This release of the MPP library includes the standalone Multi-Layer Canopy Model (MLCMv1) for the E3SM Land Model (ELM) that can resolve the micro-climate created by the vertical structure of vegetation. MLCMv1 includes support for heterogeneous computation architectures via the Portable Extensible Toolkit for Scientific Programming (PETSc) library, which provides scalable numerical solvers for CPUs and GPUs. The ELM-MLCMv1 includes four sub-models that represent: shortwave and longwave radiation, stomatal conductance, roughness sublayer, and transport of heat and water vapor through the canopy air space. ELM-MLCMv1 includes multiple stomatal conductance models (SCMs) that are based on semi-empirical relationships or optimization theory and may additionally account for plant hydrodynamics.