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Calculating carbon in the ETS
In the ETS, you must be able to calculate how much carbon is in your forest land. This is so you can report on changes in the amount of carbon in emissions returns.
You must submit an emissions return at the end of every mandatory emissions return period. You may be required to also submit emissions returns at other times.
Find out more about when you need to submit emissions returns
Find out more about mandatory emissions return periods
Carbon tables for calculating carbon
To calculate the carbon in your forest land, you need to use carbon tables. There are 2 types of carbon tables:
- standard carbon tables, also known as "default tables"
- carbon tables made specifically for you, known as "participant-specific tables".
To work out whether you need participant-specific tables, read the next section below.
To get participant-specific tables, you need to collect measurements of your forest at sample plots allocated by us. This is known as the "Field Measurement Approach" (FMA). There are some rules around requesting sample plots and collecting measurements. These are explained below.
What happens if you have 100 hectares or more of post-1989 forest land
If you will have 100 hectares or more of post-1989 forest land at the end of the mandatory emissions return period, you must request permanent sample plot locations for all your registered forest land. Once we allocate these plot locations, you must collect measurements at these points (known as sample plots) and have participant-specific tables made for you by MPI. You must use these tables for the emissions return at the end of the mandatory emissions return period.
How to request sample plot locations
If your registered post-1989 forest land has reduced to less than 100 hectares but you still have 2 or more sample plots (or 2 or more sample plots in each forest class, if you have both forest classes assigned) allocated at the end of the mandatory emissions return period, you don’t need to request sample plot allocations for all of your forest land. You still need to collect measurements at your existing plots and have participant-specific tables made for you by MPI. You must use these tables for the emissions return at the end of the mandatory emissions return period.
Note: If you reduced your registered land to less than 100 hectares and never had sample plots allocated, use the standard carbon tables.
Sample plots for exotic and indigenous forest land
As part of the process to get participant-specific tables, you may choose to class areas of your forest land as "exotic" and "indigenous". If you do this, you only need to collect measurements at your sample plots and have participant-specific tables made for you if you have 2 or more active sample plots on each of those areas.
Inactive sample plots
At certain times your sample plots may be "inactive". If you do not have 2 or more active sample plots at the end of the mandatory emissions return period, you do not need to use participant-specific tables. Instead, you need to use the standard carbon tables.
Find out when sample plots are inactive
Hiring someone to measure your forest
Measuring your forest is complicated and takes time. You may want to work with a forest inventory provider for the FMA. You can also appoint a representative to help you manage your ETS tasks.
Find out more about appointing a representative
Getting participant-specific tables
There are 5 main steps to complete before we issue your participant-specific tables. The steps are:
- Classify your forest land as exotic or indigenous (optional).
- Request sample plot locations.
- Establish sample plots on your forest land.
- Collect forest information at your sample plots.
- Submit your forest information to us.
Find out how to request sample plot locations in section 10.4.2 of the user guide for Tupu-ake, the ETS online system:
User guide for Tupu-ake [PDF, 15 MB]
There are fees for parts of this process where we provide a service.
Find out the current fees for forestry in the ETS
There are some decisions to make before you start. Details of these and how to complete each step are explained in the guide to the Field Measurement Approach.
Guide to the Field Measurement Approach [PDF, 2.9 MB]
The rules for this process and how to submit your information are set by the Field Measurement Approach Standard and the Field Measurement Approach Information Standard.
Field Measurement Approach Standard [PDF, 524 KB]
Field Measurement Approach Information Standard [PDF, 724 KB]
You must submit your forest information through the Climate Change Information System (CCIS). Instructions for how to submit your forest information are available in the user guide below.
Field Measurement Approach CCIS user guide [PDF, 1.6 MB]
When to measure sample plots
If you need to use participant-specific tables for the emissions return at the end of the mandatory emissions return period, you must make sure they are “definitive”. Participant-specific tables are definitive if, at the end of the mandatory emissions return period:
- the plot set measured to create the tables reflects your current ETS landholding, and
- the information about silviculture and any natural events affecting the land used when creating the tables is still correct.
You need to:
- measure your sample plots before the end of the mandatory emissions return period
- submit the information with enough time for us to create your tables and for you to submit your emissions return.
This emissions return must be submitted between 1 January and 30 June of the year following the end of the mandatory emissions return period.
You may collect and send us information from your sample plots more often, and we will create new tables for you.
When sample plots are inactive
At certain times, sample plots are inactive. You don’t need to measure inactive sample plots. Plots are inactive when the carbon accounting area containing the plot:
- is registered under averaging accounting, in certain situations (explained below)
- is being used to offset the emissions of removing another area of post-1989 forest land from the ETS
- is temporarily damaged by a natural or accidental event (temporary adverse event)
- has an approved temporary waiver.
Find out about offsetting post-1989 forest land
Find out about temporary damage to post-1989 forest land
For averaging accounting
Sample plots are inactive when they are in a carbon accounting area registered under averaging accounting, and the whole carbon accounting area reached the average age for its forest type:
- before the mandatory emissions return period started, if the area was created through registering the forest land in the ETS
- before the mandatory emissions return period started, if the area is on a second or later rotation for the whole mandatory emissions return period and was created through registering the forest land in the ETS
- before the carbon accounting area was created, if it was created another way. For example, by transferring or removing part of the land, changing to permanent forestry, or through a temporary adverse event suspension.
Find out about averaging accounting
Carbon tables to use for other emissions returns
You may need to submit emissions returns at other times, for example, after a change in land ownership. You only need definitive participant-specific tables for the emissions return you submit at the end of a mandatory emissions return period. Until you get new tables for the period, you must use your most recent tables for any other emissions return. If you don’t have any yet, you must use the default tables.
Default tables of carbon stock per hectare for post-1989 forest land – NZ Legislation
Find out when you need to submit emissions returns
Change in forest species
Forests can have trees of different species mixed in together, and sometimes the main (or “predominant”) species can change over time. If this happens and you are using participant-specific tables, your existing tables may no longer accurately represent the carbon stock in your forest.
Your new forest measurements record any changes in the amount of carbon stored in the forest. In an area where the main species has changed, your forest measurements will reflect this only if:
- your plot locations represent the whole forest area
- all of the main forest species are measured
- enough plots contain the main species which changed.
If you need more information about how a change in the main species of your forest may affect you or your carbon calculations:
- email forestryETS@mpi.govt.nz
- call 0800 CLIMATE (0800 25 46 28 and select option 1).
If you are unable to collect and submit your forest information
If you are unable to or don’t have enough time to collect your information before the end of a mandatory emissions return period, you can:
- apply for more time to submit your forest information, or
- apply for a temporary waiver.
You may apply for a permanent waiver if it is too dangerous or difficult to establish or measure one of your sample plots.