14 



to retard growth, prevent thorougli maturing of tlie plant, and thus weaken and 

 destroy its ability to resist rigorous temperatures. 



The second form of mildew is that which attacks most varieties of our native 

 gi'apes. This invariably commences on the underside of the leaves ; its first 

 appearance is that of a Avhite downy spot, spreading rapidly under conditions 

 favorable to its growth. A practised eye can readily detect affected plants from 

 the yellowish spotted appearance presented on the upper surface of the foliage. 

 As it continues to develop, the vitality of that portion of the leaf is destroyed, 

 and becomes of a brown color, under the influence of the sun.' This brown, 

 burnt, or scalded appearance, so frequent on vine leaves, is, therefore, the result 

 of mildew, although many grape-growers do not i-ecognize it as such. 



When this destruction of foliage reaches a certain point the young shoots 

 remain green, and the wood never ripens. The fruit will also ripen imper- 

 fectly, if at all, and many of the berries remain green on the bunches — an ap- 

 pearance by no means rare in the Isabella and other well knoAvn kinds. 



It is conjectured that the rot in the berry is a disease distinct from either of 

 those mentioned above. On this matter there are various opinions held by our 

 coiTcspondents. One writer remarks that, " although the leaf mildeAv may fre- 

 quently occur without rot in the berry, yet the rot is always accompanied with 

 mildewed leaves." Again : it is evident, from the returns sent us, that the nature 

 of tbe soil has a decided iufluence ; on well drained, or on gravelly and sandy 

 soils the rot is seldom seriously injurious. " My soil," writes one, " is gravelly 

 sand, with, perhaps, not more than two per cent, of organic matter. I have no 

 trouble with rot or mildew ; I am well sheltered on the north and west, and 

 both Catawba and Isabella bear abundantly and ripen in perfection." On the 

 other hand, it would appear that vines on clayey or strong loamy soils Avere 

 annually, more or less, subject to this malady. We learn of a vineyard of the 

 Catawba which is to be rooted up on account of losses from rot. Much can be 

 gleaned from casual remarks. A letter before us mentions a case of rot occur- 

 ring in the Delaware grape, Avhere the vines were highly manured. It is gen- 

 erally allowed that of all cultivated varieties the DelaAvare is, perhaps, the 

 most exempt from the rot. The Concord, heretofore considered proof against 

 all diseases, has suffered severely from rot in many localities. A Avriter from 

 northern Pennsylvania remarks that, " in our mountain ranges we are not 

 troubled Avith grape rot." Another, from an eastern county of the same State, 

 informs us that " all my grapes haA^e rotted, more or less, this summer, except 

 the DelaAA^are and MaxataAAuy." He does not mention Avhat other A'arieties he 

 cultiA'ates, AA'hich it is important to knoAv. 



These extracts from the correspondence of the Department are introduced for 

 the purpose of pointing more definitely to the most important objects of atten- 

 tion in further obserA'ations. 



INJURIOUS INSECTS. 



During the course of the last month numerous insects have been sent to this 

 office for examination; many of them being of little consequence to the farmer, 

 we Avill merely mention some which require the attention of the agriculturist at 

 the present time, or such as not yet being widely disseminated, if not made 

 knoAvn in time, may eventually prove very injurious. Every farmer must ha\'e 

 observed his apple, cherry, and various other trees, covered Avith a AAeb Avhich 

 forms the nest or shelter for hundreds of small hairy caterpillars. These should 

 now be taken from the trees and the caterpillars either crushed under foot or 

 burnt; as, if allowed to perfect their changes and become moths or millers, next 

 year we may expect our orchards and shade trees to be almost entirely de- 

 foliated. This insect can be destroyed most readily AA'ben in the larva or cater- 

 pillar state, congregated together in their web, and before they have changed 



