This collection contains subsamples of aquatic macroalgae collected during point counts (NEON sample class: apc_perTaxon_in.sampleIDmacroalgae). Aquatic macroalgae point count samples are collected at 10 permanent transects in wadeable streams three times per year. Aquatic macroalgae samples are preserved in 2% glutaraldehyde. Samples are archived in 20 mL glass scintillation vials and stored in a temperature (17-18°C) and humidity controlled environment. See AOS Protocol and Procedure: Aquatic Plant, Bryophyte, Lichen and Macroalgae Sampling and the NEON Aquatic Sampling Strategy (https://data.neonscience.org/documents) for more information about this sample class. NEON datasets (https://data.neonscience.org/home) associated with this sample class include Aquatic Plant, Bryophyte, Lichen, and Macroalgae Point Counts in Wadeable Streams.