RUSHES are well-known plants which appear in all soils, especially those which are fertile, when the water which cannot be evaporated remains in a stagnant state under the surface. They are most common on moist meadows with a retentive subsoil ; and as they not only occupy a space which might produce good herbage, but also greatly deteriorate the hay with which they are mixed, every means to destroy them are employed by industrious farmers. Formerly in this, as in most other instances of defect in the soil, only a temporary remedy was generally thought of. The rushes were mown down at particular times of the year, alkaline ashes and salt were spread over them, and in some cases they were destroyed by pouring boiling water ou the roots. But all these only killed the individual rushes, without removing the imnio diate cause of them, or correcting ;he stagnation of water which invariably reproduced them. The only effectual cure for rushy grounds is a complete system of draining. The truth of this assertion is so generally admitted, that it is unnecessary to dwell upon it. Wherever the Land can be effectually under-drained, rushes will generally dis appear as by magic. If they are strongly established iu the soil, it may take some time before they completely die away, even after drainage, at least in pastures which are not broken up; but if the land is ploughed and has a proper tillage, they will not survive the first year. In rich old meadows, which it would not be prudent to plough up. they may be destroyed by mowing them when they are in bloom, and immediately spreading ashes or salt over the place where they grew. This repeated twice will clear the ground entirely, and the draining will prevent their reappearing.
In heavy grounds which have been laid up in high ridges without thoroughly draining the land, and sown with grass-seeds to remain in pasture two or three years, it is not uncommon to see every interval between the atetches filled with rushes, especially if the land be reduced in fertility by overcropping. This indicates a wet subsoil, and suggests under-draining ; but the rushes are often caused by the very roundness of the' ridges, which is supposed to keep the land dry, but which accumulates the water in the furrows. If the land had been laid quite flat, it might have been too wet to produce good crops of wheat, but rushes would not have appeared. In very flat meadows rushes are only found where the land lies very low, with an impervious subsoil, or a want of inclination in the surface to carry off the super fluous water. What might at first sight be considered as an*anomaly, is yet perfectly true—no rushes are found in the best water-meadowa, although they are for a considerable portion of the year entirely soaked in water ; but the water is never allowed to stagnate for a moment, and is always kept running on and off.
The great advantage which has been obtained by the system of thoroughly draining compact soils, or those which rest on impervious subsoils, has induced proprietors and farmers of land to employ their capital in this most certain of all improvements, and the consequence will be, that in a few years rushes will only be seen in those low and unprofitable spots from which the water cannot be drawn off by drains, and where they will supply some small resource to the maker of mats and the repairer of rush-bottomed chairs.