Part 21

’Tis therefore necessary, that our Rows be plac’d at such a Distance, as that their Intervals may be wide enough for the Hoe-plough to raise an artificial Pasture, sufficient to sustain the Number of Plants in them.

Whoever shall make Trials of this Husbandry (for that is all I propose to others), I would advise them to begin with Rows that have Intervals of Thirty-three Inches; for, if they begin with much narrower Distances, they may be by that means disappointed of Success: But tho’ they should afterwards find a Way to hoe them at somewhat nearer Distances; yet the Loss of a few Perches of Ground would not be much; neither can they be wholly lost, since the Roots of these Plants may be prov’d to extend much farther horizontally, than from Row to Row at that Distance. And the wider the Intervals are, the more Earth will be till’d in a Perch of Ground; because Six Rows, which will be therein at Thirty-three Inches Distance, will admit the Hoe-plough to till more Earth, than Nine Rows at Twenty-two Inches Distance from each other: And, besides, ’tis not proper, that every time of hoeing, the Plough should come very near to the Plants, unless when Grass comes amongst them; and then they may, in Thirty-three Inch Spaces, be perfectly cleansed in this manner: _viz._ Plow a good Furrow from each Side of every Row; and then with Harrows, or other Instruments proper for that Purpose, going cross them, you will pull out both Earth and Grass from betwixt the Plants; then, after a convenient Time, plow these Furrows back again to the Rows; this will in a manner transplant the upper Part of the Roots, and bury the Grass, tho’ it be not dead, by lying open to be dry’d by the Sun: Then harrow the Ground to break it more, and to level it, and go once over it with a very light Roller, to the End that the Hay may be raked up the cleaner.

I am aware of the common Prejudice, which is, that People, when they have never seen a Plantation of these Plants in Perfection, are apt to form to themselves the Idea of such small ones as they have been used to see; and thence imagine it impossible that this (tho’ a double) Number should be sufficient to make a Crop. But they might, with equal Reason, imagine the same of Apple-trees at a Year’s Growth, which are less than these at the same Age; and so plant a Thousand Trees in the Room proper for one. The Antients direct the Planting of Seventeen _Cytisus_ Plants in a Perch of Ground; and I do not believe, that ever those Seventeen could yield a Crop equal to Two hundred Twenty-four Luserne-plants; for as many Ounces of Hay as each of these yields, so many Ton of Hay will one Crop of an Acre produce: Thus by weighing the Product of one Plant (supposing them all equal) the Quantity of the Crop may be determin’d, and prov’d greater than Fancy from their Number represents.

_s._ _d._ _April_ 14. One single unho’d Plant of Luserne had Thirty-one Stalks, which, by Silver-Money, weigh’d green 23 0 24. The same dried to Hay, weigh’d 6 6 14. The Stalks of one single ho’d Luserne-plant green, weigh’d 56 0 24. The same dry’d 14 6 14. Eighteen Inches in Length of a Row, being five indifferent Plants, weigh’d green one Pound and an half _Avoirdupois_ 24. Dry’d to Hay, it weigh’d 28 6 25. One Foot of an ho’d Row, being One hundred and Sixty Stalks of two Luserne Plants of Six or Seven Years old, weigh’d Two Pound green But the same dry’d, to the 9th of _May_, weigh’d no more than 31 6 Which last is about Three Tons to an Acre.

This I am certain of, that the least competent Number of Plants will bring the greatest Number of Crops: since I see the Stalks of a single ho’d Plant grow higher in Fifteen Days, than one amongst near Neighbours does in Thirty Days.

The greatest Difference between the Culture of this and St. Foin is, that Luserne Rows should be more grown, before the Plants be made single in them by the Hand-hoe, lest the Fly should destroy some afterwards, and then they might become too thin. For Luserne is sometimes eaten by the Fly, as Turneps are, tho’ St. Foin be never liable to that Misfortune, if sown in a proper Season. Luserne must also be more frequently ho’d[200], in some Proportion to the more frequent Crops it produces.

[200] The Hoe-plough is the Instrument to bring it to Perfection: but then I doubt it must lie still some Years, lest the plow’d Earth injure the Hay that is made upon it; and when it is come to a Turf, and the Luserne wants renewing, the Four coulter’d Plough is the only Instrument that can prepare the Turf to be kill’d, and cure the Luserne; which Plough must be used in the following Manner: Turn its Furrows toward one Row, and from the next; that is, plow round one Row, and that will finish Two Intervals, and so on; and the next Plowing must be towards those Rows, from whence they were turn’d the first time; take care the first Furrows do not lie long enough on the Rows to kill the Plants, which will be much longer in Winter than in Summer. But you may leave every Third or Fourth Interval unhoed for making the Hay on, which will be yet more beneficial, if the Swarths in mowing should fall thereon. This unhoed Interval may be plowed when there is Occasion, and another left in its stead.

