PLATE 49. 



SWEET GRASS, Hierochloa borealis, R. & S. 



Other English names : Indian Hay, Vanilla Grass, Seneca Grass, Holy 

 Grass. 



Other Latin names : Holcus odoratus, L. ; Hierochloe borealis, Roeni. 

 and Schultes; Savastana odoratcf (L.) Scribn. 



Native. Perennial, deep-rooted, with wide-spreading white rootstocks 

 which produce in summer many barren shoots with long flat shining leaves 

 over a foot in length, of a deep green. Flowering stems thrown up very 

 early in spring, the, first flowers opening when the stems are only a few 

 inches out of the ground. Panicle pyramidal, 1 to 2 inches high, loose dur- 

 ing flowering, with spreading branches, contracting as the seeds ripen, when 

 the stems are 12 to 18 inches high ; the sheath with its short blade below the 

 middle. Spikelets drooping, with shining papery outer glumes which are 

 yellowish, tinged with purple, 1-seeded but 3-flowered, two male flowers 

 with 3 stamens between downy ciliate-margined scales, and one fertile 

 flower inside 2 smooth scales with 2 anthers and. a double plumose pistil. 

 When the seeds are ripe, the whole panicle becomes dark golden l:rown. 

 Seeds [Plate 54, fig. 39 natural size and enlarged 8 times] enclosed in 

 the inner scales, small, ^ of an inch, oblong. Whole plant sweetly aro- 

 matic, with the fragrant principle of the Tonka bean and Sweet Clover 

 (Coumarin). 



Time of Flowering : April to May. Fruit ripe by the beginning of 

 June. 



Propagation : By seeds and running rootstocks. 



Occurrence : Rare in the eastern provinces and growing in damp places 

 by streams and rivers. In the West, in all kinds of soil, extremely abundant 

 and very difficult to eradicate. 



Injury : This early ripening and deep-rooted grass is very persistent 

 in the rich lands of the West, where it smothers out all kinds of crops. 



Remedy: Mow and burn before summer-fallowing so as to avoid 

 ploughing down ripe seeds. Ploughing for summer-fallows must be deep. 

 Good results have been secured in Manitoba by ploughing in spring when the 

 Sweet Grass is in flower and then seeding down heavily at once. 



This grass is often incorrectly spoken of in the West as "Quack" or 

 "Couch Grass," quite a different grass, which flowers at the end of June, 

 roots near the surface of the soil, and can be killed by shallow ploughing 

 followed by frequent cultivation. Sweet Grass flowers in April, and shallow 

 ploughing merely stimulates its growth. 



92 



