PLATE 36. 



BLUE BUR, Echinospermum Lappula, Lehm. 



Other Englisli names : Stickweed, Sheep Bur. 



Other Latiu names : Myosotis Lappula, L. ; Lappula Lappula (L.) Karst. 



(Noxious: N. W.) 



Introduced. Annual and winter annuul. Erect, branching only above 

 or from the base. Whole plant covered with short white hairs, which give 

 it a grayish appearance. Leaves linear-oblong; root leaves about 3 inches, 

 narrowed at base ; stem leaves, sessile. Flowers small, pale blue, about ^ 

 inch across, erect, in leafy-bracted, more or less one-sided racemes. Seeds 

 (nutlets) [Plate 56, fig. 71 — natural size and enlarged 4 times] about \ 

 inch, dark brown, pear-shaped, surface very rough; inner face sharply 

 angled, outer face rounded, bare of spines in the centre but having on the 

 sides a double series of long stiff spines, each of which has at its apex a 

 star of from 3 to 4 sharp hooks. 



TiTne of Flowering : From June ; seeds ripe July. 



Propagation : By seed only. 



Occurrence : By roadsides and in waste places in the East. In the 

 West chiefly in corrals and around buildings, but recently spreading with 

 alarming rapidity into cultivated land, where it is sometimes abundant on 

 fields left for summer-fallowing. 



Injury : Seed very troublesome as a bur in wool ; also frequently found 

 as an impurity in commercial seeds, when many or all of the long barbed 

 bristles may be rubbed off, but there is no trouble in recognizing it from 

 the angled inner face with the small basal scar at the bottom of the cen- 

 tral ridge, and the unarmed area on the outer face. 



Remedy: Early summer-fallowing; fall or spring ploughing. Sow 

 clean seed. 



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