478 DISEASES AXD INSECTS. 



■with Lake Ontario, fine crops are produced with compara- 

 tively little difficulty from inildew or rust. This would 

 indicate as a remedy, a cool soil and situation, and mulch- 

 ing the roots to keep them cool. The trees should be 

 renewed every three or four years, and they should be kept 

 vigorous by liberal manuring and good culture. 



Hot and Mildeio of the Grape. — Both the rot and mil- 

 dew on the grape have been attributed to various causes, 

 none of which seems to prove reliable. Both diseases 

 seem to come and go with seasons, now liere and there 

 excessive upon one variety one season, and another the 

 next, evidently to us bearing the impress that it is 

 miasmatic or sporadic, and developed according to the 

 atmospherf^ and Condition of the vine as regards health 

 and vigor. The preventive seems to be in the free use 

 of sulphur, by dusting the vines and keeping the influence 

 of the sulphur thereon, from the time the seed is 

 formed unt^l the coloring is at least half-completed. 



The Plum-tree Wart or Black-Knot. — The cause of this 

 disease is still a matter of doubt and uncertainty. Some 

 hold to tlie opinion that it is a gall produced by an insect, 

 others that it is of fungous origin. The latter opinion is 

 entitled to the greatest weight. We do not believe that 

 insects have any agency whatever in producing this dis. 

 ease. Cions should never be taken from a diseased tree. 



Cutting out the diseased branch clean to the sound 

 wood, the moment the knots begin to appear, is an 

 effectual remedy, and they should all be burnt up. We 

 have saved trees six inches in diameter, that were af- 

 fected on the trunk so seriously, that one third of its 

 thickness had to be removed to get below the disease. 

 After it -Was cut out, we applied a plaster of grafting 

 composition, covered it with a cloth, and in two years 

 it was all Sealed over and sound. 



Plum-tr^^s are so neglected in the country, that mul- 

 titudes. -^ *hem are now standing literally loaded with 



