done, particularly if the roots are first loosened with a spud or some other 

 implement. The plants should be carefully piled up to dry and then burnt 

 or otherwise destroyed. The poisonous principle called cicutoxin is of a 

 resinous or oily nature and will contaminate water, if, as is sometimes done, 

 the pulled up plants are thrown into sloughs where they may be trampled 

 upon by stock. It is most advisable that stockmen should know the appear- 

 ance of these plants so as to destroy them whenever seen or, at any rate, so 

 as to keep their animals away from localities where they grow too abundantly 

 to be pulled out by hand. 



THE SUNFLOWER FAMILY, COMPOSITE. 



This, the largest family of flowering plants, includes many thousands of 

 species and is represented in all parts of the world. The characters of the 

 family are well marked. The flowers of all are composite, that is composed 

 of many florets or small flowers standing together on an expanded enlarge- 

 ment at the ends of the stalks and known as the receptacle. Individually, 

 these flower-heads or collections of many florets have the appearance of simple 

 flowers and are popularly so spoken of, as for instance, the flower of the Sun- 

 flower, a Daisy, or a Dandelion, while in reality each one is a large number 

 of flowers joined together at the end of a common footstalk, and what appears 

 to be a calyx is a cluster of bracts or small leaves. A striking character of 

 this family is that the anthers are united at their edges into a vertical tube 

 with the style inside it. The calyx of the florets, when present, is united with 

 the one-celled ovary, and in fruit is modified into a ring of silky bristles, 

 awns, teeth or scales, which is called the pappus. The true seed is enclosed 

 in a hard dry shell, like a small nut, botanically called an achene. The flor- 

 ets of composite flowers are of two kinds, both of which may sometimes be 

 seen in the same flower-head, as in the Common Sunflower. The marginal 

 or ray-flowers are strap-shaped and the smaller disk-flowers are tubular. 

 When the flower-head has ray-flowers, either throughout or round the edge, it 

 is termed radiate; when there are no ray-flowers it is said to be discoid. 



Our Canadian members of this large family are divided by Dr. Asa 

 Gray in his Manual, which is still used as the text book in most of our 

 schools, into two series according to the nature of the corolla. In the first 

 series, the Tube-flowered Composites, the corolla is tubular in all the per- 

 fect flowers, and regularly 5-lobed, strap-shaped only in the marginal or 

 ray-flowers which, when present (as is not always the case), have either only 

 pistils or have neither pistils nor stamens. In the second series or Strap- 

 flowered Composites, the corollas on all the florets of the head are strap- 

 shaped and perfect, that is, contain both pistils and stamens. To this series, 

 known as the Chicory family (Cichoriacece), the Chicory belongs and many 

 other plants with similar flowers, including many well known weeds, such 

 as the Dandelions, Hawkweeds, Sowthistles and Lettuces. By far the larger 

 number of our weeds belong to the first series, the Tube-flowered Composites ; 

 and in such large numbers of plants as are grouped under that one series, it 

 becomes necessary to subdivide them into tribes. 



In the ASTER TRIBE there are a few weeds of the Gumweeds and Flea- 

 banes which are worthy of mention ; but it is seldom that any of our Cana- 

 dian species of the true Asters become aggressive weeds. The GUMWEED 

 Grindelia squarrosa, Dunal, is a bright golden -yellow flowered plant of the 

 western plains. This seldom becomes troublesome in crops, although the 

 seeds [Plate 55, fig. 53 natural size and enlarged 4 times] have been found 

 among wheat screenings and have occasionally been sent in under the im- 

 pression that they were the seeds of Canada Thistle. They are, however, 

 larger, and are much flattened and more angular, grooved lengthwise, and 

 dullor in colour. The Gumweed is accredited with causing hay-fever in the 



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