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NEW ENGLAND FARMER. 



DISEASE IN PEAR TREES. 

 We have heard complaints that the Pear Trees of 

 some of our best cultivators in the vicinity of Boston 

 are ia a perishing condition, from some cause or causes 

 not ascertained, and perhaps not ascertainable. The 

 trees have been thoroughly examined, and sawed into 

 small pieces, with the hope of detecting the destroyer 

 in some insect, which might escape common observa- 

 tion. We think it not improbable that the following 

 article may furnish a clue to the mystery. Perhaps 

 some people kill their pear trees, in the same way that 

 some spoil their children, by too much kindness. At 

 any rate we should think it advisable to try what would 

 be the effect of lellmg Ihem alone, and see if less tr 

 ming and manuring may not be attended with benefi- 

 cial consequences. We do not know but trees as well 

 as animals may die of surfeits, or, as a medical man 

 would say, might be subject to plethora. If there 

 is more nourishment received by the roots than the 

 branches can dispose of, the trees (in a free govern- 

 ment) will take the liberty to die, let science say what 

 it will on the subject. To be sure they may not die 

 .lecundum arletn, but still if they are doctored off they 

 will as surely come to an end as if they had been starv- 

 ed for want of manure. We apprehend that pear trees 

 as well as peach trees partake a little of the nature of 

 Hebrew roots, which Butler says 



-" Are always found 



To flourish best on barren ground. 

 But, we do not pretend to be positive about this mat- 

 ter ; we only suggest the thing for consideration ; and 

 iCour views are erroneous, shall be happy to stand cor- 

 rected. — Editor A". E. Farmer. 



From the American Farmer. 



Elmwood, Jan. 1st, 1821. 



The great disappointment that has attended 

 the cultivation of the finer kinds of the pear 

 has been matter of much regret, with all the 

 lovers of this delicious fruit. And some who 

 were most forward to obtain Ihera and most par- 

 ticular in nursing' them, have utterly despaired 

 from a consciousness of their great attention to 

 them, and knowledge of general failure. But 

 let us remember, that a similar despair prevail- 

 ed respecting grapes, which is now done away 

 by actual cultivation. 



The object of this paper is not only to in- 

 quire theoretically into the cause of the most 

 common disease that assails them ; but to pro- 

 duce actual facts, which must convince the mind, 

 the most sceptical, of the practicability of re- 

 taining these fine fruits, and that by means level 

 to the capacity of every one. 



The principal disease that affeete them, and 

 the one I particularly allude to, consists ia a 

 withering of the interior bark, especially of the 

 limbs, appearing in spring in spots and bars, 

 and more extended affections of the same 

 kind, spreading to the destruction oftheindi- 

 Tidual limb, though the superior part of the 

 limbs are often unaffected by the disease, and 

 are only destroyed by being cut off from the 

 juices of the main stock. As I know ot no ani- 

 nml disease exactly resembling it in cause and 

 effect more than Kibes, which consists in cold 

 overtaking a high circulation, and throwing off 

 the skin to perish, I shall call it by that name, 

 to distinguish it from the very improper appel- 

 lation, blast, which is applied to trees killed 

 simply by severity of cold or heat. 



In all the various suggestions as to the cause 

 of this disease, 1 never heard of one that came 



near to the fact, which is more to be wondered 

 at as the real cause has been so strongly index- 

 ed by notorious facts. Such for instance, as 

 hard winters, with long cold springs, giving us 

 good pears and leaving us sound trees, whilst a 

 warm winter and especially a warm February, 

 followed by a cold March, (a thing almost inev- 

 itable,) destroys our trees. We have long 

 been acquainted with this much of vegetable 

 physiology that the bark (as the juices fail and 

 the fall comes) forms on its interior surface lon- 

 gitudinal fibres the same as sap wood, and by 

 this means adheres to the main sapwood, becom- 

 ing one and inseparable — and that when a cer- 

 tain temperature, say^that of April, becomesstea- 

 dy, that those very same fibres having lost their 

 color and become maternal, throw out juices and 

 form fibres differently disposed and colored, or 

 Lark. Just as we see on denudating a chesnut-tree 

 when the sap is running, a new bark is formed 

 by light and heat acting on those juices, and 

 giving them a form and color different from 

 what would have ensued if excluded from light 

 and heat.* 



It would, therefore, seem to be the order of 

 nature, that a free could not otherwise exist in 

 severe cold weather, but by this union of bark 

 to the sapwood. This partial retrocession of 

 juices and unity of the parts — a separation at 

 such time, would be as certain to produce inju- 

 ry and death of the bark, as evolving its fruit buds 

 would annihilate the fruit of the next season. 



