1 66 WEEDS OF THE FARM AND GARDEN 



shining, sometimes triangular. Originally from Europe 

 but becoming very common in waste places. 



Water Pepper (P. Hydropiper) is much like P. Persi- 

 caria, but more slender and often decumbent. It has 

 greenish flowers and slender, nodding spikes ; achenes dull 

 in color and the whole plant more or less acrid. Another 

 water pepper or smartweed (P. hydropiperoides) is a 



perennial, not acrid ; with leaves 

 narrowly lanceolate or oblong 

 and small flesh-colored flowers 

 in erect slender spikes ; smooth 

 achenes sharply triangular. 



Common Bindweed or Wild 

 Buckwheat (Polygonum Con- 

 volvulus, L.). A smooth or 

 scurfy annual with a trailing 

 or twining stem, two to four 

 feet long with naked sheaths ; 

 leaves hastate or pointed; 

 flowers in axillary clusters or 

 in interrupted racemes ; green- 

 ish with slender pedicels; 

 calyx five, rarely six-parted; 

 stamens eight; style nearly 

 entire, stigmas three; achene 

 Fig. 99. Smartweed. .Lady's three-angled, dull blackish, 

 thumb (Polygonum Persicarta). 1 j /- 



obovoid. Common in waste 



places and especially in grain fields of the North through- 

 out North America. Native also to Asia and Europe, 

 probably introduced early with grains. Very commonly 

 found with wheat and oats seed in the North. 



Pennsylvania Smartweed (Polygonum pennsylvanicum, 

 L.). This smartweed, sometimes called heart's ease, is 

 common in low grounds and corn fields. Peduncles of 

 flowers with glands. 



Slender Smartweed (Polygonum lapathifolium, L;). 



