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Worcester; Mr. George Bunyard, Maidstone; and Mr. Lewis Killick, Maidstone; the Rev. C. H. Bulmer, Credenhill Rectory, Hereford; and Mr. G. H. Piper, Ledbury, only taking the cider and perry fruit division.-The Herefordshire Incumbent.

I am anxious to add a postscript to my report of above Exhibition in reference to the Onibury Pippin. This excellent dessert Apple cannot be too widely made known and recommended; indeed, I believe it to be worthy a place in every collection however small, where it might form a well-matched triplet with one of the very best and hardiest culinary Apples, Wormsley Pippin, and that wellknown late dessert Pear, the Monarch; all chef d'œuvres of that indefatigable pomologist, Andrew Knight. It was a subject of general regret that a choice cellection of cider Apples (some fifty varieties), expressly sent from Normandy to the Exhibition at Hereford, arrived too late. From a cursory glance I have had there is hardly any resemblance to be now traced between them and our present Norman cider varieties, presumed to have been introduced from Normandy into our Herefordshire orchards by Lord Scudamore, of Holme Lacy, about the early part of the seventeenth century. I will only mention that the nomenclature of the several varieties, as now grown in the different countries, is as widely different as their structural and other characteristics; but this is not the occasion to more than allude to this interesting subject. -The Herefordshire Incumbent.

CANKER IN APPLE TREES.

THERE are probably several diseased conditions of Apple trees known as canker. During the past two or three months I have been looking into this disease somewhat attentively, and I have come to the conclusion that the commonest and most serious form is due, as was pointed out by Goethe, to a sphæriaceous fungus, Nectria ditissima (Tul.)* The various members of Sphæriacei occur, as a rule, upon dead wood-not upon the living tissues of plants. There are, however, many important exceptions-such, for example, as the Valsa parmularia, described many years ago by Mr. Berkeley, upon living Oak twigs. More important, from an economic point of view, is the Sphæria morbosa of Schweinitz, the cause of black knot in Cherry and Plum trees in the United States: closely allied to which is Gibbera vaccinii upon living branches of Vaccinium Vitis-Idea in our own country. The Dothideacea, too, occur, many of them, upon living leaves and branches, as the genus Phyllachora for example. Although there is nothing impossible in the notion that a Nectria may be parasitic upon living branches, yet I must confess my first impression was, that the fungus found a suitable home upon Apple twigs which were already dead rather than that it was the cause of the death of the affected branches. It is well known that winter and spring are the seasons in which the Sphæriacei as a rule are found in the best condition of fructification. I have, therefore, closely examined cankered Apple trees during the past two months wherever I have had an opportunity of doing so, and in no single instance have I failed to find the Nectria upon every tree examined. It is not implied that every cankered patch was found producing perithecia; at the same time the majority of the cankers upon each tree were found bearing the fungus in abundance: and, further, it was not found upon any other part of the trees. The trees were not confined to one garden nor to one locality. The specimens which I submitted to the Scientific Committee recently were gathered from (1) Mr. J. Bird's nursery at Downham; (2) Mr. S. N. Marshall's garden at West Lynn; (3) Mr. J. T. Stevenson's garden at Clenchwarton; (4) Mr. C. Peek's orchard at Tilney St. Lawrence; (5) Mr. G. B. ffolke's garden at Wolferton; and (6) Mr. T. Pung's garden at King's Lynn. When the parasite gains an entry into the bark of a medium-sized branch, which it often does through a lateral twig having been broken or cut (fig 1), it at first causes the death of the bark and subjacent wood to only a limited extent. The bark cracks concentrically; in the cracks and upon their edges the perithecia are most commonly found. It is obvious that a certain time must elapse between the period of infection and the time at which the mycelium or spawn can develope its perfect fruit. This probably takes some months, for it will be seen by inspecting the specimens them

*Nectria dittissima. Tul., Carp., iii., p. 73, t. 13, f.1 -4 (= N. coccinea of many authors).— Perithecia widely scattered or densely gregarious, globoso-obtuse then papillate, naked blood red asci cylindrico-clavate, 82 × 8 mk.; sporidia ovate-oblong, uniseptate, 14 X6-8 mk., hyaline.— Conidia Tubercularia crassostipitata Fuckel, Symb. Mycol., p. 180., ovate-oblong, continuous, 6-8 × 3-4 mk.

selves that the perithecia are most abundant in those cases in which this devitalised area has become surrounded by an enlarged and swollen margin (fig. 2, A, B) of healthy bark. When the parasite attacks a small branch shoot of the last year it kills it outright for some inch or two downwards; especially is this the case when the end of the shoot has been cut off (fig 2, B); but with the older and thicker branches attacked lower down the disease gradually but surely works its way through the branch, eventually cutting it quite through (fig 2, A). In this case a callus above and below, as well as surrounding the canker generally, is observable. Thus the distal part of the branch becomes in course of time strangled by the fungus. It is useless to look for perithecia on those places in which the disease has only just made its appearance. As far as I can judge, the cankers made last autumn produce the perfect fungus in spring.

In the Gardener's Chronicle, March 8, 1884, p. 312, Goethe's paper in the Monatschrift des Deutsche Garten for 1880 is referred to, in which the author has shown that Nectria ditissima is capable of producing the disease on Apple, Beech, and Sycamore respectively. The remedy is to cut out the diseased parts and to seal the wounds thus made, which would otherwise remain as vulnerable points inviting the attack of the fungus-spores, by painting them over with warm coaltar.

The injuries which branches receive by rubbing against one another may, of course, open the door to the fungus spores; but unless the latter be present, a true canker is not produced by this means.

At a recent meeting of the Scientific Committee a very curious form of canker on Hawthorn was exhibited, in which the disease resembled a honeycomb. Whether this was due to an insect or to another fungus, I cannot at present certainly say. It, however, bears some resemblance to the cicatrix of a wound caused by a fungus, Rœstelia lacerata, attacking a young twig last summer, and the presence of some brownish spores in the bottom of some of the cells seems to favour this view. There were also, however, found some spores very like those of a Fusisporium. By further observation I hope to clear this up*-Charles B. Plowright, King's Lynn, April 7th. (The Gardeners' Chronicle, April 19th, 1884.)

*This_subsequently was found to be caused by the Ecidiospores of Gymnosporangium Confusum, Plow.

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