SEEDS WEEDS. 



53 



height of 1 or 2 ft., produces seed abundantly, and grows persistently in grass cut by 

 a lawn mower. The tuVjerous sweet pea resembles the garden sweet pea, except in 

 the smaller size of its flowers. It has been under observation for 10 years or more, 

 and has continued to spread over the lield where it was first noticed. When first 

 discovered the land was in grass, but has since been cultivated with corn and pota- 

 toes, and is now reseeded, but the weed persists in the field, doubtless owing to its 

 root stocks and tubers which were not destroyed by cultivation. 



The bird vetch or wild pea, L. R. Jones and A. W. Edson ( Vermont Sta. Rpt. 

 1001, pp. l^ol-:?54).— The bird vetch or wild pea ( Vicia crucca) is frec^uently found in 

 the meadows of Vermont and in some places is spreading quite rapidly. Wide dif- 

 ferences in opinion regarding the plant have been expressed, some regarding it as a 

 desirable forage plant, w'hile others consider it a troublesome weed. A brief descrip- 

 tion is given of this vetch, and its value for pasture and hay are indicated. F(^r the 

 purpose of comparison the following table has been prepared in which the analysis 

 of the bird vetch hay is compared with that of red clover hay: 



Anah/sis of bird retch licuj. 



The plant is said to be very deceptive, as an apparently dense growth when cut for 

 hay gives a much smaller yield than timothy and much less than clovers. It tends 

 to make the hay dark colored and musty, and is difficult of handling on account of 

 its growth in tangled masses. It is said to l)e difficult to eradicate from most soils, 

 but on the experiment farm it was killed by short rotation and clean cultivation. On 

 the whole, the authors consider this vetch as a weed rather than a useful plant, and 

 recommend its eradication. 



The Canada thistle (Circium arvense), Samso-Lund and E. Rostrup (A'. Norske 

 VUlcmk. ScM:. Skr., 1901, pp. ir,2). 



Killing' weeds with chemicals, L. R. Jones and A. W. Edson ( Vermont Sta. Rpt. 

 1001, pp. 247-251). — In continuation of previous work in this line, the authors tested 

 carbolic acid, an arsenic-sal-soda mixture, arseniate of soda, and two trade prepara- 

 tions — Smith's Weed Killer and Henderson's Weed Destroyer. In 1900 further trials 

 were made, in which sulphuric acid was tested, as well as carbolic acid and sodium 

 arsenate. As a result of all the experiments, which are summarized, the authors 

 conclude that walks, drives, tennis courts, and similar places can l)e kept free from 

 weeds ])y the use of chemicals. The relative value of the chemical depends upon its 

 immediate action as a herljicide and the persistence of its effect. AVhen both of these 

 factors Avere considered the arsenical compounds were found to be far superior to any 

 other chemicals tried. Of the arsenical compounds tested, their efficiency in order 

 of enumeration is as follows: Henderson's Fluid Weed Destroyer, arseniate of soda, 

 Smith's Weed Killer, and arsenic-sal-soda mixture. The chief difference between 

 these was found to be in the persistence of the effect, but all of them endured for a 

 year or more. Considering the efficiency and cost, where small areas are to be 

 treated and expense not considered, the authors would recommend Henderson's 

 Weed Destroyer, since it is most convenient and most efficient. For larger areas, 

 where convenience and economy are considered, the arseniate of soda is preferred. 

 For killing weeds in lawns, where it is desired that useful plants shall occupy the 

 soil as soon as possible, crude carbolic acid is preferred, since it is prompt in its action 



