36 
COI.ORADO AgriculturaIv 
3. Golden Dock {Rumex persicarioides L.) (Fig. 44). — Seeds russet 
ill color, shiny, 1 mm. long, .8-1 mm. wide, 3-angled, sides equal, ridges snarp 
or acute ; achenes acutely pointed as in R. crispus. 
Fig. 44. Golden Dock (Rumex per- 
sicarioides). A. Calyx enclosing achene. 
B. Achene. x 10. 
2. Knotweed 
{Polygonum (Tourn.) L.) 
Achenes either lenticular, compressed or 3-angled ; sides usually unequal ; 
achenes longer and usually larger than in Rumex; embryo near the end of 
the achene in one of its angles ; achene usually exceeding the calyx in length 
when calyx is persistent. 
Key to Species 
Seeds 3-angled 
Seeds with equal sides 1 ../’. convolvulus 
Seeds with unequal sides 2..P. aviculare 
Seeds flat, napiform in shape 
Seeds nearly circular in outline, 3 mm. long, 3 mm. wide 2..P. pennsylcanicum 
Seeds oval in outline, 1.5-2 mm. long, 1-1.5 mm. wide.... A..P. persicaria 
Fig. 45. W5 1,.d 
Buckwheat 
(Polygonum con- 
volvulus). X 10. 
1. Wild Buckwheat {Polygon urn con- 
colulus L.) (Fig. 45). — Seeds dull black, 
the three sides equal and slightly concave, 
2. 5-3.5 mm. long, 2-2.5 mm. wide, 2-2.5 mm. 
thick: part of the calyx is often persistent: 
ridges rounded or obtusix 
