The hyphal system of the pileus trama is the number of types of hyphae: one type in a monomitic trama, two types in a dimitic trama and three types in a trimitic trama.

To establish the hyphal system, take a small piece of pileus trama tissue and mount in KOH to facilitate separation of the individual hyphae. Use needles to tease apart the hyphae before adding a cover slip and applying gentle pressure to spread apart the hyphae. Mature specimens should be examined, since young material can be monomitic, but later become dimitic as skeletal hyphae develop (as in Pleurotus djamor).

Generative hyphae are always present, and are septate and often with clamp connections. In a dimitic trama, skeletal hyphae (or rarely skeleto-ligative hyphae) are also present, along with generative hyphae. In a dimitic trama, the skeletal hyphae may be very common, and make finding generative hyphae difficult. In a trimitic trama there are generative, skeletal and binding hyphae.

Choose this state if: the hyphae of the context are of one type: generative hyphae. These are septate and often have clamp connections. Generative hyphae most often are thin-walled, and in agarics commonly inflate to as much as 40 micrometres in diameter, although in some genera they remain narrow, up to 10 micrometres in diameter. In some genera (such as Lentinula) generative hyphae are thick-walled at maturity, when they can be distinguished from skeletal hyphae by the presence of frequent septa, which usually have clamp connections.