NEW ENOI-AI^D FARMER. 



Published by John B. Russell, at Mo. 52 JVorth Market Street, (at the Agricxdtural Warehouse). — Thomas G. Fessenden, Editor. 



VOL. YIII. 



BOSTON, FRIDAY, SEPTEMBER 11, 1829. 



No. 8. 



AGRICULTURE. 



fThe following is an able article on a very interest- 

 and important subject ; but wlietlier the author's 

 S ry is correct, wo shall not attempt to decide. Wc 

 »'l|nclined, however, to the belief, that those who attrib- 

 the sudden, and sometimes almost instantaneous 

 erin'r of a vigorous branch of a fruit tree, to the 

 )m of a very small insect, have not discovered a 

 ,e adequate to tlie supposed effect. 



Editor of N. E. F.irmer. 



BLIGHT IN PEAR TREES, &c. 



Xlract of a lelicr from a friend in New Jersey to ll.e Edi- 



iJl" the N. E. Farmer.] 



What Mr Bucl says of the fire blight is not so 



elusive to my apprehenyioii, as arc his remarks 



lie girdling protubeMiices which have hither- 



eeii so destructive to the Plum and ]MorelIo 



rry. lie is not alone in attributing the disease 



ed Jtre blight, to the venom ejected from an 



ct ; but, much as I should like to see this doc- 



itie established, I cannot admit it for a moment. 



n fully aware that a sin|;le drop of poison, in- 



nced into the animal system, will decompose 



fluids and cause death, whether it he injected 



ik rabid animal or by an enraged reptile. And 



ve no doubt but that if a sufficient quantity 



Id be forced into the circulation of a plant, 



the whole mass would he rendered unfit for 



uses to wliich the sap is destined. I have 



Ti le various experiments on the young and old 



iches of pear trees, but although T used the 



;rent poisons in a concentrated and diluted 



1 such asprussic acid — nitric acid — muriatic, 



as well as croton oil, and mercury, in several 



IS and although I sacrificed many an insect, 



1 as poisonous spiders, &c., yet I never suc- 

 led in injuring the tree farther than an inch or 

 above and below the inincture. We know 

 the rupture of a blood vessel, by a determina- 

 of blood to the head, will cause instant death 

 lan, and that this is often effected by external 

 lence, such as exposure to the sun. Here is an 

 logous case as it rcs|)ects loss of vital princi- 

 and the cases approach as nearly as the na- 

 of animal and vegetable life can appro.x- 

 :e. 



n exotic pear, such as the Vergalouse, the 

 nk, the St. Germain, or the D'Auche, grows 

 luxuriantly in our climate. They have the 

 ti icity of attracting a greater quantity of fluid 

 « iment than those trees which are indigenous, 

 fire blight occurs more frequently after a 

 mer shower in July or August, and during the 

 ihine. A shower falling on ally plant, while 

 sun shines fiercely, is always more or less in- 

 us. It has been my object for many years, 

 iceitain the cause of this destructive disease, 

 vigilant as I have been, and still am, I have 

 ir yet detected any insect in the act of puuc- 

 ig the tree so as to cause fire blight, although 

 _ lie actually seen the end of a limb perish with 

 hli°'ht before my eyes while examining it. I 

 '! ( stood under the shade of a fine St. Germain, 

 e I was directing my gardener how to ampu- 

 the limb of a similar tree which stood about 

 feet from me ; I discovered the blight imrae- 

 ily after one of those hot showers ; and, as 

 y constant practice, I hastened to the tree 



that the injured limb might be instantly separated. 

 Whilst I .stood under the St. Germain before 

 mentioned, my eye rested on the horizontal 

 branch before me, and to my surprise I saw the 

 leaves change color, from a dingy yellow to a 

 dark brown ! I had the limb cut off far below 

 the blight, and saved the tree, as I did the one 

 opposite to me. 



We all know that the blood of animals under- 

 goes a change as soon as it comes in contact with 

 the atmosphere. It not only becomes altered in 

 its nature, but it coagulates. The introduction of 

 atmospheric gasscs produces this result. So like- 

 wise with respect to the albumen or white of an 

 e^g. The substance certainly is completely 

 changed by the mere presence of heat, but what 

 new ]>rinciple of matter is gained by the opera- 

 tion, is, and will be for ever unknown. While the 

 sap of plants is confined within the proper vessels, 

 it possesses the healthful qualities necessary to it, 

 but if a rupture takes place at the tender exti'em- 

 ities of a limb, or, should no rupture occur, but 

 merely a detention or congestion of sap be the 

 consequence of the powerful rarification which 

 the hot, moist atmosphere causes, the sap, by 

 coming and remaining more immediately in con- 

 tact with external gasses, will acquire deleterious 

 qualities wholly unfit for the uses of the plant. 

