How many trees could you plant for $25 million?

Question

Sir Richard Branson et al have offered $25M prize for ways to reduce exisiting greenhouse gases - obvious solution is planting trees - but HOW?

Answer 1

We are a well known company for many years.
we replant trees in containers and let them set for the right period of time.
By this method we establish a great number of trees that we can relocate on a ongoing time.
these trees are harvested in the open bushveld.

Answer 2

My first thought was this as well... but he is obviously looking for a device. Too bad, I was planning on a career as a modern day
Johnny Appleseed.

"Entrants must submit a commercially viable design (the “Design”) to achieve the net removal of significant volumes of anthropogenic, atmospheric greenhouse gases each year for at least 10 years without countervailing harmful effects (the “Removal Target”). The removal achieved by the Design must have long term benefits (measured over say 1,000 years) and must contribute materially to the stability of the Earth’s climate."