10 Jii.v. 1917.] 1Im,/.v. 431 



Unfortunately for the farmer when pe-reunial weeds ap]>ear in 

 ruUivated lauds the difficulties often increase, as the only crops per- 

 mitting clearing operations being carried out throughout the growing 

 season are root crops, and, though cereals can be cut for hay on land 

 badly infested with St. John's Wort (/I i/jiericiim prfmatiini), this does 

 nothing towards suppressing the pest, as while the crop is growing the 

 weed is recovei"ing. 



Recently I saw a paddock tha( h;id liecu contiimously cropped for 

 seven years past' in infested St. John's Wort country. The land in 

 question had four ploughiiigs a year. Last year it was put out of 

 cultivation, with the result that St. John's Wort was a heavy crop c.n 

 this land, and possiblv lieavier than befoie cultivation took place. St. 

 John's Wort, bein,g of an extremely inflammable nature, should be 

 burnt wherever possible, as this alone would destroy enormous quantities 

 of seed, and it should be cut down to prevent its seeding at all. The 

 best time to cut this plant is when the flowering stems are well advanced; 

 this also a])plies to other weeds, as reser^'e forces are lower at this time, 

 they having been used to a large extent in forcing up flower sfenis. 

 A salt application at this time increases the shock and destroys the 

 plant. This plant thrives best in loose soils, no matter how pocr and 

 stony they may be, tlie deep root system enabling them to obtain the 

 necessarv moisture. It does not thrive so well in the heavy clay soils, 

 although in these the plant will seed freely, and seeds would be more 

 easily transported from these soils in the feet of stock than in soils of a 

 lighter nature. 



Apart from dredging, the seed is not water-borne to the extent that 

 is generally believed, for, although the seed must be shed into streams iu 

 immense quantities from plants overhanging the water, it would, soon 

 after falling, sink to the bottom. 



In my opinion, the chief medium of its spread is by means of stock 

 movements from infested areas, and also by fodder grown in badly 

 infested districts. Another factor in its spread on Crown lands is, I 

 believe, through the medium of rabbits. These, when dashing through 

 a crop of the weed, when the seed is ripe, cause lots of it to be showerec) 

 down upon them, and this either falls or is scratched out of their fur 

 probably on land previously free from the weed, as the seed is very small 

 and dustlike. The ease with which new centres of this weed can be 

 established can readily be understood when it is borne in mind that this 

 seed will germinate in 28 days. 



St. John's Wort has a wide range, being indigenous to England and 

 through Europe to China. It is the species that lias proved such a pest 

 iu Victoria since its introduction about 30 years ago. It is commonlv 

 known iu Bright as the Racecourse weed on account of its rapid spread 

 over that reserve many years ago. This plant is perennial, having 

 lierbaceous stems erect, and two-edged, of reddish colour, which stool out 

 freely from the base, forming a cluster of upright st«ms, sometimes 

 reaching to 5 feet in height, but more commonly about 3 feet, and 

 carrying at their tops bright clusters of yellow flowers, which later on 

 form three-valved seed capsules containing a great number of small 

 seeds. The branches and leaves are opposite. The latter are small, 

 having smooth ed,ges without stalks, and are in form elliptic-oblong 

 about half an inch long of a bluish green colour, and copiously supplied 

 with oil-glands showing as pellucid dots on the surface. It is from 



