PLATE 1 1. 



COW COCKLE, Vaccaria Vaccaria (L.) Britton. 



Other English names : Cowherb, China Cockle. 



Other Latin names: Sapotiaria Vaccaria, L. ; Vaccaria vulgaris, Host. 



(Noxious: N.W.) 



Annual. Introduced from Southern Europe. Stem simple, branching 

 above or much branched from the base, 1 to 2^ feet. Whole plant, smooth, 

 succulent and glaucous (gray-green like a cabbage). Leaves ovate-lanceo- 

 late, clasping the stem. Flowers pale rose-pink, i inch across, in loose 

 corymbose cymes. Calyx ovate, 5-ribbed and much inflated, and wing- 

 angled in fruit. The smooth roundish capsules contain about 20 round, 

 hard, dull black seeds [Plate 55, fig. 48 — natural size and enlarged 4 times] 

 about jV of an inch in diameter. These seeds are often confounded 

 with and spoken of as the seeds of wild vetches ; they can be told from these 

 of a similar size, by their minutely roughened surface, or by cutting them 

 open after soaking, when the entirely different embryo which lies in a circle 

 around the seed just beneath the seed-coat will be seen. It in no way re- 

 sembles the inside of a vetch or pea, which have two easily separable seed 

 leaves. 



Tinne of Flowering : July; seeds ripe in August. 



Propagation : By seeds only. 



Occurrence : As a troublesome weed, only in the Prairie Provinces. 



Injury: Abundant in grain fields in Manitoba, and the North-western 

 Provinces. This succulent plant absorbs much moisture, and its branching 

 head crowds out crops. Prof. Hitchcock quotes Prof. Aven Nelson, that in 

 1896 it was the worst weed of Wyoming grain fields, specially in spring 

 wheat; and Prof. Crandall reported that in 1893 it was so abundant in grain 

 fields of Colorado as to rank among the worst weeds. (Nevada Weeds III. 

 Nevada Agr. Exp. Station, Bui. 38.) 



Cow Cockle is particularly abundant and injurious in So>ithern Mani- 

 toba. The seeds are also suspected of having poisonous properties similar to 

 those of Purple Cockle. 



Remedy : As the seeds do not ripen very early, early summer fallow- 

 ing at short regular intervals will control this weed. The plants when in 

 bloom are very conspicuous and often large. Hand-pulling at that time has 

 been found very effective in the Mennonite settlements. The thorough clean- 

 ing of all seed grain is -cry advisable with this weed, as the indications are 

 that the seeds do not retain their vitality very long. Seeding down would 

 also crowd out any plants which came up the first year, and prevent them 

 from forming many seeds. Harrowing growing grain crops kills many of 

 the tender succulent seedlings. 



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