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Obfervations on the grafting of Trees. In a Letter from Thomas Andrew Knight, Efq. to Sir Jofeph Banks, Bart. from the Philofophical Tranf




AM encouraged to addrefs the following letter to you, by the opinion you were last year pleafed to exprefs. of part of my experiments and obfervations, on the difeafes and decay of thofe varieties of the apple and pear which have been long in cultivation. The difeafe, from whole ravages they fuffer moft is the canker, the effects of which are generally firft feen in the winter, or when the fap is firft rifing in the fpring. The bark becomes difcoloured in fpots, under which the wood, in the annual fhoots, is dead to the centre, and in the older branches, to the depth of the laft fummer's growth. Previous to making any experiments, I had converfed with feveral planters, who entertained an opinion, that it was impoffible to obtain healthy trees of thofe varieties which flourished in the beginning and middle of the prefent century, and which now form the largeft orchards in this country. The appearance of the young trees, which I had feen, juftified the conclufion they had drawn; but the filence of every writer on the fubject of planting, which had come in my way, convinced me that it was a vulgar error, and the following experiments were undertaken to prove it fo..

I fufpected that the appearance of decay in the trees I had feen lately grafted, arofe from the difeafed ftate of the grafts, and concluded hat if I took fcions or buds from 4

trees grafted in the year preceding. I should fucceed in propagating any kind I chofe. With this view, I inferted fome cuttings of the best wood

I could find in the old trees, on young flocks raised from feed. I again inferted grafts and buds taken from thefe on other young stocks, and, wifhing to get rid of all connection with the old trees, I repeated this fix years; each year taking the young fhoots from the trees laft grafted. Stocks of different kinds were tried, fome were double grafted, others obtained from appletrees which grew from cuttings, and others from the feed of each kind of fruit afterwards inferted on them; I was furprized to find that many of thefe ftocks inherited all the diseases of the parent trees.

The wood appearing perfect and healthy in many of my laft grafted trees, I flattered myfelf that I had fucceeded; but my old enemies, the mofs and canker, in three years convinced me of my mistake. Some of them, however, trained to a fouth wall, efcaped all their difeafes, and feemed (like invalids) to enjoy the benefit of a better climate. I had before frequently obferved, that all the old fruits fuffered leaft in warm fituations, where the foil was not unfavourable. I tried the ef fects of laying one kind, but the canker deftroyed it at the ground. Indeed I had no hopes of fuccefs from this method, as I had oblerved that feveral forts, which had always been propagated from cuttings, were as much difeafed as any others. The wood of all the old fruits has long appeared to me to poffefs lefs clafticity and hardnefs, and to feel more foft and fpongy under the knife, than that of the new varieties which I have obtained from


feed. This defect may, I think, be the immediate caufe of the canker and mofs, though it is probably itfelf the effect of old age, and therefore incurable.

Being at length convinced that all efforts, to make grafts from old and worn out trees grow, were ineffectual, I thought it probable that thofe taken from very young trees, raised from feed, could not be made to bear fruit. The event here an fwered my expectation. Cuttings from feedling apple-trees of two years old were inferted on flocks of twenty, and in a bearing ftatc. Thefe have now been grafted nine years, and though they have been frequently tranfplanted to check their growth, they have not yet produced a fingle bloffom. I have fince grafted fome very old trees with cuttings from feedling appletrees of five years old: their growth has been extremely rapid, and there appears no probability that their time of producing fruit will be accelerated, or that their health will be injured, by the great age of the ftocks. A feedling apple tree ufaally bears fruit in thirteen or four teen years; and I therefore conclude, that I have to wait for a blof fom till the trees, from which the grafts were taken, attain that age, though I have reafon to believe, from the form of their buds, that they will be extremely prolific. Every cutting, therefore, taken from the apple (and probably from every other) tree, will be affected by the ftate of the parent ftock.. If that be too young to produce fruit it will grow with vigour but will not blof om, and if it be too old it will immediately produce fruit, but will never make a healthy tree, and confequently never anfwer the in

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tention of the planter. The root, however, and the part of the flock adjoining it, are greatly more dura. ble than the bearing branches; and I have no doubt but that fcions obtained from either would grow with vigour, when thofe taken from the bearing branches would not. The following experiment will, at leaf, evince the probability of this in the pear-tree. I took cuttings from the extremities of the bearing branches of fome old ungrafted pear-trees, and others from feions which fprang out of the trunks near the ground, and inferted fome of each on the fame flocks. The former grew without thorns, as in the cultivated varieties, and produced bloffoms the fecond year; whilft the latter affumed the appearance of stocks just raised from feeds, were covered with thorns, and have not yet produced any bloffoms.

