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Descriptive Flora 



Sonchus asper (L.) All Sow Thistle. 



Coarse, simple, hollow-stemmed, yellow-flowered plants with 

 milky sap, and crisp leaves, 1 to 3 inches long, prickly on the 

 shallow-lobed margins and midrib and clasping the stem with 

 ear-like projections that form a rounded flap on each side of the 

 stem. Flowers composite, yellow, similar to a dandelion, up to 

 1 inch across and consisting of all strap-shaped, pale yellow 

 corollas. Bracts and stalk below the flower covered with few 

 short, thick hairs, tipped by tiny, black-knobbed glands. Seeds 

 flat, 3-ribbed on each side and with a tuft of hairs attached at 

 the summit. March to June. A common roadside and waste 

 place weed. Introduced from Europe. 



Sonchus oleraceus L. Sow Thistle. 



Similar to Sonchus asper above but the upper stem leaves 

 have pointed projections at the base on each side of the stem 

 instead of the rounded ones which fold flat against the stems. 

 Leaves are not as rough veiny, and lower leaves are more deeply 

 cut always bearing a triangular terminal segment. Not as com- 

 mon as Sonchus asper. Introduced from Europe. 



Taraxacum officinale Weber. Common Dandelion. Blow-ball. 

 (Taraxacum taraxacum [L.] Karst.) 



A common lawn weed with a thick brown bitter root, a 

 cluster of root leaves, and bright yellow composite flowers 1 inch 

 or more across, singly terminating hollow flower stalks, 2 to 18 

 inches long. Leaves simple, 1 to 5 inches long, oblanceolate to 

 oblong, irregularly toothed or cut into toothed lobes. Flowers 

 composite, all the 100 to 200 corollas being strap-shaped and 

 golden yellow, singly terminating hollow stalks varying in length 

 according to the height of the surrounding grass or weeds. 

 Flowers are succeeded by a silvery seed puff, 1 to 2 inches in 

 diameter. Individual seeds each tipped by a tuft of white hair 

 like bristles. This is a native of Greece but is introduced here 

 and is now a common weed of all civilized parts of the world. 



