This part of the application allows you to define the section of the tree stem for which you want to calculate volume.

For each volume output, you must select how to define the top and base of the section. There are several options for top and base definition:

• Height (meters) - defines the top or base of the section by height in meters.
• Percentage of tree height - defines the top or base of the section by % of total tree height.
• Diameter (cm) - Top or base defined by diameter in cm.
• Percentage of tree DBH - Base defined by % of tree DBH (note – this option can only be used to define the base diameter of the stem section).

The attributes (stem sections) you define can be used for volume calculation. You can select which attributes you want to calculate by using the checkbox next to each of the volume attributes. If you try to calculate volume without selecting any volume attributes, volume will be calculated for every volume attribute that is currently defined.

Your defined volume attributes are saved on the server and bound to your browser. If you want to make a backup of your volume attributes or if you want to use your volume attriubutes on another computer (or in another browser), you can use the Export and Import functions.

Volume attribute definitions are exported to a file TreeModel_Attributes.xml, which can then be imported on another computer. Please note that importing volume attributes will overwrite any volume attributes that are currently defined.

Aboveground, Belowground and Total Carbon is calculated based on species cohort allometric equations and a C fraction of 50% of dry matter. These single tree biomass C stock equations can be found in the Ireland’s National Inventory Report 2021 published by the Environmental Protection Agency. The most suitable equations are adopted for appropriate species (e.g. Spruce is adopted for Sitka spruce).

In this part of the application, you can choose whether to include assortments in the calculation result.

There is option to select the default assortments (which have been defined by the Department of Agriculture, Food and the Marine), to create a copy of the default assortments and edit it further, or to create your own definition of assortments.

Only one assortment definition can be used for the calculation. If none is selected, output without assortments (with only volume and carbon calculations) is created.

Each assortment definition must include a grouping of tree species. After the species groups are defined, individual assortments can be added for each species group.

Each assortment is defined by several attributes:

• Assortment name
• Min. diameter of top end (cm)
• Max. diameter of top end (cm)
• Max. diameter of butt end (cm)
• Min. log length (m)
• Max. log length (m)
• Step of log length (m) - if the same assortment allows only for specific lenghts (that are between min. and max. log lenght), step can be defined.
• Allowance (% or cm) - to account for cut loss caused by cutting the stem into assortments.
• Max. taper (cm/m)

The order of assortments is very important because the assortment calculation algorithm prioritizes assortments that are higher in the list. The order can be changed using the arrow buttons below the list of assortments.

Most of the assortment parameters are not required. If not filled in, default value is used, which is visible if the field is left blank.

Your defined assortment groups are saved on the server and bound to your browser. If you want to make a backup of your assortment definitions or if you want to use your assortment definitions on another computer (or in another browser), you can use the Export and Import functions.

Using this part of the application, you can calculate the volume and carbon stock of individual trees or within the forest stand.

For each tree, you must provide at least three tree attributes:

• Species
• DBH (diameter at breast height, typically measured at height of 1.3 m)
• Tree height

You can also provide additional tree attributes to make the volume calculation more accurate. These attributes are optional:

• Upper diameter - diameter of the tree stem at higher height (above the DBH measurement height), typically measured at 1/3 of the total tree height.
• Upper height - height at which the upper diameter was measured. If this field is left blank, it is assumed that it was measured exactly at 1/3 of the tree height.
• Stump diameter - diameter of the tree stump (measured below the DBH measurement height), typically stump diameter is measured at 1% of the total tree height.
• Stump height - height at which the stump diameter was measured. If this field is left blank, it is assumed that it was measured exactly at 1% of the tree height.

Single tree calculation allows you to quickly calculate the volume of a single tree, by simply filling the form and pressing the Calculate volume button. Single tree calculation also produces a diagram of the calculated stem profile.

Single trees (Batch) and Stand allows you to calculate volumes for large numbers of trees at once. Tree data must be stored in Microsoft Excel table (*.xlsx or *.xls file). Batch processing is done in several steps:

1. Step 1: Stand Description - Provide a name for your data along with the Total stand area of the forest and the sampled area where the data was recorded.
2. Step 2: Trees - Load your excel file using the Open file button. The file is then uploaded to a server and headers are extracted from the table. NOTE - the application expects the table to have a header and therefore treats the first row in the table as a header row. Data can be previewed to ensure successful import. Information for Species and DBH is matched here (including units). Species can be stored in the file as a text (species name) or numeric codes can be used instead to avoid mistakes and spelling errors. The species that can be used and corresponding codes are shown in the table (found at the top of the page).
3. Step 3: Sample trees - After the file is loaded, you must assign which columns contain which tree attributes and where the data is coming from (same sheet or another file for tree heights). All of the attributes except tree species are expected to be numeric and you must also specify which measurement units are used for each attribute.
4. Step 4: Species groups - After you have assigned columns to tree attributes, you can assign the Species to the Species Groups. For example a forest may contain Sitka spruce and Birch which must be assigned to the project within this section.
5. Once these steps are complete, you can click the Calculate volume button.

Ireland’s Tree Volume and Carbon Calculator has been developed to allow forest owners and managers to estimate tree volume and carbon using basic tree information for the main conifer and broadleaf tree species. Tree volume is an important unit of measurement as it details the size of a tree, which can be used to inform forest management decisions. While the calculator provides information of the volume and carbon stocks in a forest or tree using data provided by the user, the calculator is not appropriate or intended to be used as any part of a carbon trading platform.

Users who intend using the calculator for planning or investment purposes are urged to thoroughly review the information provided. It may be advisable in certain cases to engage professional advice.

While every effort has been made to ensure the information provided is accurate, the Department of Agriculture, Food and the Marine does not accept any responsibility or liability for errors of fact, omission, interpretation or opinion that may be present, nor for the consequences of any decisions based on this information.

Any errors on the page or further queries can be reported to Forest Sector Development: fsd@agriculture.gov.ie