C. CH₄ emissions from Enteric Fermentation
The decision tree for estimating methane emissions from enteric fermentation outlines the route that Parties should follow (see Figure 4.2 in the IPCC Good Practice Guidance).

The main features of this decision tree are:

• If there is no domestic animal production in the country, Parties should report “not occurring” (NO).
• If enteric fermentation is not a key category, a basic livestock characterization and Tier 1 method may be applied to estimate emissions from all the animal species. However, it is recommended to apply an enhanced characterization and Tier 2 in all cases provided the Party has the necessary data.
• If enteric fermentation is a key category, then an enhanced livestock characterization and Tier 2 method should be used for the significant animal species. For other species, the use of Tier 2 is recommended if data are available.