Survival and early growth of radiata pine seedlings following root puddling in hydrogel slurries.  G. Minko.  February 1988.  11pp. (unpubl.)

SUMMARY

The treatment of radiata pine seedlings from the time of lifting in the nursery to field planting is known to strongly influence their outplanting performance. A common nursery practice is to wash roots in water prior to despatch.

A study was undertaken in north-eastern Victoria to compare survival and early growth of radiata pine transplants whose roots were washed and watered according to routine nursery procedures with those whose roots were puddled in either of two hydrogel slurries. Puddling of roots in either of the slurries was found to significantly reduce mortality and increase early height and diameter growth of transplants at planting sites in the Bright, Beechworth, Koetong and Myrtleford plantations. For example, mortality of transplants whose roots were washed with water was found to be 57%, 32% and 23% at Beechworth, Bright and Koetong respectively, whereas puddling in a hydrogel slurry reduced mortality to 4%, 8% and 4% at the respective localities.

It is recommended that the current nursery practice for treatment of seedling roots be replaced by puddling the roots in a hydrogel slurry. The cereal-based, bio-degradable hydrogel tested in the present study is preferred.