Why do my RNA traces show distinct peaks after RiboCop for Plants?

Depending on the source of plant material used for RNA extraction (e.g., leaf, root, etc.), microfluidics-based platforms (e.g., Bioanalyzer or TapeStation) can show traces with distinct peaks after rRNA depletion. These peaks correspond to highly abundant plant transcripts that are unrelated to rRNA. For example, leaves contain plenty of transcripts related to photosynthesis, such as the ones coding for the ribulose bisphosphate carboxylase/oxygenase (Rubisco).