From little acorns ...

A technique to accelerate the growth of oak trees in Northern Ireland has been developed by CAFRE (College of Agriculture, Food and Rural Enterprise) Greenmount Campus in conjunction with AFBI (Agriculture, Food and Bioscience Institute) Loughgall.

These techniques will be highlighted at a meeting on Accelerated Plant Production Technologies on Tuesday 7 November 2006 at Greenmount Campus starting at 7.15 pm. Three speakers will focus on techniques to improve growth rates and plant development in hardy ornamental and tree species.

The technique adopts the principle of allowing air to prune roots (termed air-root pruning) of young seedlings at germination and in the seedling stages. Air root pruning results in more new and active roots produced to absorb more nutrients thereby accelerating the growth of the seedlings. When these oak seedlings were transplanted nine months later (in 2001) the growth was rapid. The trees reach an average height of 3.5 metres (with some reaching 4.5 metres) within five years after transplanting. Oak trees from the traditional bare roots were much slower growing, reaching a height of 2.5 metres and only half the girth of the root-pruned trees. The above ground biomass (an indicator of the total size of the trees) of air-pruned oak trees at four years is double that of bare root transplants.

According to Gerry Hoppé, Senior Scientific Officer from AFBI, Loughgall,

“We have been monitoring these trees for the past five years, measuring tree and root growths and found that the differences were phenomenal. These air pruned oaks also produced earlier acorns, for breeding and selection of oak trees of local origins”.

According to Dr. Raja Harun, Senior Horticulture Technologist from CAFRE, Greenmount Campus, who started the project in March 2000.

“The technique of air root pruning works with various tree species and also with ornamental shrubs. For the past three years we have been adapting the technique to produce high value ornamental species such as Cedrus, Hollies, Phormium. These species grow at twice the rate of plants produced using standard methods halving the time in the nursery, and they can therefore be marketed at a much earlier stage”.

For those wishing to attend please contact David Kerr (028 3751 5645 or mobile 078 9986 4343).

Dr Raja Harun (Senior Horticulture Technologist, College of Agriculture, Food and Rural Enterprise, Greenmount Campus) beside an oak tree transplanted in 2001 produced using a root pruning technique.