A non-native weedy species that occurs in recently disturbed sites, along with various annual grasses, Amaranthus, etc. The slopes around the pond certainly qualify as disturbed, and even though many native species were planted, there is a vast growth of non-native, mostly annual, species. They will vanish quickly and by next spring others will take their place, and eventually many of the native species planted earlier, will take over. Or at least we hope so.