320 Diseases of Fruit Trees in America. 



the trees have continued healthy. The only efficient remedy 

 that I am advised of, is to cut off and burn the affected parts. 

 All of our stone and many of our seed fruits are grievously 

 injured by insects, which prey upon them in the early stage 

 of their growth, and cause them to drop. Although we can 

 identify the enemy, we are without the means of repelling his 

 attacks. 



We have lost many of our pear trees by what is here 

 termed the blight. The disease is generally first discovered 

 upon the smaller branches, often at a distance from their 

 extremities, by the leaves and bark, at a particular point, 

 becoming black and dead. The foliage and wood above 

 appear fresh and green for some days. At other times, the 

 bark upon the trunk, or at the junction of the main branches, 

 becomes dead in irregular blotches, contracts, and ultimately 

 separates from the wood. In three instances, this season, I 

 have found a circle of bark upon the trunk wholly dead, 

 while all above appeared healthy and vigorous. The seat of 

 the disease seems to be in the cambium, or elaborated sap, 

 which becomes a medium for its extension. The progress of 

 the disease is rapid, in proportion to the vigour of growth in 

 the tree; rich soils and wet seasons being most prejudicial. The 

 evil is confined to no soil or situation, though it is less preva- 

 lent in stiff grounds and grass lands. The apple and quince 

 appear to be generally though less seriously affected. Some 

 pretend to trace the evil to an insect, the Scolytus pyri ; yet 

 my observations have tended rather to multiply than to dis- 

 sipate the doubts which I have had as to the cause of the 

 malady. 



The gooseberry and the grape, particularly the foreign 

 varieties of the latter, are very liable to be destroyed by mil- 

 dew, when partially grown ; and three fifths of these crops 

 are thus usually lost. 



A subscription is circulating among us to raise 2000 dollars, 

 to be awarded as a premium for the discovery of a preventive 

 of the depredations of insects upon our stone fruit. Any 

 thing you can offer, therefore, upon the subject of the preced- 

 ing remarks, will be particularly interesting to your American 

 readers, of whom there are many, and the number is likely to 

 increase as we advance in horticultural improvement. Your 

 publications are much sought after, and highly valued. The 

 Society of this place, of which I am president, subscribes to 

 your Magazine. We have in this state six horticultural 

 societies. The subjects of education and rural improvement 

 are the popular topics of the day. We have a respectable 

 Lyceum in this city, which has published a volume of Trans- 



