ROSE FAMILY 



ROSACEAE 



FIVE-FINGER. CINQUEFOIL 



Potentilla canadensis L. 



The Five-finger or Cinquefoil is common from Xew Bruns- 

 wick to Georgia and west to Minnesota and Texas, and blooms 

 from April to x'\ugust. It spreads by slender runners 3-24 inches 



long. The leaves are palmately 

 5-lobed and in their axils grow 

 the i-flowered peduncles, the 

 first of which usually occurs in 

 the axil of the second stem leaf. 



The flowers resemble those of 

 the Strawberry except that they 

 are yellow. The flat green calyx 

 is 5-cleft and has a bractlet in 

 each sinus, so that it appears 

 lo-cleft. The 5 roundish petals' 

 are yellow and notched at the 

 end. Stamens are numerous, and 

 the many pistils are collected 

 into a head on a hairy receptacle 

 that is dry instead of fleshy as in 

 the Strawberry. The fruits are 

 akenes. 



The Silver Weed, Potentilla Anserina L., is a com- 

 mon perennial of moist sandy flats and shores, abun- 

 dant in the northeast section of the state. Leaves and 

 the many-jointed runners are white hairy beneath. 

 The leaves are pinnately compound with 5-21 leaflets 

 alternating large and small. In the axil grows the largest yellow- 

 flowered Potentilla, with the usual structure for the genus. 



The Rough Cinquefoil or Yellow Strawberr}, Potentilla mon- 

 spelicnsis L., is another common species. It grows more erect 

 than the Five-finger and the leaflets are 3 instead of 5. This 

 species occurs over most of Canada to Alaska, south to Maryland, 

 Missouri and New Mexico. 



The largest of the genus in Illinois is the Tall Potentilla, 

 Potentilla arguta Pursh, also the only native white-flowered species. 

 The usually stout stem grows 4-40 inches high, is covered with 

 brownish hairs and is glandular above. The 7-11 leaflets are 

 pinnate instead' of palmate, ovate, toothed and downy beneath. 

 The Tall Potentilla inhabits rocky, gravelly or alluvial soil from 

 eastern Quebec to Maryland and westward. 



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