[1] "Eradication of Lallang," W. P. Handover, _The Planter_, Vol. I., No. 1, August, 1920. It consists in the employment of _Mimosa gigantea_, which eventually smothers the growth of lallang. The seeds are sown broadcast, in drills, or in pockets, amongst the lallang. In the course of about three months it overtops the grass and proceeds to travel. At this stage the whole mass is pressed down, and the pressing is repeated at regular intervals. Under favourable conditions, in about twelve months, an impenetrable mat has been formed, which gradually forms a good mulch. When it is desired to remove the Mimosa, the mass (pressed down) is cut and rolled up like a carpet. Cleared in this manner, the area then needs regular weeding, in order to check the development of any stray lallang shoots. In actual practice it was found that the cost of this method was approximately two-thirds that of the usual digging method. GREEN COVER PLANTS.--Some years ago it was quite common to find green cover-plants employed on estates with the primary idea of minimising weeding costs. With most of these it was found later that their value was not real, and that they harboured diseases, and pests. Moreover, when they were removed, it was often found that an abundant crop of lallang and weeds resulted. There can be no question that certain plants can be employed with advantage, not only in the control of weeds, but also by reason of benefit to the soil in which they are established. These plants are leguminous, and their use is restricted almost entirely to young areas, inasmuch as they will not continue to grow when shade becomes marked. Of those best known in modern practice might be mentioned _Tephrosia candida_ (Boga bean), _Centrosema Plumerii_, and _Dolichos Hoseii_ (Sarawak bean). [Illustration: TYPICAL YOUNG CLEARING, WITH TIMBER. Young rubber plants in foreground. Two of these are easily distinguishable, both with small crowns of leaves.] It is wrong to imagine, however, that the establishment of such leguminous cover-plants obviates weeding. So far is this from being the case, that in practice it is found that the weeding "rounds" must be conducted at first with the same regularity as in ordinary working, but that naturally there is much less work to be done. As the plants develop, they can be pruned or dug into the soil, as the case may be. The addition of the green material to the soil, either by digging or by burying in open trenches, is calculated to cause improvement in the condition of the soil. There may thus be a close connection between weeding, soil conservation, and soil improvement. CHAPTER III _THINNING OF AREAS_ On this subject there is unanimity regarding the necessity for the operation. Divergence of opinion exists only as to a matter of degree.