This paper discusses phylogenetic reticulation using linguistic data from the Automated Similarity Judgment Program or ASJP (Holman et al., 2008; Wichmann et al., 2010a). It contributes methodologically to the examination of two measures of reticulation in distance-based phylogenetic data, specifically the δ score of Holland et al. (2002) and the more recent Q-residuals of Gray et al. (2010). It is shown that the δ score is a more adequate measure of reticulation. Our empirical analyses examine possible correlations between δ and (a) the size (number of languages), (b) age, and (c) heterogeneity of language groups, (d) linguistic isolation of individual languages within their respective phylogenies, and (e) the status of speech forms as dialects or recently emerged languages. Among these, only (d) is significantly correlated with δ. Our interpretation is that δ is a realistic measure of reticulation and sensitive to effects of socio-historical events such as language extinction. Finally, we correlate average δ scores for different language families with the goodness of fit between ASJP and expert classifications, showing that the δ scores explain much of the variance.