Nutrition of Douglas-fir in four different regions of the Czech Republic.
Soil properties and foliar chemistry of Douglas-fir stands were evaluated in four regions with historical cultivation of this introduced species in the Czech Republic. All the localities are on acidic sites with pH (KCl) ranging between 4 and 5, low in concentrations of base cations particularly at the soil depth between 10 and 40 cm and also low in phosphorus. Sufficient to increased content of nitrogen and, on the other hand, the deficiency of phosphorus, potassium and occasional deficiency of magnesium were found in foliage. Studied Douglas-fir stands are apparently proximate to the acidic limit of convenient site conditions, however, neither the foliage discoloration nor the growth suppression has been observed. Sensitive management to ensure the nutritional balance sustainability is proposed.