PLATE 41. 



RUSSIAN PIGWEED, Axyris amarantoidei, L. 



(Noxious: N.W.) 



Introduced. Annual. A tall coarse plant from 2 to 4 feet high, erect and 

 widely branching, very leafy. Stems grooved, rather pale at base, twigs and 

 lower side of upper leaves covered with rusty pubescence. Leaves lanceolate, 

 on short petioles, sparsely toothed. Flowers of two kinds ; spikes of anther- 

 bearing flowers, from half an inch to 3 inches long, terminate every branch- 

 let, and fertile flowers cluster the branchlets thickly below these, each one 

 producing a single seed. Seeds [Plate 56, fig. 74 natural size and enlarged 

 4 times] oval, flattened, T V of an inch, gray, with a silky lustre; sur- 

 face minutely lined and wrinkled lengthwise ; basal scar a short deep groove 

 across the lower end; many seeds have the close-fitting utricle or cartila- 

 ginous covering projecting above the top as a two-lobed wing ; this covering 

 is beautifully mottled with white zig-zag lines on a brown ground. Embryo 

 in a curved ring or loop around the outside of the central portion of the seed. 

 Russian Pigweed when young has somewhat the appearance of Lamb's-quar- 

 ters, but is a paler green, has a more wand-like habit of growth and, instead 

 of being mealy, is softly pubescent with short star-shaped hairs. When full- 

 grown, the whole plant forms a large pyramidal compound raceme; and, 

 when mature, the stems, bracts and papery calyx segments turn white and 

 make this weed very conspicuous. 



Tune of flowering: June; seed ripe July-August. 



Propagation: By seeds. Carried by the wind. The broken off plants 

 and branches become tumbling weeds, by which the range of this Pigweed 

 has been much extended. 



Occurrence : The species was first noticed in Canada in 1886 by the 

 i jadside at Headingley, 10 miles west of Winnipeg in Manitoba, to which 

 place it was said to have been brought direct from Russia. It is now found 

 along the lines of railway throughout the North-west, and has even been 

 detected on a railway bank as far east as Sherbrooke, P.Q. 



Injury : A leafy, gross feeding, wide-rooting annual which crowds grow- 

 ing crops and gives a very weedy appearance to farm lands. The thick woody 

 stems are very troublesome when crops are being harvested. The abundant 

 seeds, somewhat like small gray flax seeds, are found commonly in grain 

 from a few districts, infested by this rank-growing weed. It is, therefore, 

 most important that every care should be taken to prevent it from spreading 

 from roadsides and waste places, as it has every characteristic of a bad and 

 aggressive enemy. 



Remedy : Harrowing out young seedlings from a growing grain crop, in 

 the same way as Lamb's-quarters. Hand-pulling when not too abundant. 

 Mowing and burning plants by waysides, along railways and in waste 

 places. 



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