Carmen Arsema Pérez Hernández
, Almudena Fernández Fontecha 

Research on the productive vocabulary of foreign language (FL) learners is scarce especially when it comes to researching children and immigrant heritage speakers (IHS). To address this gap, the present paper provides a comparative analysis of the lexical profiles and use of lexical organization and retrieval strategies of two groups of 6th grade monolinguals and IHS learners of EFL. Through a mixed-methods approach, we explore the number of types and tokens produced by each group in two semantic fluency tasks, the use of lexical clustering and switching strategies, and the nature of associations within clusters. Despite the advantage in lexical awareness attributed to bilingual learners, monolinguals outperformed them in most of the quantitative tests, although not significantly. Among others, we argue that the competition among the languages during the word retrieval process and, particularly, the distinctive characteristics of IHS could help explain the results.