Severe growth disorders were observed in Pinus radiata and P. pinaster in Central Chile. The affected trees appeared bushy and were stunted in their growth due to repeated dieback of the leading shoots. Soil applications of 25 grams borax per tree eliminated this dieback of the shoots and increased growth of the affected trees substantially, thus proving that the phenomenon was caused by boron deficiency. In a survey of Central Chile, boron deficiency in pines was detected in the foot hills of The Andes, in the Central Valley as well as in the coastal mountains. The most severe cases of boron deficiency were observed in and along the erosion gullies el the coastal mountains.
1 Ph. D., Fitopatólogo, Profesor extraordinario, Facultad de Agronomía, Universidad de Concepción, Chillán