It was gratifying to read in last week’s Gazette of South Gloucestershire’s plans for tree-planting in order to tackle the climate change problems.

In this connection there seems to be very little discussion as to the type of trees that would be most suitable.

It is worth remembering that deciduous trees are without leaves for about half the year, so for all that time no photosynthesis is taking place.

If there is no photosynthesis, no carbon dioxide will be absorbed.

So, during the winter months, when heating systems are pumping out carbon dioxide at their maximum rate, these trees are not doing their job.

This means that conifers are left to fill this gap. I don’t know whether conifers photosynthesise all the year round, or how efficiently they absorb the gas.

Perhaps someone with knowledge of trees could enlighten us.

D. Phillpotts,