When two leaves occur at one node, the arrangement is called opposite. Oppositely arranged leaves may be either 2-ranked, as in Mexican heather (Cuphea hyssopifolia) in the henna family (Lythraceae), or 4-ranked or decussate, in which each succeeding pair of leaves is at right angles to the pairs above and below them. Decussate arrangement of leaves is characteristic of the mint family (Lamiaceae), the maple family (Aceraceae), and some members of the milkweed family (Asclepiadaceae), such as Asclepias viridis.

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