The extremities of those branches which produce feeds; in every tree, probably fhew the firft indication of decay; and we frequently fee (par ticularly in the oak) young branches produced from the trunk, when the ends of the old ones have long been dead. The fame tree, when cropped, will produce an almost eternal fucceffion of branches. The durability of the apple and pear, I have long fufpected to be different in dif ferent varieties, but that none of either would vegetate with vigour much, if at all, beyond the life of the parent flock, provided that died from mere old age. I am confirmed in this opinion by the books you did me the honour to fend me: of the apples mentioned and described by Parkinfon, the names only remain, and thofe fince applied to other kinds now alfo worn out; but many of Evelyn's are ftill well known,


This particularly the red-ftreak. apple, he informs us, was railed from feed by lord Scudamore in the We beginning of the laft century.* have many trees of it, but they appear to have been in a ftate of decay during the laft forty years. Some others mentioned by him are in a much better ftate of vegetation; but they have all ceased to deferve the attention of the planter. The durability of the pear is probably fomething more than double that of the apple.

It has been remarked by Evelyn, and by almost every writer fince, on the fubject of planting, that the growth of plants raifed from feeds was more rapid, and that they produced better trees than thofe obtained from layers or cuttings. This feems to point out fome kind of decay attending the latter modes of propagation, though the custom in the public nurseries of taking layers from ftools (trees cropped annually close to the ground) probably retards its effects, as each plant rifes immediately from the root of the parent stock.

Were a tree capable of affording an eternal fucceffion of healthy plants from its roots, I think our woods muft have been wholly overrun with thofe fpecies of trees which propagate in this manner, as thofe fcions from the roots always grow in the first three or four years with much greater rapidity than feedling plants. An afpin is feldom feen without a thousand fuckers rif ing from its roots; yet this tree is thinly, though univerfally, feattered over the wood-lands of this country. I can speak from experience, that the luxuriance and exceffive difpofi

tion to extend itself in another plant
which propagates itfelf from the
root (the rafpberry), decline in
twenty years from the feed. The
common elm being always propaga-
ted from fcions or layers, and
ing with luxuriance, feems to form
an exception; but as fome varieties
grow much better than others, it
appears not improbable that the
moft healthy are those which have
laft been obtained from feed. The
different degrees of health in our
peach and nectarine trees may, I
think, arife from the fame fource.
The cak is much more long-lived
in the north of Europe than here;
though its timber is lefs durable,
from the numerous pores attending
The climate of
its flow growth.

this country being colder than its
native, may, in the fame way, add
to the durability of the elm; which
may poflibly be farther increased by
its not producing feeds in this cli-
mate, as the life of many annuals.
may be increased to twice its natu-
ral period, if not more, by prevent-
ing their feeding.

I have been induced to fay a great deal more on this fubject than, I fear, you will think it deferves, from a conviction that immenfe advantages would arife from the cultivation of the pear and apple in other counties, and that the ill fuccefs which has attended any efforts to propagate them, has arifen from the ufe of worn out and diseased kinds. Their cultivation is ill understood in this country, and worse practised; yet an acre of ground, fully planted, frequently affords an average produce of more than five hundred gallons of liquor, with a tolerably good crop of grafs; and I have not

Probably about the year 1634.


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On the Dry-Rot in Timber; in a Letter from Robert Batfon, Efq. of Lime-Houfe, to the Society for the Encouragement of Arts, Manufactures, and Commerce; from whofe Franfuctions it is extracted.

