OF SCOTLAND.

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tilth, and completely to eradicate all root weeds. Betweenthese successive operations, repeated crops of seedling weedsare brought into vegetation and destroyed. The larvae like-wise of various insects, together with an infinite variety of theseeds of weeds, are exposed to be devoured by birds, whichare then the farmer’s best friends, though often proscribed ashis bitterest enemies.

Some writers on husbandry have condemned the use of theharrow and roller in the fallow process, alledging, that frequentploughing is all that is necessary to destroy root weeds, by thebaking or drying of the clods in the sun and wind ; but ex-perience has ascertained, thatfrequent turningover the ground,though absolutely necessary while the fallow process is goingon, can never eradicate couch-grass or other root weeds. Inall clay soils, the ground turns up in lumps or clods, whichthe severest drought will not penetrate so sufficiently as to killthe included roots. When the land is again ploughed, theselumps arc simply turned over and no more, and the action ofthe plough serves in no degree to reduce them, or at leastvery imperceptibly. It may be added, that these lumps like-wise inclose innumerable seeds of weeds, which cannot vege-tate unless brought untler the influence of the sun and airnear the surface. The diligent use, therefore, of the harrowand roller, followed by careful hand picking, is indispensablynecessary to the perfection of the fallow process.

When effectually reduced to fine tilth, and thoroughlycleaned from root weeds, the fallow is again ploughed end-long into gathered ridges or lands, usually fifteen or eighteenfeet broad ; which are set out in the manner already describ-ed in treating of striking furrows or feiring. If the seed is tobe drilled, the lands or ridges are made of such widths as maysuit the construction of the particular drill-machine that is tobe employed. Any particular breadth that may be required,,s set off by means of marking poles of appropriate lengths,as already explained. After the land has been once gatheredby a deep furrow, proportioned to the depth of the cultivated