It appears, that light and heat with the con- 

 sequent flow of juices by continuing to act on 

 the organic matter of the tree, would form in 

 the first or lowest degree of circulation, the 

 above named longitudinal fibres of sapwood — in 

 the next degree bark, in a higher degree leaves 

 and buds of different kinds, by a still high tem- 

 perature the wood buds would be elongated 

 into branches, and by the greatest degree fruit 

 buds into blossoms, germ fruit — every one of 

 these operations seem more and more exter- 

 nal or exposed, as if the tree with consciousness 

 of her safety and the sun's approach, had suc- 

 cessively unfolded her inmost recesses of beauty 

 and usefulness; falling back in the same order 

 with the retiring season— that which was last, 

 falling ti»st — till all has retreated into winter 

 quarters. 



It is a well known fact, that the finer kinds 

 of pears are introduced from a milder clima/e 

 than 39 degrees (from France,) and therefore, 

 are very sensible to both cold and heal. They 

 are trees that abound with juices, as may be 

 seen by the numerous scions that they fling up 

 around them. If the latter part of winter, or 

 early, spring is warm, these juices are set atloat, 

 especially if the ground is rich and cultivated. 

 In this degree of light and heat the bark begins 

 to form, a separation to take place from the 

 new made sapwood, and in a few days, winter 

 returns upon the tree, or in other words, Febru- 

 ary has been spring and March winter — an im- 

 perfect hark is thus separated from the mother 

 white wood, and like the untimely, weaned 

 child, it sickens, it droops, and as heat is far- 

 ther applied, the damage increases till it dies, 



*It appears that the sapwood in the plantule makes 

 the first bark, as may be seen on the young Melia, and 

 then does the otiice occasionally to supply the deficien- 

 cy by accidents whilst the bark ever after annually 

 makes sapwood, and increases the size of the tree with 

 a visible addition. 



because this heat evaporates the juices fasti 

 than it can force them into the contracted v« 

 sels — which perhaps never can be made to t 

 pand again in the vegetable, whatever mayti 

 done in the animal economy.* 



It is highly probable, that north of this (m 

 Maryland) many trees die of winter cold, * 

 excessive retrocession of the juices may becoj 

 fatal, the bark may give way and split. Tl 

 is often the case with exotic shrubbery, and 

 is remarkable, that they always give way it 

 the trunk, where the bark is less elastic at 

 scurfy. It will, therefore, be easy to distingai 

 this disease, which is more properly a bla 

 from Kibes — and moreover, it requires a ve 

 different treatment. Manuring articles ma 

 into a paste and spread on the body and larg 

 limbs with a sedge broom, will be a great ( 

 fence where matting is not to be had — such H 

 instance as white wash, thickened with asb 

 and soft cow dung. But in the disease 1 h» 

 been describing, it might be the very cause 

 death. 



Let us now proceed to matter of fact ; I kni 

 of only two sels of healthy pear trees, they ha 

 in five or seven years changed owners. In t 

 time of the former owners, much attention » 

 paid to them and the disease was constant. T. 

 present owners neither manure nor dig abo 

 them. In one of these, 1 know that the gn 

 has surrounded them unbroken for years, a 

 they are not only perfect but bear fruit, wh 

 all others fail — they are Bergamot. In theol 

 er set alluded to more attention is paid, t 

 grass is cleared away in early summer, I 

 tbe shoots are permitted to grow for forty ft 

 around them in such quantity, as to defy a 

 removal but with a scythe, and these remain i 

 next grass time — no manure is applied and J 

 ground naturally poor. Even the unhealt 

 trees have shot out new and healthy branch 

 since they have remained undisturbed : tht 

 facts are too plain to be misunderstood, th 

 point out the remedy as well as the manner 

 the remedy acting. The abundant juices a 

 restrained in the first case, which is preferab 

 and in the latter they are partly restrained a 

 partly diverted into young scions. 



1 will mention two other facts, though not 

 plain, yet they confirm the above. 1 moved 

 a place where there vvere two very healthy pe 

 trees, (Vergolieu,) one was choked as 1 tboug 

 with grass, the other was so surrounded wi 

 scions as scarcely to admit approach. I reraovi 

 the scions, dug and manured the ground 

 both, and the consequence soon ensued ; I lo 

 them by Kibes. The other case that confirii 

 those opinions and facts, was that of a gardem 

 of my acquaintance, who was actually on tl 

 right track to save his trees, but for want of n 

 derstanding the true cause of the disease Ij 

 failed — he discovered that the trees which hii 

 honey suckles around them, were less liable'! 

 disease ; but he supposed it were protectioij 

 and therefore manured and dug, and thus d«| 

 the grave of his fine trees. [ 



Let us therefore suffer our trees, after the! 

 have come near the fruit bearing period to ve| 

 etate naturally — they will be a little more tai 

 dy in growing up, but they will be har«|j 



* It is sometimes the middle of summer belore 111 

 whole damage is developed, and some imptrCtct fit 

 forming, has led those who merely take a peep at It 

 tree, to conclude it to be done at this time. 