I shall not go about to compute the Difference of Expence bestow’d in the _Roman_ Culture and in this; yet it will appear theirs was incomparably more chargeable, and that the Excess of Charge was occasioned by their Error in the Theory of Husbandry.

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._

If any one of these _Three Propositions_ be true, as I hope to prove all of them are, then it will follow, that there is no need to change the Species of _Vegetables_ from one Year to another, in respect to the different Food the same Soil is, tho’ falsely, supposed to yield[201].

[201] For if all Plants rob one another, it must be because they all feed on the same Sort of Food; and, admitting they do, there can be no Necessity of changing the Species of them, from one Soil to another; but the same Quantity of the same Food, with the same Heat and Moisture which maintains any Species one Year, must do it any other Year.

The common Opinion is contrary to all these (as it must be, if contrary to any one of them): And since an Error in this fundamental Principle of _Vegetation_ is of very ill Consequence; and since Dr. _Woodward_, who has been serviceable in other respects[202] to this Art, has unhappily fallen in with the Vulgar in this Point; his Arguments for this Error require to be answer’d in the first Place.

[202] By proving, in his Experiments, that Earth is the _Pabulum_ of Plants.

The Doctor says[203] ‘It is not possible to imagine how one uniform, homogeneous Matter, having its Principles, or original Parts, all of the same Substance, Constitution, Magnitude, Figure, and Gravity, should ever constitute Bodies so egregiously _unlike_, in all those Respects, as Vegetables of different Kinds are; nay, even as the different Parts of the _same_ Vegetable.’

[203] In _Philos. Trans._ No. 253.

‘That there should be that vast Difference in them, in their several Constitutions, Makes, Properties, and Effects, and yet all arise from the very same Sort of Matter, would be very strange.’

_Answer._ ’Tis very probable, that the terrestrial Particles which constitute _Vegetables_, tho’ inconceivably minute, may be of great Variety of Figure, and other Differences; else they could not be capable of the several Ferments, _&c._ they must undergo in the Vessels of Plants. Their Smalness can be no Objection to their Variety, since even the Particles of Light are of various Kinds.

But as the Doctor asserts, ‘That each Part of the same _Vegetable_ requires a peculiar specific Matter for its Formation and Nourishment; and that there are very many and different Ingredients to go to the Composition of the same individual Plants;’

From hence must be inferred, that the same Plant takes in very many and different Ingredients (and it is proved, that no Plant refuses any Ingredient[204] that is capable of entering its Roots. Tho’ the terrestrial Particles which nourish _Vegetables_, be not perfectly homogeneous; yet most of the various Tastes and Flavours of Plants are made in and by the Vessels[205].

[204] Dr. _Grew_, in his Anatomy of Plants, by microscopical Inspection, found, that the outer Superficies of Roots was of a spongy Substance; and ’tis well known, that no such Body can refuse to imbibe whatever Liquor comes in Contact with it, but will by its springy Porosity absorb any sort of Moisture.

[205] We are convinced, that ’tis the Vessels of Plants that make the different Flavours; because there is none of these Flavours in the Earth of which they are made, until that has enter’d and been alter’d by the vegetable Vessels.

Doctor _Woodward_ says, ‘That Water will pass Pores and Interstices, that neither Air, nor any other Fluid, will: This enables it to enter the finest Tubes and Vessels of Plants, and to introduce the terrestrial Matter, conveying it to all Parts of them; whilst each, by means of Organs ’tis endow’d with for the Purpose, intercepts, and assumes into itself, such Particles as are suitable to its own Nature[206]; letting the rest pass on _through the common Ducts_.’

[206] If the Doctor’s Plants were so nice in leaving vegetable Matter _behind, quiet and undisturb’d_, ’tis a Wonder they would take up the mineral Matter, as, he says, they did, that kill’d themselves with Nitre.

These Plants might, with much less Difficulty, have distinguish’d the mineral Matter from the vegetable Matter, than they could distinguish the different Particles of vegetable Matter from one another, and must have been very unwise to chuse out the Nitre (their Poison) from the Water and Earth, and to leave the vegetable Particles behind; none of which could be so improper to them as the Nitre.

It may perhaps be objected, that such like pernicious Matter kills a Plant by only destroying its Roots, and by closing the Pores; which prevents the Nourishment from entering to maintain its Life; and that such Matter doth not itself enter to act as Poison upon the Sap, or upon the Vessels of the Body, or Leaves: But it plainly appears that it doth enter, and act as Poison; for when some of the Roots of a Mint, growing in Water, are put into salt Water, it kills the whole Plant, although the rest of the Roots remaining in the fresh Water were sufficient to maintain it, if the other Roots had been cut off at the Time they were removed into the Salt Water; and also all the Leaves, when dead, will be full of Salt.