HE fociety for the encourage

In the autumn of the year 1786, the clofet was locked up about ter weeks; on opening it, numerous fungi were obferved about the low. er part of it, and a white mould was spread by a plant resembling a vine or fea-weed, and the whole of the infide, China, &c. was covered with a fine powder of the colour of brick-duft. It being then cleaned out, I foon perceived (what indeed I did not expect) that the evil had impregnated the wood fo far as to run through every fhelf therein, and the brackets that fupported them; it had alfo feized upon, and deftroyed, a movable board for breaking fugar on. I therefore, in the beginning of the year 1787, determined to ftrip the whole clofet of lining and floor, and not leave a par ticle of the wood behind; and also

THE for encourages, to dig and take away about two feet

and commerce, continuing to offer a premium for difcovering the caufe of the dry-rot in timber, and difclofing a certain method of prevention, I beg leave to lay before them an account of a method I have put in practice, and which, at prefent, appears to me to have fully fucceed


The dry-rot having taken place in one of my parlours, in fuch a manner as to require the pulling down part of the wainscot every third year, and perceiving that it arofe from a damp ftagnated air, and from the moisture of the earth, I determined, in the month of June, 1783, to build a narrow clofet next the wall through which the damp came to the parlour, which had the defired effect; but, though it put a total stop to the rot in the parlour, the evil foon appeared in the clofet; fungi of a yellow colour arofe, to a great degree, in various parts of it,

of the earth in depth, and leave the walls to dry, fo as to deftroy the roots or feeds of the evil. When, by time, and the admiffion of air, and good brufhing, it had become fufficiently dry and cleansed; I filled it, of fufficient height for my joifts, with anchor-fmiths afhes; knowing that no vegetable would grow in them. My joifts being fawed off to their proper lengths, and fully prepared, they and their plates were well charred, and laid upon the athes; particular directions being given that not any fcantling or board might be cut or planed in the place. left any duft or fhavings might drop among the afhes. My flooring boards being very dry, I caufed them to be laid clofe, to prevent the dirt getting down, which, I thought, in a courte of time, might bring on vegetation.

The framing for lining the closet was then fiixed up, having all the


lower pannels let in to be faftened with buttons only; that, in cafe any vegetation should arife, the pannels might, with ease, be taken out to examine them.

This having now been done upwards of fix years, and no vegitation or damp appearing, the whole of the pannels and floor remaining in the fame ftate as when first put in, I shall have a fatisfaction in taking part of the floor up, if the fociety think proper to appoint a committee to examine the place.

If what I have produced meets the approbation of the fociety, I with it made public under their fanction, that as full a trial as poffible

may be made of it; and if, at a proper diftance of time, it proves of general utility, any honourary token of the fociety's approbation will be received with much fatifaction by me.

I think it may be highly neceflary, n fome fituations, to take out a greater depth of earth; and where thes can be had from a foundery, they are fully equal to thofe from anchor-fmiths, but by no means depend upon houfe-afhes. I am, &c.


In confequence of the foregoing etter, a committee was appointed examine and report the state of be closet, who met on the 15th of May, 1794; the wainscot being taten down, and the flooring-boards aken up, they were all found enrely free from any appearance of the rot; and, from all the circumftances then obferved, it was the opinion of the committee, that the method advifed by Mr. Batfon,

when fully and completely put in execution, appeared to have anwered every intention mentioned in his letter; and this opinion feemed the more juftly founded, as two pieces of wood (yellow fir) which had been driven into the wall as plugs, without being previously charred, were affected with the rot.

Compofition of a Water which has the Property of Deftroying Caierpillars, Ants, and other Infects; invented by C. Tatin,* at Paris; from the Annals de Chimie.

AKE of black foap, of the best




flowers of fulphur, -mushrooms, any kind, 2lb. -river or rain water, 15 gls. Divide the water into two equal parts; pour one part, that is to fay, feven gallons and a half, into a barrel, of any convenient fize, which fhould be ufed only for this purpofe; let the black foap be stirred in it till it is diffolved, and then add to it the mushrooms, after they have been flightly bruifed.

Let the remaining half of the water be made to boil in a kettle; put the whole quantity of fulphur into a coarse open cloth; tie it up with a packthread in form of a parcel, and faften to it a stone or other weight, of fome pounds, in order to make it fink to the bottom. If the kettle is too small for the feven gallons and a half of water to be boiled in at once, the fulphur must alfo be divided. During twenty minutes (being the time the boiling fhould continue) ftir it well with a

* The Bureau de Confultation of Paris gave a reward to the author of this composition for lus difcovery, which they defired might be made as public as poffible.

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