 Every compound fluid undergoes a marked 

 change when exposed to the air. Crystals be- 

 come deliquescent, and fluids are crystallized ac- 

 cording to the amount of chemical agents which 

 are present in the atmosphere. If the sap of 

 plants, by the detention of its particles at the ex- 

 tremities, becomes glutinous, or acrid, or otherwise 

 vitiated, the returning vessels are no longer suited 

 to receive it. 



Perhaps the tender and extremely delicate liga- 

 ments which unite the different vessels, are de- 

 composed by the acrid principle which the de- 

 scending sap has acquired. Certain it is that the 

 parts which arg overflowed by the vitiated sap 

 have the appearance of being excoriated. Ow- 

 ing to our imperfect knowledge of the structure 

 of plants, we cannot ascertain whether any of the 

 vessels be ruptured, as in cases of congestion 

 in the animal system, or whether any of the ad- 

 hesive membranes be decomposed. If we ma- 

 cerate the back and leaves of a blighted limb, in' 

 water, for six hours, an_d likewise macerate the 

 hark and leaves of a healthy limb for the same 

 space of time, we shall find that the acrid j)rinci- 

 plc is more active and in greater abundance in the 

 water in which the diseased parts were immersed, 

 than in the other. There is therefore an excess 

 of acid in the virus which excoriates the inner 

 surface of the bark. A concentrated acid seems 

 to be the base of all poisons, but they do not all 

 necessarily emanate from the animal creation, 

 whether dog, snake or insect. 



We rely much on the instinct of inferior ani- 

 mals and insects for our safety. A rabid animal 

 inflicts a wound, not from instinct, but from the 

 absence of all sagacious sensation. He is in the 

 delirium of fever. Not so with a snake or spider. 

 It is the instinct of self-preservation, self-defence, 

 or revenge which prompts them to inflict a wound. 

 The instinct of animals including all that have 



lo:omotive powers, is seldom at fault in matters 

 which" concern the continuance of their species. 

 The locust, the beetle, the pea-bug, the curculio, 

 and a number of others, puncture the bark and 

 the fruit of trees and vegetables for the purpose 

 of depositing their eggs, or to sustain life. The 

 vine fretter and a number of the cater])illar tribe, 

 abstract by suction, the juices of the leaves, and 

 thus paralyze the leaf. But although this ulti- 

 mately endangers the life of the plant, still it is 

 done by the ordinary means of injuring the respir- 

 atory organs. We do not think that any insect is 

 endowed with a virus which is so desolatin^in its 

 eflccts as to produce the disease called fire bhght, 

 or if it be possessed of so deadly a poison that it 

 would expend it gratuitou.sly on the unoffending- 

 bark of a tree. An insect could have no possible 

 motive for ejecting its poison unless it had a pros- ■ 

 pect of present or future gratification. 



J^ative pears arc ven/ seldom touched by this mala- 

 dy, because, in our apprehension, the sap vessels 

 are capable of resisting the various changes of 

 our atmosphere. This is not the case, however, 

 with all of our fruit trees, even of tliose which 

 have for centuries been acclimated. The quince 

 trees, for instance, are attacked by a sjjecies of fire 

 bliglit, which often injures them very materially; 

 and I have seen the j'oung wood or twig of the 

 apple tree scathed as if by lightning. In truth 

 the electric fluid seems to be the most likely 

 agent to produce a phenomenon of the kind. 

 When the air is charged with electric matter, the 

 acetous fermentation of vegetable fluid is more 

 active, and they undergo a change at such time?. 

 This is a fuct well known even to the ignorant, 

 who usually attribute it to t<hunder. I have re- 

 peatedly tasted the liquor in which the blasted 

 limbs and leaves of the pear tree have been steep- 

 ed, and I have as often chewed the inner and 

 outer bark of the diseased parts. I have done 

 this for the purpose of ascertaining the difference 

 in taste of the sound and unsound parts. I never 

 received any injury by so doing, nor did any virus 

 get into the circulation, when a man's hand, hav- 

 ing a fresh cut on it. was plunged for some time 

 in the water containing the dead branches. 



Congestion does not always take place at the 

 extremities of all plants. In the cherry and plum 

 tree it is confined entirely to the bark of the trunk 

 or to the thickest parts of the principal limbs; and 

 unless the ruptured spots be immediately cut out, 

 the sap will excoriate the surrounding parts to 

 great extent. Tall trees are more subject to this 

 disease of the bark, than those which have short 

 bodies or trunks. It proves therefore that a highly 

 rarified atmosphere, accompanied by showers dur- 

 ing the hottest period of the day, is injurious to 

 the sap as it rises to the more succulent parts of 

 the limbs of the ])ear tree, and to the exposed 

 surface of the bark of the trunk of the cherry 

 and plum tree. On cutting away the unsound 

 parts of the bark of these trees, we see the effect 

 of the want of that healthy action in the sap, the 

 wood is stained by the vitiated state of the color- 

 ing matter, and the disease proceeds unless the 

 whole of the diseased parts be cut away." 



JYew Jersey, August 27, 1829. 



