The Man on the Land

Northland Age, Volume 2, Issue 46, 19 June 1906, Page 6

The Man on the Land

WEEDS AND TIIEIR SUPPRESSION. Any plant growing whore it is not wanted is a weed. It matters not if the plant in question is in general a useful one ; so long as it occupies ground which is intended for growing other crops it must he classed as a weed. According to this definition it will he seen that wheat, rape, and potatoes are weeds if growing amongst other crops where they were not sown intentionally. This should not be forgotten, although the term weed is usually associated with plants such as thistles, couch, charlock, or docks, which arc never intentionally cultivated. The most serious objections to weeds may be stated in a few words as follows: —They absorb from the soil moistures and manures which would otherwise go to nourish and increase the crop which is being cultivated. They “ crowd ” the crop, screening it from obtaining an adequate amount of light, which is necessary for healthy growth, and for the proper assimilation of the soil and air constituents. The effect of this screening is to hamper the growth of the plants during early life, especially in the case of crops of slow growth. Many weeds—e.g., bindwood and cleavers—pull down cereals, or assist in their downfall, rendering the work of cutting at harvest both difficult and expensive. Weeds may harbour, or favour the development of, insect pests, as charlock does the turnip “ fly,” or they may temporarily harbour rusts and mildews, which spread to the cultivated crops later. The pecuniary value of samples of cereals is reduced by the presence of garlick, cleavers, and vetches, and the market value of hay and other farm produce is similiarly lowered by certain weeds or their seeds. Some weeds taint the milk of cows which have fed upon them, whilst others e.g., meadow' saffron and water hemlock—are poisonous to stock. Most fanners recognise that it is impossible to obtain the best returns from the land when w’eeds are allowed to grow unchecked. Few, however, may be aware that in many cases the yield in crop on even a moderately weeded area may be from 40 to 50 per cent, higher than on a similar unweeded area. The most obvious mode of suppressing weeds is to prevent their seeding. When it is recognised that an ordinary charlock plant produces more than 1,000, and a moderate - sized poppy at least 10,000 to 15,000 seeds, the force of the adage that “ one year’s seeding is seven years’ weeding ” is obvious. Further, as many weeds produce seeds which do not germinate uniformly, the mischief is greater than at first sight appears, for they may lie dormant in the soil and come up

subsequently at inconvenient times. The prevention of seeding should extend to weeds growing in hedgerows and on roadsides, waste places, etc. Under no circumstances should imperfectly cleaned seed be either purchased or sown. At the same time care should be exercised as to the disposal of screenings, sweepings of haylofts, etc. Such refuse should be thoroughly scalded before j given to stock, or burnt. Deep ploughing is sometimes resorted to with considerable success, many seeds rotting when deeply buried. Others, however, remain dormant under such circumstances, without losing their vitality, and may subsequently be brought to the surface. Shallow cultivation and the preparation of a good tilth are more advisable, as by this means the seeds are encouraged to germinate, when they may be destroyed by further stirring of the soil. Such a method, taking care to keep the seeds near the surface, will clear the ground of many annual and biennial weeds, such as poppy, charlock, and some species of thistle. The eradication of perennials, such as couch, bindweed and (creeping thistle, needs careful and welldirected effort. These plants are propagated by underground runners bearing buds, and the best treatment where they are concerned is shallow ploughing and thorough cultivation, the weeds being collected and burnt, or the weeds may be brought to the surface and left to the drying effects of wind and sun. Iland pulling and total removal of weeds is the most efficient means of destruction. Digging with fork or spade, or collection by means of the harrow after being loosened with the plough may also be adopted, but these methods are all expensive, and only resorted to when other plans have failed or are inapplicable. In every case collected weeds should be burnt. Judicious cutting with spade, hoe or scythe will destroy all weeds, but ill-timed cutting may only encourage what it is desired to suppress. Many weeds when cut near the ground send up new stems, and these are produced at the expense of food stored below grouncFfin the previous season. The growth of these secondary stems weakens the plant as a whole, and if, when produced, they are immediately cut off, and the process repeated, total destruction will be the result no matter what the plant may be. The first cutting should be early in the year, and as often after that, throughout the summer, as new shoots appear. If left too long they

may either seed, or train store up food in the roots in preparation for the next season’s growth. One cutting in the case of perennials is quite valueless. Rushes, sedges and horsetails are indicative of a sour soil, and this can only be remedied by draining. The application of manure and artificial fertilisers induces considerable changes in the character of the herbage on pastures, and of the weeds on arable land. For example, nitrogenous manures stimulate the growth of useful grasses, which tend to choke out buttercups, cowslips, and other weeds or less useful plants. The sour condition of the surface soil can be partially remedied by a dressing of lime, which is more or less a specific against sorrel, corn marigold, and some other weeds. The application of sewt. to Bcwt. of basic slag per acre to pastures on stiff clay land often has a wonderful effect in encouraging clover, and generally improving the herbage. Close feeding with sheep will often check certain plants as ragwort, and prevent them seeding.—British Board of Agriculture.