You can't eat trees.

That line came from the mouth of Nationals Senator Fiona Nash yesterday.

She was arguing for the notion that existing vegetation on farmland should be protected, preferring instead a regime which permits farmers to clear vegetation on their land for crops or grazing.

Carbon sinks appear to me to be a good idea. Individuals and businesses would be able to invest in such carbon sinks to offset their carbon emissions, the more they emit, the more trees planted on their behalf to suck the excess CO2 out of the atmosphere.

The Nationals, as evidenced by the comments of Senator Nash and others, don’t like this. They seem to believe that farmers should be allowed to clear their land at whim for cows and sheep and wheat. Barnaby Joyce is travelling today to country New South Wales to visit a farmer who is hunger-striking until such time as he is permitted to clear his land. Food security is, according to Fiona, the most pressing issue facing Australia.

Perhaps, Senator Nash. But part of the reason your farmer constituents find it so difficult to maintain the same levels of food production these days is because it doesn’t rain as much.

It doesn’t rain as much because of el Niño’s increased ferocity and frequency due to global warming.

And a big part of the global warming problem is that we’ve felled far too many trees, compounding the carbon dioxide problem. We’re pumping more CO2 into the atmosphere than ever before, while at the same time removing the gas’ most reliable filter.

I grant you Senator, that trees cannot be eaten.

But neither, Senator, can we ‘breathe’ this much carbon dioxide.