2019 Golden Grove programme: Offsetting carbon emissions

“We’re not just raising trees, we’re raising awareness.”


We are pleased to announce an exciting new initiative to explore our goals of sustainability and personal responsibility.

The purpose of the programme is to undertake some practical remediation of that by planting trees, which will be natives or fruit trees.  The difference between this programme and the more nebulous benefits of signing up to an on-line carbon offset scheme, is that we are dealing with actual, real physical trees that you can plant yourself or get us to.

We cannot avoid using some transport in these busy times.  When we use air or car travel, we cause emissions of carbon dioxide, which is a greenhouse gas and therefore adds to climate change.  The carbon dioxide can be absorbed by growing trees.  To put that in perspective, a round trip to the USA requires 4-5 large trees to offset the carbon emissions of one person.

As a classroom exercise we have had the senior pupils to calculate how much carbon dioxide large or small tree trees take up, and therefore how many kilometres of travel it will offset.  This was done under the supervision of Jim Lawless, a scientist with 40 years experience in renewable energy, so we can be confident about the results.

The pupils have produced suitable labels for large, medium and small trees, to be laminated and attached to trees, stating how many km they offset for air or car travel. 

The pupils have already planted a totara tree at the Chapel next to school and we will donate a lemon tree, suitably labelled, to the primary school Te Kura Maori o Waatea in Mangere (where Ailsa, who also helps at Golden Grove, has been establishing food gardens).

We are now ready to offer trees and shrubs to parents and friends of the school.  Each tree will be certified by the school as to its lifetime carbon uptake and hence travel offset.  Depending on the popularity of the programme we may later extend this to the general public.

If you wish to participate but do not have anywhere to plant trees, we can arrange for them to be planted at a suitable location, for a small additional fee.

“Green travel is planting trees to help with the carbon emissions that come from cars, planes, trains and boats. When you drive you cause carbon emissions, so our idea is that if you were to plant a certain amount of trees (depending on where you’re going), say you’re going to Taupo, you would have to plant two trees (the website will tell you what kind) those trees would soak up your carbon emissions.”


“We are planting trees, we see it as a personal responsibility. If you plant a tree, then it will bring you closer to a clean environment for your generations to come.”


“Golden Grove School is planting trees to try and make up for all the carbon emissions we produce. For example our Principal is going to Europe and in order to make up for all that carbon, she has to plant around four trees. I think planting trees is important because if we do not plant trees there will be no future. Golden Grove is offering trees for a better future.”


“Golden Grove are starting a programme called Green Travel. We are doing this programme because every time we travel we cause global warming. We need to do this for our generation so as to save our planet.”


“Golden Grove School is saving trees, the trees can suck up most of [the pollution] from cars and planes and motorbikes … Golden Grove School would love for you to join.”


“Golden Grove School is trying to save our generation and future generations by planting trees… All we want to do is make aware our generation and future generations of what might happen with global warming. We want to try to change the future of global warming, save animal generations and saving human generations from extinction.”


“Golden Grove is starting to help the environment by planting trees because they get rid of pollution. We are getting rid of carbon in the air coming from transport. Tell us if you would like to join us. I will plant 2 trees.”


“What are we doing: planting trees. Why plant trees: Stop climate change.”


“We are planting trees to slow down climate change and clean up our environment because our environment is dying and we need your help to stop climate change. We are also trying to sell trees to make you aware of carbon emissions you make and how to lower them. The trees are not going to be expensive: we are trying to make the trees as cheap as possible. We’re not just raising trees, we’re raising awareness.”


In case you are interested we have used the following assumptions when calculating the travel-km offset:

  • Air travel is by Economy class, long haul flights.  Shorter flights would produce more emissions per km, as planes use a lot of fuel on take-off.  First class travel produces more, because there are less people per plane and more luggage and more flight attendants.
  • Car fuel usage is for a typical medium-sized car in NZ, with one passenger.  If there are more than one passenger, then the amount per passenger would be less.  Large cars use more.  Hybrids use less, and electric cars produce almost zero emissions.
  • Trees are allowed to grow for 40 years.  If they die or are cut down sooner they will have to be replaced.  If they live longer they will take up more carbon dioxide, but old trees slow down their growth so it is not in proportion to their age.  Shrubs are assumed to live for 30 years.
  • To estimate how much carbon dioxide from air travel, we will use the method found at: https://co2.myclimate.org/en/flight_calculators/new
  • To estimate how much carbon dioxide trees absorb, we will use the method found at: https://projects.ncsu.edu/project/treesofstrength/treefact.htm
  • A large tree (20m or more tall ), such as totara, kauri or rimu is assumed to take up three times as much carbon dioxide as a medium to small tree (up to 10m tall), such as manuka, olive or fruit trees, and 10 times as much as shrubs (up to 5 m tall) such as camellias or small fruit trees.