Carbon dioxide is a constant target of climate change measures, yet, one of the first things we are taught in science class at school is that plants like CO2, so aren't they loving the abundant gas?

It’s simple biology, plants take in CO2 and release oxygen through photosynthesis. Since carbon has existed for millennia and plant life has survived because of it you might think that more carbon dioxide in the atmosphere means better growth for the plants on the ground.

To a certain point this is true, studies show that crops grown within controlled environments with extra CO2 do grow faster and in greater abundance. But when crops in open fields are supplied with extra CO2 the theory falls apart.

The issue lays in the plants’ other requirements. Water, nitrogen, and nutrients. With fossil fuel usage pumping additional CO2 into the environment the balance of these resources falls askew.

Plants contain more carbon and less nitrogen for example, meaning insects are more likely to eat them to get their own nutrition.

So this is one myth that has a hazy answer. Yes, in a controlled environment plants can benefit from additional CO2, but in open fields they suffer.