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Golden canna (Canna flaccida, Cannaceae)
Native; wet areas; southern states
Native; wet areas; southern states
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Capeweed (Phyla nodiflora, Verbenaceae)
Native
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Whitemouth dayflower (Commelina erecta, Commelinaceae)
Native
Native
According to Wikipedia, Linnaeus picked the genus name Commelina in honor of two renowned Dutch botanists of the Commelijn family (Jan and his nephew Caspar), using the two showy petals of Commelina communis to symbolize them. Somewhere else I read that the joke was the third small, mostly obscured petal symbolized a third, less well-known botanist of the Commelijn family.
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Virginia pepperweed (Lepidium virginicum, Brassicaceae)
Native
Native
In my north Florida hometown, boys occasionally would chew the seed pods of this plant for the novelty of the biting taste, similar to mild horseradish. Pepperweed is a member of the mustard family, which also contains radishes.
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Spotted sandmat (Chamaesyce maculata, Euphorbiaceae)
Native
One interesting thing about this common roadside weed is that within each cluster of tiny, white flowers, there is nearly always one that is pink. (I read somewhere that what looks like petals are actually specialized glands.)
Native
One interesting thing about this common roadside weed is that within each cluster of tiny, white flowers, there is nearly always one that is pink. (I read somewhere that what looks like petals are actually specialized glands.)
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Common wireweed (Sida ulmifolia, Malvaceae)
Native; member of the hibiscus family.
Native; member of the hibiscus family.
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Florida tasselflower (Emilia fosbergii, Asteraceae)
Non-native
Non-native
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Fire-on-the-Mountain, painted leaf (Poinsettia cyathophora, Euphorbiaceae)
Native
Native
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Tall jointweed (Polygonella gracilis, Polygonaceae)
Native _____________________________________

Nuttall's thistle (Cirsium nuttallii, Asteraceae)
Native
Native
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Creeping oxeye (Sphagneticola trilobata, Asteraceae)
Non-native
Non-native
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Pink purslane (Portulaca pilosa, Portulacaceae)
Native
Native
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Largeflower rosegentian (Sabatia grandiflora, Gentianaceae)
Native
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Hairypod cowpea (Vigna luteola, Fabaceae)
Native
Native
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Madagascar periwinkle (Catharanthus roseus, Apocyaceae)
Non-native
Non-native
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Southern beeblossom (Gaura angustifolia, Onagraceae)
Native
Native
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Walter's groundcherry (Physalis walteri, Solanaceae)
Native
Native
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Showy milkwort (Polygala violacea, Polygalaceae)
Native
Native
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Common ragweed (Ambrosia artemisiifolia, Asterceae)
Native
Native
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Shrubby false buttonweed (Spermacoce verticillata, Rubiaceae)
Not native
On March 25, 2011, "Anonymous," in a comment to this post, correctly identified this plant as Spermacoce verticillata, a non-native weed. I had previously labeled it as Alternanthera flavescens. Thanks, Anonymous, for the correction!
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Wild bushbean, phasey bean (Macroptilium lathyroides, Fabaceae)
Non-native
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Largeflower Mexican clover (Richardia grandiflora, Rubiaceae)
Non-native
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Rosy camphorweed (Pluchea baccharis, Asteraceae)
Native
Native
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Pitted stripeseed, piriqueta (Piriqueta cistoides, Turneraceae)
Native
Native
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Puncturevine (Tribulus terrestris, Zygophyllaceae)
Non-native
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