840 EXPERIMENTAL FARMS 



5 GEORGE v.. A. 1915 



grown. Some, such as Orange Hawkweed, grow rapidly on cultivated land and are 

 equally at home on stony pastures. It is evident in a case such as this that the same 

 method of eradication cannot be prescribed alike for the two cases. 



(5) Its natural method of spreading, whether by seeds, surface runners, vmder- 

 ground stems, etc. 



(6) If spread by seeds or fruits, the manner of its dispersal should be known, 

 whether the fruits are carried by wind, as in the thistles, or by animals, as in the case 

 of blue bur, or have no special mechanism for dispersal. 



(7) Time of flowering and time of ripening of the seeds. In some cases the 

 latter will coincide with the ripening of the crop among which it is growing while in 

 others it may be earlier or later. 



(8) Time of germination of the seeds when self-sown in the ground. 



(9) Vitality of the seeds wheii buried in the soil. Opinions seem to differ as 

 to how long the seeds of weeds can remain alive in the soil, and further investiga- 

 tions will be necessary before the point can be accurately determined. Seeds, if kept 

 dry, appear to lose their vitality much quicker than buried seeds. There is no doubt 

 that many of the latter can g,erminate after being buried for twenty years. 



(10) Relation to moisture. The problem of destroying weeds is rendered more 

 difficult in a region with light rainfall, such as Alberta. Here the usual method 

 of ploughing the weeds inider after they have germinated is scarcely applicable at 

 certain seasons of the year, as the supply of moisture is not sufficient to induce the 

 seeds to genninate. Some weeds grow best where the soil is fairly damp; drainage 

 retards them and enables other plants to crowd them out. 



(11) Relation to temperature. As regards the exact temperature at which weeds 

 or weed seeds are killed by frost, we have little, if any, reliable information. 



(12) The susceptibility of weeds to "Chemical sprays. A number of experiments 

 Lave been made showing the action of various sprays such as copper sulphate, iron 

 sulphate, etc., on various plants, but the series of experiments ought to be extended, 

 and other chemical substances tried at various stages in the plant's history. It is 

 just possible that a spray which would have no effect on the foliage might injure the 

 flowers sufficiently to prevent the formation of seeds. 



A knowledge of the life-history of a weed in the widest sense as outlined under the 

 headings above would render th-e weed problem more easy of solution, especially if aided 

 by effective legislation. 



POISONOUS PLANTS. 



We are glad to note that the number of cases of poisoning due to plants reported to 

 us has not increased ; but we still receive numerous requests for literature on poisonous 

 and medical plants, with specimens for identification. The plants which we have had 

 most inquiries about, are given below. They are r-rranged in the following maimer in 

 the hope that although some of them are well kno-wn by their comnvon name and appear- 

 ance, the additional knowledge of their poisonous nature ma.y avert danger. 



POISONOUS. Rhus Toxicodendron (Poison ivy). 



Sium cicutaefoliiim (Water parsnip). 



Actaea ruira (Red baneberry). Solannm Dulcamara (Bittersweet, night- 



Actaca alba (White baneT)erry). shade). 



Anemone patens var. Wolfgangiana (Prai- " nigrum (Black nightshade). 



rie anemone). Taxus canadensis (American yew). 



Cicuta vagans (Water liemlock). Trillium erectum (Red trillium). 



Daphne Mesereum (Daphne). Trillium grandiflornm (Large-flowered tril- 



Equisetuni arvcnse (Horsetail). Hum). 



Iris versicolor (Blue flag). Trillium undulatum (Painted trillium). 



Lobelia inflata (Indian tobacco). Zygadcmis undulatum (Death camas). 

 Oxytropis Lamberti (Loco weed). 



Ottawa. 



