Further studies of Pinus radiata nutrition and growth in the Heywood District.  F.G. Craig.  March 1971.  5 pp. (unpubl.)

SUMMARY

1. Phosphorous deficiency is the major nutritional barrier to successful P. radiata establishment at Heywood, and phosphate fertilizer must be applied at planting on all soil types. A reduced application rate is probably appropriate for the deeper phases of Sherburn loam if these can be delineated successfully.

2. All of the Heywood soils have a high phosphate sorption capacity, but it is not yet clear what proportion of sorbed phosphate is available to P. radiata.

3. For successful establishment and growth, spot applications of 10 ozs. dicalcium phosphate per tree are presently recommended for all soil types except the deeper phases of Sherburn loam. On these, 6 ozs. per tree should be applied. Deep ripping (to 24”) is recommended as a site preparation procedure on all sites and trees should be planted on the mounds beside the ripped lines.