They sow’d it so thick, that the Plants must needs be very small; and when Ten of them were no bigger than one good single ho’d Plant would have been, in the same Space of the Earth’s Surface, they could have but a Ninth Part of the Earth’s Depth, which the one would have had. The Defect of Depth must be therefore made up, in some Measure, by the extraordinary Richness of the Surface. Upon this Account few Lands were capable of bearing Medica. Their sowing it so late made the first Waterings necessary; and the Shortness of the Roots required the repeated Rigations, after the Crops were cut: For Columella saith in Lib. ii. Cap. 11. Cum secueris autem, sæpius eam rigato. But had it been cultivated by the hoeing Method, the Tap-roots would have descended as deep as a Well, and, from the Springs below, have sent up Water to the Plants, besides what the Hoe would have caused the horizontal Roots to receive from Dews at the Surface above. At how much a cheaper Rate Water is supply’d by these Means, than by carrying it perhaps a great Way, and then sprinkling it by Hand over the Beds, which were made Ten feet wide between Path and Path for that Purpose, let any one judge; as also what a laborious Task it was to pick out the Grass with Fingers from amongst it, in the hard dry Ground in the Summer, after mowing the Crop, as Columella directs in his foremention’d Chapter, which the Horse-hoe would have done with Ease, at a Twentieth Part of that Expence. However, since they saw the Medica was as impatient of Grass as the Vineyards were, ’tis a Wonder they did not give it the same Culture with the Bidens, which would have been much better and cheaper, than to cleanse the Medica with Fingers. Indeed Fingers were made before the Bidens; but sure the Effect of its Use in raising Juices to the Vine, had inspired the Romans with more judicious Speculations, than to give that for a Reason why they ho’d the Medica with their Fingers, rather than with the Bidens.
Oh! But this was made with Iron, and Medica had, in those Times, an Antipathy to Iron; and after it was sown, the Place must not be touch’d by that Metal; therefore the Seed must not be cover’d with a Plough, nor with Iron Harrows. But if they had made Trials enough, to know that half an Inch was a proper Depth to cover this Seed at, these Virtuosi would have been convinc’d, that it had no less Antipathy to these Instruments, of what Matter soever they were made, if they bury’d it Five or Six Inches deep, which the Plough must do, and the Weight of Iron Harrows in such fine Ground not much less. Had the Plough been all of Wood, the Furrow would have lain never the lighter upon the Seed; and if the wooden Harrows had been loaded with a Weight capable of pressing it down as deep, it would have been no more able to rise, than if it had been buried with Iron Harrows: This Columella seems to be sensible of, when he says, Rastellis ligneis; viz. That it was not sufficient for them to be made of Wood, unless they were diminutive; for then they were light ones. ’Tis probable the Plough suffer’d none to come up, and the heavy Harrows very few, tho’ perhaps Plants enough, had they calculated what Number were sufficient: But unless the Ground were cover’d with them at first, it seems they had not Patience to wait till the Plants grew large enough, to fill it with a bare competent Number, and thought it not worth while to weed and water, what they fansied to be an insufficient Number. ’Twas expected that the Thickness of the Plants should help to kill the Grass: Yet upon due Observation ’tis found, that when their excessive Numbers have brought a Famine amongst them, they are forc’d to prey upon one another; and tho’ the stronger survive, yet even those are so weaken’d by Hunger, that they become the less able to contend with Grass, whose good Fortune it was, that Superstition would not permit the Romans to interpose, by attacking it with Iron Weapons.
I hope these Hints may be improv’d for the Abolition of old Errors, and for the Discovery of new Truths; to the end that Luserne may be planted in a more reasonable Method than has been commonly practis’d: And when the Theory is true, ’tis impossible the Practice should be false, if rightly apply’d; but if it fail of Success, the Event will be a Proof either of a Misapplication, or that the Theory is false.
Luserne should be order’d for Hay in the same Manner as is directed for St. Foin in the foregoing [Chapter]: But it must be observ’d, that Luserne is more worsted by being suffer’d to survive its Virginity before cutting; and therefore the richest and most nourishing Hay is cut whilst the Stalks are single, without any collateral Branches shooting out of them; and when they are so, neither Blossoms nor even their Buds appear. But of that sown in the old Fashion, the last Crops, for want of a new Supply of Nourishment, grow so slowly, that ere it is high enough to be cut, the Blossoms are blown out, and the Stalks, tho’ very small, are become woody, hard, and dry, and make the Hay nothing near so nourishing as that of the first Crops.
But in that which is ho’d, the last Crops of it will, by virtue of the greater Quantity of Nourishment it receives, grow faster, and be of an Height fit to cut before blossoming, and thence being as young and vigorous, make as good Hay as the first Crops; so that Hoeing does not only procure more and larger Crops, but also better Hay.
This is most certain, that unless we can keep our Luserne pretty clean from natural Grass, we cannot expect it to succeed, let the Soil be never so proper.
CHAP. XIV.
Of Change of Species.
I. That Plants of the most different Nature feed on the same Sort of Food.
II. That there is no Plant but what must rob any other Plant within its Reach.
III. That a Soil which is proper to one Sort of Vegetable once, is, in Respect of the Sort of Food it gives, proper to it always.