In the mid 1980s, isolated occurrences of Rigid Hornwort had established in the lake, and, by the mid 1990s, abundant quantities of other aquatic plants such as Ivy Duckweed and the liverwort Riccia Fluitans, were reported along open edges of the lake.
This situation is reached in the female flowers of duckweeds (Lemna), which comprise a single carpel, and in the male flowers of spurges (Euphorbia) which comprise a single stamen.