WEEDS

Waipa Post, Volume 36, Issue 2147, 21 April 1928, Page 3

WEEDS

THEIR ERADICATION WORTH MILLIONS. Every New Zealand farmer should look on weeds as being chief among his worst enemies, and it is to be feared that too many- look on them with more or less indifference (writes Mr Primrose McConnell in the April issue of the New Zealand Farmer). Throughout all ages, and in all countries, the cultivators of the soil have had to wage constant war*pth weeds, and had they not done so the cultivation of food crops would have become an impossibility. In a report of Reading College Farm it is stated that the difference in yield

between "no weeding" and keeping clean by hand, after the mangel crop was singled, was as that between 100 and 240, the actual yields being 161 tons and 39 tons respectively. A weedy plot of potatoes yielded 4 tons 10 cwt per care, while a clean plot yielded 8 tons 15 cwt. Two plots of oats infested with' charlock yielded 45 and 24 bushels respectively, while plots kept free of weeds gave 67 and 76 bushels respectively. And what of the weeds that infest our pastures? The loss arising annually from their presence must be enormous—almost beyond calculation —and, unfortunately, we have no effective remedy. Certain weeds may be smothered out by stimulating the growth of the grasses and clovers with suitable topdressings, but a great many remain in .spite of our best efforts. Climate and the pioneering system of farming have developed the weed evil to such an extent that it may be safely stated that half of the land in New Zealand is occupied by weeds, or plants that might be replaced by others of more value from a farmers' standpoint. Land absolutely free from weeds is an impossibility, mat if the weeds in New Zealand could be reduced by one half the monetary advantage would run into millions of pounds, and by the aid of a little more care in cultivating operations no practical farmer will deny that this curse ecan be mitigated very greatly. Good arable land may be seen that is growing nothing but weeds. In many instances the evil is caused by farmers trying to cultivate large farms with an expenditure of labour that might be more profitably applied to half the area. Take the thistle, for instance, which is not by any means one of the worst of our weeds. Not to mention the moisture that it removes, it takes from the soil 17 per cent as much nitrogen as there is in clover, and it covers a very great deal of land that might be occupied by profitable plants. It should be convincingly obvious to all farmers that weeds must have food like all other plants, consequently they deprive a crop, or a pasture, of a large amount of available nourishment; and when not checked weeds almost invariably grow more vigorously than the desired plants. Certain weeds will take more potash and lime out of the soil than two good crops of grain from the same area. On arable farms there is often too much unploughed land adjoining the fences and hedgerows, on which numberless weeds flourish and seed. Such places are ideal breeding grounds, for insects that are injurious to cultivated plants; so much so that in certain parts of Europe the weeding of hedgerows is compulsory, and, in many cases, fences of any kind have been done away with entirely. Many plant diseases have been traced back to weeds as a source of infection, and some weeds are directly injurious to farm live stock. Weed seeds are distributed by numerous agents, some of which it is almost impossible to control; but this only shows more clearly the great necessity of taking extreme care when dealing with weeds and their seeds. In the meantime we must do our best to kill the weeds with the means at our disposal; and, in order to save money and labour in the work of destruction, the weeds must be dealt with in the initial stage of their life. On arable land many weeds may be completely buried with the plough, but the seeds will lie dormant for many years, and germinate when the land is ploughed again. Nevertheless, it is a great matter to destroy existing weeds; and, if the seedlings are taken in time, their destruction will not be costly. It is often of great advantage to delay sowing farm crops, so that the land may be repeatedly harrowed, and the weeds killed as soon as the seeds germinate. The intensive farmer, who is growing two crops on the same soil each year, provided he takes care to sow clean seed, can keep his land cleaner, and at less cost, than he who is growing only one crop, because the land is often stirred, and weed seeds brought within germinating distance of the surface. Young, ambitious farmers are often laughed at by their elders when they attempt to seriously tackle this weed problem, and these elders point out that they could always make their farms pay with little or no outlay in weed eradication. Quite so; but our elders forget that they got possession of the land when it was in a weedfree state, and contained all its natural fertility, which they have whipped

up to its last gasp, and it Has served them their life-time. But in what kind of state, in the average case, has the land been left? A legacy of more or less exhausted and weed-infested land has been handed over, and all but the most bigoted will admit that those evils cannot be remedied by farming on the old lines. It is certainly a mighty problem, and in many instances will be an exceedingly costly one; but it must be tackled sooner or later, or a portion of the land will go out of cultivation entirely.