Or if the Juice of wild Garlick-seed be made use of instead of the salt Water, it will have the same Effect; and every one of the Mint-leaves will have a strong Taste of Garlick in it.

Here then he says plainly, That each Plant receives the terrestrial Matter in gross, both suitable and unsuitable to its Nature, retains the suitable Particles for its Augment, and the unsuitable lets pass through it. And in another Place he says they are exhal’d into the Atmosphere.

And this will appear to be the true Case of Plants; and directly contradicts what he advances, in saying, ‘That each Sort of Grain takes forth that peculiar Matter that is proper for its own Nourishment. First, the Wheat draws off those Particles that suit the Body of that Plant, _the rest lying all quiet and undisturb’d the while_. And when the Earth has yielded up all them, those that are proper for Barley, a different Grain, remain still behind, till the successive Crops of that Corn fetch them forth too; and so the Oats and Pease in their turn, till, in fine, all is carried off.’

In the former Paragraph he says, each Plant _lets pass through it_ the rest of the Particles that are not suitable to its own Nature. In the latter Paragraph he says, That each _leaves_ the unsuitable _all behind_ for another Sort; and so on.

Both cannot be true.

If the latter were true, Change of Sorts would be as necessary as it is commonly thought. But if the former be true, as I hope to prove it is, then there can be no Use of changing of Sorts in Respect of different Nourishment.

If in this Series of Crops each Sort were so just as to take only such Particles, as are peculiarly proper to it, letting all the rest alone to the other Sorts to which they belonged, as the Doctor imagines; then it would be equal to them all, which of the Sorts were sown first or last: But let the Wheat be sown after the Barley, Pease, and Oats, instead of being sown before them, and then it would evidently appear, by that starv’d Crop of Wheat, either that some or all of those other Grains had violated this natural Probity, or else that Nature has given to _Vegetables_ no such Law of _Meum_ and _Tuum_[207].

[207] A Charlock could not rob a Turnep, and starve it, more than several Turneps can do, unless the Charlock did take from it the same Particles which would nourish a Turnep; and unless the Charlock did devour a greater Quantity of that Nourishment than several Turneps could take.

Flax, Oats, and Poppy, could not burn or waste the Soil, and make it less able to produce succeeding Crops of different Species, unless they did exhaust the same Particles which would have nourish’d Plants of different Species: For let the Quantity of Particles these Burners take be never so great, the following Crops would not miss them, or suffer any Damage by the Want or Loss of them, were they not the same Particles which would have nourished those Crops, if the Burners had left them _behind, quiet and undisturbed_. Neither could Weeds be of any Prejudice to Corn, if they did draw off those Particles only that suit the Bodies of Weeds, _the rest lying all quiet and undisturbed the while_. But constant Experience shews, that all Sorts of Weeds, more or less, diminish the Crop of Corn.

If these Things were, as the Doctor affirms, why do Farmers lose a Year’s Rent, and be at the Charge of fallowing and manuring their Land, after so few Crops; since there are many more Sorts of Grain as different from these and one another, as those are which they usually sow?

They still find, that the first Crops are best; and the longer they continue sowing, the worst the last Crops will prove, be they of never so different a Species; unless the Land were not in so good Tilth for the first Crop as for the subsequent; or unless the last sown be of a more robust Species.

This Matter might be easily clear’d, could we perfectly know the Nature of those supposed _unsuitable_[208] _Particles_; but, in Truth, there is no more to be known of such of them, than that they are carried away by the Atmosphere to a Distance, according to the Velocity of the Air; perhaps several Miles off, at least, never like to return to the Spot of Ground from whence the Plants have raised them.

[208] But we must not conclude, that these Particles, which pass through a Plant (being a vastly greater Quantity than those that abide in it for its Augment), are all unsuitable, because no one of them happens to hit upon a fit _Nidus_: For since the Life of Animals depends upon that of Plants, ’tis not unreasonable to imagine, that Nature may have provided a considerable Overplus for maintaining the Life of individual Plants, when she has provided such an innumerable Overplus for continuing every Species of Animals.

But suppose these cast-off Particles were, when taken in, unfit for the Nourishment of any manner of Vegetables: Then the Doctor must fansy the Wheat to be of a very scrupulous Conscience, to feed on these Particles, which were neither fit for its own Nourishment, nor of any other Plant; and at the same time to forbear to take the Food of Barley, Pease, and Oats, letting that _lie still and undisturb’d the while_, as he says it does, tho’ he gives no manner of Reason for it.

’Tis needless to bring stronger Arguments, than the Doctor’s Experiments afford, against his own vulgar Opinion, of Plants distinguishing the particular Sort of terrestrial Matter, that, he says, is proper to each Sort of _Vegetable_, in these Words; _viz._ ‘Each Sort takes forth that peculiar Matter that is proper for its own Nourishment, the _rest lying all quiet and undisturb’d the while_.’