ROSE FAMILY ROSACEAE 
FIVE-FINGER. CINQUEFOIL 
Potentilla canadensis L. 
The Five-finger or Cinquefoil is common from New Bruns- 
wick to Georgia and west to Minnesota and Texas, and blooms 
from April to August. It spreads by slender runners 3-24 inches 
long. The leaves are palmately 
s-lobed and in their axils grow 
the 1-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 $-cleft and has a bractlet in 
each sinus, so that it appears 
1o-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 Strawberry, Potentilla mon- 
speliensis 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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