There is a high demand for hardwood timber, such as hybrid walnut, in the EU. These trees are often grown within an intensive management system and short rotations - comprising irrigation, fertilisation, chemical weed control, causing high economic and environmental costs. Introducing livestock and sowing legumes can reduce the financial costs of these plantations and optimise their environmental functions.



Tips:

• Hybrid walnut trees need a rather humid climate, preferably with a moderate dry period (about 3 months without rains) and not too cold (annual mean temperature above 10°C).

• Walnut trees prefer a deep, well-drained soil, with a loamy texture and neutral or slightly basic pH.

• Trees should be planted at a density of 333 trees/ha (5x6 m) and when planting 1-2 year-old trees, saplings should be around 60-100 cm height.

• The trees are very sensitive to weed competition during the first 5 years.

• Irrigation is needed if summer drought occurs.

• A stocking rate of 1-2 sheep/ha is recommended in the Mediterranean regions. With summer and winter fodder supplementation livestock can remain in the plantations all year round.

• Trampling damage should be avoided by using tree protection guards during the first 5-6 years.

• Sowing legumes as an alternative to applying mineral fertilisers increases available nutrients in the soil (especially N), improves pasture production and quality, and optimises the environmental functions of plantations. Use self-seeding legumes which can tolerate grazing and shade for this purpose!

• Grazing under walnut plantations reduces fire risk, competition between trees and weeds and the financial costs for controlling competition (mowing, herbicides).