mattermedia:

When we speak of social wholes with a high or low degree of hierarchization, we are basically dealing with a parametrization of the concept of assemblages. To parametrize a concept is to assign to it ‘control knobs that can have different settings at different times’ as DeLanda puts it. In his recent book Deleuze: History and Science (2010), the concept is parametrized in order to do away with another concept associated with it, namely, ‘strata.’ In so doing, DeLanda departs from the originators of the concept, Deleuze and Guattari, for whom assemblages are relatively heterogeneous entities in contrast to strata, which are composed of more or less homogeneous components. Instead of having two kinds of social entities, DeLanda proposes just one. Here is a passage from the book where he explains this conceptual innovation:

If we parametrized a single concept, then strata and assemblages would cease to be kinds and become phases, like the solid and fluid phases of matter. Unlike mutually exclusive binary categories, phases can be transformed into one another, and even coexist as mixtures, like a gel that is a mixture of the solid and liquid phases of different materials. 

What results is a streamlined social ontology, in which the tendency to misunderstand assemblages and strata as oppositional categories is circumvented. Stratification, or hierarchization, may now be conceived not as characteristics of entirely different kinds of social entities from assemblages, but rather, as phases of assemblages, degrees to which social wholes are affected by environmental factors over their lifetimes. What is entailed in DeLanda’s renewal of Deleuze and Guattari’s philosophical work is also the circumvention of a popular tendency to misinterpret trees and rhizomes, the arborescent and the rhizomorphic, as entirely different kinds of actual entities. In assemblage theory, trees and rhizomes are synonymous with hierarchies and meshworks (horizontality and verticality), and may be considered logics or tendencies of organization or collectivization. These logics are never found in a ‘pure’ form in an assemblage, but are always mixed, in varying proportions or ratios. [What Deleuze and Guattari describe as ‘states’ and ‘war machines’ must also be understood in this manner]. One of the chief benefits of DeLanda’s emphasis on phases that assemblages may pass through is that it highlights the fact that assemblages are continually changing, assemblaging. This move goes a long way towards bypassing habits of thinking that focus on actual objects, demanding instead that the genesis of actuality be continually accounted for.

Quotes from: DeLanda, M. (2010). Deleuze: History and Science. New York: Atropos Press.