Research Report No. 341

Stem deformity in radiata pine on pasture sites in relation to soil properties.  P. Hopmans.  November 1989.  13pp. (unpubl.)

SUMMARY

Stem deformity in P.radiata is recognised as a significant problem in plantations established on land formerly used for agricultural production. While the deformity resembles the visual symptoms associated with copper deficiency, no response has been obtained to copper fertiliser.

A series of plots were established in young P.radiata plantations across a range of former pasture sites to investigate possible relationships between stem deformity, tree nutrient status and soil properties. Results showed that growth and stem deformity varied considerably between pasture sites, with plantations in coastal regions having the lowest level of deformity. In north-eastern Victoria, stem deformity was variable with small numbers of straight trees present even in the worst affected plantations. Estimated losses in yield of merchantable wood ranged from 11% to 63%.

Nutrient status of the plantations was indicative of high soil fertility and foliage concentrations of most nutrients including copper were above levels considered necessary for adequate growth. Stem deformity was positively correlated with levels of phosphorus in the foliage. However, this is not considered to be a causal relationship but is attributed to the high availability of phosphorus in the soil as a result of previous land use and reflects the level of pasture improvement at each site.

Soil properties indicated high soil fertility, especially high availability of nitrogen and phosphorus. Stem deformity was most strongly correlated with nitrogen mineralisation, particularly nitrification in soils. The practical implications of these results are that soil tests estimating potential nitrification in soils can be used to identify pasture sites that are likely to produce P.radiata plantations with a high incidence of stem deformity.

Also published:

Hopmans, P. (1990)  Stem deformity in Pinus radiata plantations in south-eastern Australia.  Plant and Soil 122: 97-104.

Carlyle, J.C., Turvey, N.D., Hopmans, P. and Downes, G.M. (1989)  Stem deformation in Pinus radiata associated with previous land use.  Can. J. For. Res. 19(1): 96-105.