woody shell, covered by a further fleshy shell, which breaks when ripe; pecan walnut is a very tasty and very appreciated variety all over the world. Generally a carya ovata tree takes at least 10-15 years, or even more, before producing fruit, and many cultivars produce fruit in alternate years.
Speaking of the ideal exposure for the American white or American walnut trees it is advisable to place them in a sunny place; these trees have very slow growth, but it is nevertheless appropriate to evaluate the space necessary for an adequate development of the plant, before planting it.
Generally the specimens of carya ovata do not fear the cold or the heat, but there are cultivars selected specifically for each type of climate; in general they prefer cool climates, with summers that are not too hot and develop more conspicuously with a mild climate.
the American white or pecan walnut trees grow without problems in any soil, but generally they prefer soils with a pH that tends to acid; we recommend burying mature organic fertilizer at the foot of the plant every year, in spring and autumn, or providing a slow release granular fertilizer.
These plants of American genus can however develop in any soil, even in stony and arid soils; it is advisable to supply water to young specimens in the event of long periods of drought.
The majority of pecan plants used for cultivation and subsequent harvesting of fruits is obtained from grafted varieties; if you still want to multiply a carya ovata plant, without the concern of the entity of the future harvest, you can do it using seeds, or taking semi-woody cuttings, in late summer.
American white walnut, American walnut, Pecan nut - Carya ovata: Pests and diseases
This variety of trees is often attacked by aphids and threatening larvae. It is advisable to regularly check whether there are signs of the presence of this type of parasites, so that they can intervene quickly and punctually with the use of targeted anti-parasite products, which will effectively counteract the problem.