HORTICULTURAL REPOSITORY. 



2S:t 



circulation is infinitely more rapid in the animal than 

 in the vegetable, th ■ cure in the latter is more easy 

 and certain. Governed by this opinion I have perse- 

 vered in cutting off and burning the diseased branch- 

 es, until I have overcome the evil, although some 

 gardens in the vicinity are as much afflicted as ever. 

 1 have some thousands of the plum and Morello 

 cherry on my grounds, and have found but one dis- 

 eased tree among them during the season, and that 

 came into my possession last spring. Forty years 

 ago the Hessian fly was unknown to us. New ene- 

 mies to our crops are annually recognized in the 

 insect tribes. 



I do not believe this disease is produced by the 

 Sun; because its attacks are indiscriminate, where 

 the sun's rays are obstructed by foliage, as well as 

 where exposed to its rays ; on the north as well as 

 the south ; on horizontal as well as perpendicular 

 •shoots ; and on the under as well as upper side. 



I dissent equally from the theory, that it is occa- 

 sioned by only deleterious mattor in the soil; because 

 it occurs where the soil has undergone no apparent 

 •Change; and because, were this the case, the whole 

 system of sap wood, through which the juices circu- 

 late before they become vegetable food, would be a- 

 IFke affected, and first the roots and trunk. 



I object to every opinion which goes to ascribe it to 



"atmospheric influence ; because this influence would 



exert itself first on the leaves, the most sensitive and 



exposed organs, and the extremities would invariably 



give the first indications, which is not the case. 



I do not believe it peculiar to any particular varie- 

 ty ; becmse it attacks my apples as well as pears. — 

 It most abounds where the wood is most thrifty and 

 tender. My Poir d'Auch, Winter butter and Priest- 

 ly apples have suffered most. 



It ill becomes me, after objecting to other theories, 

 to setup one of my own, without ample proof to sup- 

 port it. But as my only object is to excite investiga- 

 tion, and elicit truth, I hope I shall be pardoned for 

 my presumption in suggesting it, unsupported as it is 

 5y any thing but casual observation and reflection. 



My theory is, that the new disease of the pear and 

 apple trees, like that of the plum and Morello cherry, 

 is occasioned by an insect which injects a matter 

 through the bark, that poisons or vitiates the descend- 

 ing sap, and causes disease and death. And my rea- 

 sons for this opinion are briefly, — 



1. That the progress of the disease is down, with 

 the elaborated or proper sap, towards the trunk and 

 xoot ; and not up, with the ascending sap, towards the 

 extremities and leaves ; that it is perceptible to a 

 •greater extent on the cambium, and inner bark, than 

 on the exterior surface. The former will be found 

 thrown; in longitudinal slips, sometimes an inch low- 

 er titan, the exterior is affected, Xb.fi sap frequently 



continues to ascend, is elaborated, and nourishes an« 

 preserves the verdure at the extremity, after tlr<j 

 branch is affected, and the whole circle of the bar!) 

 below become brown and withered ; and in these CHj 

 ses it is not until the sap-wood under the blightel 

 part is contracted by disease, and refuses to perfoj'.n 

 its office, that the extremity peris-hes. 



2. That the commencement of the disease, frc; 

 what I have stated, is in the descending sap, is com- 

 municated next to the bark, and finally to the wood. 



3. That it is most common in thrifty branches, ten- 

 der bark, and new wood. And 



4. That it appears only when the sap is in full flow, 

 and vegetation luxuriant ; and extends in proportion 

 to the vigor of circulation and growth. 



What ihe insect is that does the mischief I oil! not 

 pretend to determine. I have seen insects, in the 

 morning, so firmly attached to a branch (at the com- 

 mencement of the new growth) of an apple tree, that 

 cutting off the limb did not disturb them ; and at eve- 

 ning I have found many of them enveloped in the 

 dead and curled leaves of a branch which they had 

 probably destroyed in part. As I am no entomolo- 

 gist, I submitted them to a gentleman of science, whp 

 gave them the generic name of saperia, the specific 

 name not being known. J. BUEL, 



Albany, Nov. 7, 1828. 



— -.>8 ©©<••' ! 



[original.] 

 ART. 100. — Ji shirt treatise on Botany. — [Con- 

 tinued from page 188, No. 8.] 



VIII. »F THE CLASS OCTANDRIA. 



One of the prettiest plants of this class, is the Nas- 

 turtium, or the great Indian Cress, Trcpceohun majus, 

 which Linneus named the Trophy plant, from its 

 leaves being shield-like, or peltate, and its flowers re- 

 sembling a helmet. It is a native of South America, 

 but is very commonly cultivated here : ; The Sugar, 

 (Acermccharinwn,) andotherkinds of the Maple, are 

 also found in this country. The cranberry, Oxycoc- 

 cits, with its large scarlet leaves, that are brought in 

 in large quantities to our markets, is an octandrous 

 plant ; so also are the Heaths, (Erica,) a very large 

 genus of plants, principally found at the Cape of 

 Good Hopre, and one or two species in Europe, which 

 abound in uncultivated places. Further examples are 

 the Lace wood, Lagetta lintearia, from the inner bark, 

 of which a kind of net work, similar to lace is 

 produced ; and the Calanckoe, a remarkable plant, 

 native of the Isle of France, having a pinnate-winged 

 leaf — the leaflets are toothed or indented, and from 

 each of their indentures a radicle is put forth, which 

 lakes root and becomes a new plant. 



IX. OF THE CLASS ENNEANDRIA. 



This is a small class. The Camphor tree, Lawns 

 ■ camplwre, and the Glonarnon tree. Lawv.s cintiaw^ 



