Not so much an image, but a table showing the decline in world forests:
Some interesting trends: Europe has seen a steady reforestation, while in South America and Africa has seen the largest declines.
The trends are many: drought, wildfires, forestry management practices, new plantations etc.
There is of course the question of biodiversity.
Sure, more trees are good – but maintaining unique and fragile ecosystems is also worth fighting for.
They provide vital ecosystem services.