Pine Mortality after Planting on Post- Agricultural Lands in South Africa

Successful afforestation has been practiced in South Africa for more than a century. Recently, however, problems with afforestation of pines have occurred in the northeastern part of the Eastern Cape Province. Rapid mortality of Pinus patula and P. elliottii have occurred when small container seedlings were planted on old-agricultural soils. Death would often occur within 5 months of planting. Growth of surviving trees was retarded and new needles were chlorotic and stunted. Acceptable survival was obtained when seedlings were planted on virgin grasslands. Apparently, some unseen factor in the post-agricultural soil reduces root growth, increases mortality, and decreases uptake of nutrients. Removal of the infested soil by scalping greatly improves survival and growth as does soil fumigation with methyl bromide.