top of page

Yearly Inventory

Updated: Nov 8, 2022

Yearly inventory I'm defining here is where a separate inventory is made and maintained over the span of a single year. At the end of the year, a copy is made for the new year and maintenance continues anew.

This has advantages like an archive of prior years and freedom to change stands as needed during the current year without fear of messing up prior year archives.

There are a few necessary features to accomplish this though and they can get a bit obscure. And like any process, there are the nice to haves that are usually works in progress.

I'm hoping to discuss and explain how Assisi accomplished these here.

The Assisi Library is "open blog space" where you are encouraged to comment and even edit the blog itself. Posts are not fixed in time so the blog itself will get updated as we go.

Cruise Data and Inventory Units

It is typical for cruise data to be stored in a single unit separated from units made for each inventory year. The cruise data unit is not an inventory: it is simply a repository of all cruises for all time. The inventory units typically take on the year as their name.

The cruise data unit is filled with stands (or strata) and actual cruise data to be compiled. The inventory units are filled with stands that exist during the year and have expansions rather than cruises in them.


To give the inventory units an actual inventory (trees, volumes etc.) the cruise data are compiled and then results copied over to inventory stands. This process is called Expansion in Assisi.

Each stand in an inventory unit gets an expansion record that determines the cruise data source inventory will be copied from. Cruise data source stands can be mapped to any number of inventory stands. The source cruise data stand and the destination inventory stand end up having the same content: trees, species, cover, etc.

Growth Estimation

Cruise data can be many years old. Assisi's growth process estimates growth and carries out thinnings and other actions so that the older cruise data becomes a better estimate of today.

Where to Store History

History of actions can be stored on either the cruised stands and/or the inventory stands. The choice depends on what stands you are growing to obtain your current year inventory.

When history is on cruise data, cruise data should be grown first then expansion run. If a cruised stand was thinned or modified, you want that history carried out during growth before you copy the results over to inventory stands. Storing history on cruise data also has the advantage that it occupies a single location for all inventories.

When history is on inventory stands, expansion from a cruise should be performed first then growth run. This has the advantage of being able to record partial stand harvests that create new polygons. Remember than cruise data reflects a stand as it existed at the time of cruise. Inventory stands need the cruise results at that time, but may have been split into new stands since. That split occurs on the inventory stands and in a certain year so recording that history on the inventory stand makes sense. But the disadvantage is that inventory stand history must exist in every yearly inventory. Space is generally not a problem so this may be a minor disadvantage.

Processing Expansions

The process of Expansion in Assisi starts with adding Expansion records to stands. Expansion records are kind of like Cruise records in that both specify what the source of an inventory is. For a Cruise, the source is a cruise. For an Expansion, the source is another stand's inventory.

Define Expansions as you would Cruises using the Field Data Editor.

Note that each Expansion defines the source unit and stand as well as overrides for the stand's growth year, total and breast height age. After the expansion is processed,the destination stand will have the same inventory but different growth year and age if the overrides are set.

Processing Expansions

Expansions are processed like growth is processed: select stands (shift click) and press the Expand button:

Expansion does not compile cruise data so selected plots are ignored. Each source stand should already have an inventory. Whether cruised or grown, whatever the source stand's inventory is, it will be copied to the destination stand.

27 views4 comments

Recent Posts

See All

How Assisi Forest records, compiles and grows timber volume defect.

bottom of page