Ash dieback

JE Pratt is correct to be 
concerned for the long-term future of our ash trees because of chalara (ash dieback disease) and to call for a re-assessment of present government policy 
(Letters, 2 March).

That policy depends upon the Micawberish hope that some ash trees will turn up that are resistant to chalara. But, even if ash does prove sufficiently genetically diverse to allow a few trees to survive, much of that genetic diversity will be destroyed by chalara as it kills off those ash – apparently the great majority – without such resistance.

Moreover, another killer of ash trees, the emerald ash borer beetle, is spreading from its home range in east Asia at 25 miles per year, and has reached Moscow.

Under present policy, the genetic diversity of ash trees seems almost certain to be irredeemably lost.

Yet that diversity is still present and could be preserved if ash seeds from representative populations were stored in the 
Svalbard “doomsday” vault that already stores global food crop seeds and has recently received its first seeds from tree species,
namely Scots pine and Norway spruce.

If that were done then future generations could restore genetically diverse ash trees if scientific advances allowed chalara and ash borer to be overcome.

If we do nothing then those future generations’ only option would be to curse us for our penny-pinching lack of vision.

Roy Turnbull

Nethy Bridge

Inverness-shire