Abstract: An underlayment layer is configured to support an artificial turf assembly. The underlayment layer comprises a core with a top side and a bottom side. The top side has a plurality of spaced apart, upwardly oriented projections that define channels suitable for water flow along the top side of the core when the underlayment layer is positioned beneath an overlying artificial turf assembly.

Abstract: An impact absorption panel is adapted for playground use and comprises a panel section and a plurality of projections. The panel section is defined by a top surface and a bottom surface. The plurality of projections extend from the bottom surface of the panel section. The plurality of projections have a first stage and a second stage. The first stage is configured to collapse initially when subjected to an impact load. The second stage is configured to provide greater resistance to the impact load than the first stage. The panel section is configured to provide greater resistance to the impact load than the first and second stages. The first stage can also be distinguished from the second stage by virtue of having a comparatively smaller volume.

Abstract: An underlayment layer is configured to support an artificial turf assembly. The underlayment layer comprises a core with a top side and a bottom side. The top side has a plurality of spaced apart, upwardly oriented projections that define channels suitable for water flow along the top side of the core when the underlayment layer is positioned beneath an overlying artificial turf assembly.

Abstract: An underlayment layer is configured to support an artificial turf assembly. The underlayment layer comprises a core with a top side and a bottom side. The top side has a plurality of spaced apart, upwardly oriented projections that define channels suitable for water flow along the top side of the core when the underlayment layer is positioned beneath an overlying artificial turf assembly.