You reap what you sow, so this may be the most appropriate suggestion to humans who are looking into saving the world. More seeds may need to be planted to save the planet from total destruction. 

A recent study echoes exactly this: more trees need to be planted because it is the most effective way to save the planet from climate change. If an area as huge as the US will be covered with trees, the research reveals that the greenery could eliminate ⅔ of all human-based  carbon dioxide in the atmosphere. 

The results of the study were published in the journal Science. A team of researchers from the Crowther Lab in Switzerland mapped and identified all the land on Earth that could feasibly support a forest. Then, they subtracted it from the total land area for both urban and agricultural practices, not to mention the existence of forests in the world. 

According to the results of the study, nearly a billion hectares of land can be covered in trees. The vast reforestation would dramatically increase the forest land of the Earth by a third than what exists today. And because naturally are carbon dioxide absorbers, having additional forests could indeed reduce the amount of carbon dioxide concentration in the atmosphere. 

'If people acted on it now, it could reduce carbon dioxide in the atmosphere by as much as 25%. It may be able to reach the levels that it was centuries ago," said Tom Crowther, a senior member of the team who did the study. 

The authors also believe that the results of their study could be the research groundwork that will require a global action plan. Is it possible for people to build a forest from scratch? More than 50% of the land area available for new forests are located in Canada, Australia, China, Brazil and Russia. The study also includes the analysis of the forest ecosystems to identify the trees they need to cover the area as well as the amount of carbon dioxide they could absorb. 

Overall, the authors of the study were able to identify reforestation areas and the fact that if they were all covered with trees, they could produce 205 metric gigatons of carbon. That could be very challenging to achieve though as many trees take a lot of time to grow, restore soil and encourage plant growth. It is not just about growing trees, but also about attracting wildlife to create a diversity of species that live on the same land area. 

"It will take decades for new forests to mature and achieve all the potential that it comes with. The better thing to do is to protect the forests that is in existence, pursue solutions for climate change and work on phasing out fossil fuels," Crowther said.