Modifiers matching weed:

• common,
• perennial,
• aquatic,
• annual,
• invasive,
• emergent,
• rare,
• regular,
• broadleaf,
• arable,

Simple categories matching emergent:

• property,
• plant,
• medication,
• values,
• therapy,
• use,
• space,
• problem,
• condition,
• behavior,
• capability,
• tree,
• subculture,
• virus,
• entity,
• flora,
• system,
• technology,
• group,
• quality,
• species,
• trait,
• state,
• phenomenon,
• disease,
• weed,
• infection,
• situation,
• process,
• case,
• economy,