How many years ago was the land cover different?

As modern studies of the fossil remains of ancient plants show, due to climate changes on our planet, the type of dominant vegetation has changed many times. For example, in the Carboniferous period, which was on the planet about 350-290 million years ago, rainforests existed almost everywhere. However, they were very different from modern ones. In this period, flowering plants had not yet formed, and the forests consisted of tree ferns, lycopods, cycads and horsetails.