Production Practices and Quality Assessment of Food Crops. Vol. 1

Chestnut, an Ancient Crop with Future 139
Figure 15. Irrigated orchard in North Portugal.
Table 13. Macro- and micronutrients in leaves related to dry matter (Breisch,
1995).
Element Concentration
Nitrogen 1.8–2.5%
Potassium .06–10‰
Calcium 0.8–12‰
Magnesium 0.2–4‰
Phosphorus 0.3–4‰
Manganese 0.3–1‰
Copper .10–15 ppm
Iron .60–100 ppm
Zinc .25–35 ppm
Boron .40–50 ppm
necessary. Although nut production is delayed and reduced considerably, quality
of the nuts is maintained (Pereira-Lorenzo and Fernandez-Lopez, 1995).
(2) New systems proposed for chestnut are the Japanese pruning, central leader
and laterals in a plain (Breisch, 1995). Japanese pruning is an easy way to train
chestnut tree to a globlet shape where the branches come from the base of the
trunk. It allows a fast bearing, an easy pruning tree. The central leader is to promote
a main axe while the lateral branches appear along in avoiding a heavy competition
by removing the ones too close the others. Using a plain trellis, lateral branches
of the central leader can be orientated in a direction to facilitate harvesting.