Processes can be a variety of things ranging from prairie dogs to bluster rust and fire events to droughts. In general, there are two basic roles that processes can play.

First is in the pathways where the users can identify what change a process makes (if any) to the "next-state" for the vegetation community. The vegetative pathway in the image below controls how Douglas Fir changes in the B1 ecological grouping when the species is being influenced by succession.

The second role is to influence all the other system knowledge that has an interface screen where "columns" for processes can be selected from pull-down menus. There are some types of system knowledge where processes don't have an impact and these have different interface screens where "columns" is not a choice.

The intent is to let users identify the specifics of the process roles and impacts. For each zone there is a default system knowledge that came from many workshops made when the zone was first created. However these default choices are often changed for specific analysis by different sets of users and they load their own system knowledge files on top of the default logic. This overrides the default logic (in source there are boolean checks for whether the system knowledge used is default).

What role exactly processes play in any given simulation is in large part left to the user. This is entirely by design and is most often not the same as the default system knowledge. For example one set of users could say the the process of mountain pine beetle in the pathways kills all of one tree species. Another set of users, in the same zone, could decide the process doesn't kill all the species, just changes size class; so the "next-state" in the pathway is different. They do both use the pathways to identify the next-state, just in fundamentally different ways. Likewise some users will want to use mixed-severity-fire process in the probability logic screen for DF-Beetle to give a different probability if MSF occurs. Then there will be some users who do not use it in the DF-Beetle logic screen. The way in which users choose to use the process varies, but they all have the ability to choose to use the process to influence other processes probability of occurring.