The age,  type of tree and location of the forest will all play into the annual offset of the  forest and there is wide discrepancy among experts

On the low end  the EPA estimate

-0.23 metric ton C/acre/year* x (44 units CO2/12 units C) = –0.85 metric ton CO2 sequestered annually by one acre of average forest. Environmental Protection Agency

“A fifty-year-old forest on average absorbs .8 metric tons of carbon per acre per year. A 65 year old forest 1.6 metric tons per acre per year.”  Forest Ecology Network

On the other end  of the scale 

On average, one acre of new forest can sequester about 2.5 tons of carbon annually. Urban forestry Network

We have a little tool below to play around with, to estimate the Carbon footprint of a flight ( it links to a standard offset site)  but just for the purposes of illustration – if we are conservative, 1 acre of forest  should absorb about 1 metric ton of CO2 / year –  3 return European flights e.g. from London to each Frankfurt (0.2), Rome (0.45) and Geneva (0.24) a year (our forests will be older than average). 

At present we are working on the basis of 1 acre of  forest costing about GBP 1,000 and make the commitment that the forest will be maintained for 25 years (we never really plan to cut these down but never sounds a hard promise to make).  So in stark numbers that’s 1,000 pounds offsets 3 European flights a year for 25 years.  

So GBP 1,000 grows an acre of forest  and 

      GBP 10 grows a tree  

But the purpose of this project  was never to surgically dissect our lives into carbon tons and try to exactly offset each action but to make a change in the  right direction  and  so join us  whether it is a tree or 100 ha of  trees to collectively grow forests . 

Grow a tree or a whole forest with us. Grow a