December 31, 1898. 



GARDENERS' MAGAZINE. 



867 



T 



Pear m 



Journal 



Agriculture, been very serious this year in 



ore common than is 



various places, reducing the crop of pears, which was already short on account of 

 the unfavourable weather at the time of the " setting 5 ' of the fruit. Some pear 

 growers seeing the young pears falling fast in June, when they are about the size 

 of marbles, think that this drop is due to an unhealthy condition of the tree, or 

 to influences of weather, but it is more often due to the insidious and dangerous 

 action of the tiny pear midge, the presence ot which is far r 

 usually believed. But this mischievous insect is becoming more generally known, 

 and there have never been so many complaints concerning it in any previous 

 season. In most instances the cause of the disorder was recognised, and remedies 

 and modes of prevention only were asked for. In a few cases, where all the 

 larvae had left the pears, and there were no indications of insect attack, inquiries 

 were made as to the source of the injury. 



An experienced and successful cultivator of pears, whose crops had been regu- 

 larly destroyed by this midge, wrote that he feared it would be quite impossible 

 to grow pears in his neighbourhood unless some cure were found. He added that 

 his crop of the pear known as Beurre de l'Assomption was only two pears, 

 although there was a splendid 11 set," and that in the previous year there was no 

 fruit at all on these trees. Another grower said that he had seventy bush pear 

 trees on quince stocks, and had picked off 2,000 infested pears from them ; he 

 had standards close by with infested fruit, but he could not hand-pick these. The 

 infested trees were mainly of the sort named Williams' Bon Chr6tien. 



It would appear that early pears, and those that blossom early, are most liable 

 to this infestation. Williams' Bon Chretien is notoriously subject to it, and in 

 America, where the pear midge is very prevalent and most destructive, the 

 Bartlett pear (identical with Williams' Bon Chretien) is chiefly attacked. 

 Beurre de l'Assomption, earlier than Williams' Bon Chretien, is also frequently 

 seriously affected. Pitmaston Duchess, Marie Louise, Jargonelle, Souvenir du 

 Congres, all early, and like the Bon Chretien in many respects, are also especially 

 liable to be infested. Infestation has been noticed on later pears, as Josephine de 

 Malines and Catillac, but in a much less degree than on earlier varieties. Only 

 forty yards distant from the pear orchard last alluded to was another containing 

 sixty trees of Durondeau and sixty of Louise Bonne of Jersey, which were quite 

 free from the attack. Louise Bonne of Jersey, although fairly early, is not quite 

 so early as Williams 1 Bon Chretien. 



In America the Bartlett and the Lawrence are the varieties most commonly 

 attacked, and it is said that in some districts there has lately been a loss of almost 

 all the Lawrence pears, and a large proportion of the Bartletts, the attacks being 

 so serious and frequent that growers in these localities speak of abandoning pear 

 culture altogether. Professor Riley, writing in 1885, considered that the insect 

 had been imported from Europe, as until it was ifound in 1880, upon a certain 

 farm near Meriden, in Connecticut, no insect of similar habits was known in the 

 United States. 



There is no doubt that it is the same insect as that termed Ctcidomyia nigra 

 by Meigen. This is affirmed by Schmidberger, who first described the habits of 

 this insect in 1831. He says : "The species of gall-midges found by me in the 

 pears are evidently the Cecidomyia nigra % because the description which Meigen 

 gives of the black gall-midge completely agrees with this. I retain Meigen s 

 name, and call it the black gall- midge." Riley, however, suggested that the 

 name of Diplosis pyrivora would be more suitable, and this has been adopted by 

 dipterists. It is not known how long it has been at work in this country. It was 

 first mentioned twenty-five years ago, and there is every reason to believe that it 

 had been present here long before this, for its action upon pears, as pointed out 

 above, closely resembles that of weather and other natural causes, and might 

 easily have been mistaken for these, especially as there were then comparatively 

 few trained observers. 



Life History. 



The fly is nearly one-tenth of an inch long, with an expanse of wings equal to 

 close upon one-fifth of an inch. Its slender body is dark grey, approaching black, 

 in colour; its antennae, with twenty-six joints in the male, are brown and very 

 long ; its legs are also very long, and yellowish brown. The female is slightly 

 longer than the male, having antennae with fourteen joints, and an exceedingly 

 long ovipositor for the purpose of depositing her eggs in the calyces of the 

 blossoms of the pears. Schmidberger witnessed the process of egg-laying, and 

 describes it as follows : " I found the first gall-midge in the act of laying its eggs 

 in the blossom ; this was on April 12. It had fixed itself almost perpendicularly 

 in the middle of a single blossom, and having pierced the petal with its long 

 ovipositor, it laid its eggs on the anther of the still closed blossom. This female 

 was about seven and a-half minutes laying her eggs. When she had flown away, 

 I cut the pierced bud in two, and found the eggs lying in a heap one upon 

 another on the anthers. They were white, longish, pointed on one side, and 

 transparent, and from ten to twelve in number. I afterwards found several 

 midges engaged in laying their eggs as late as April 18, from which day they 

 ceased to appear in the garden. I also saw a midge on the side of the blossom 

 with its ovipositor inserted in it, so that they do not merely pierce the petals, but 



the calyx also." m % m . 



The number of eggs, according to Schmidberger, vanes from a few to more 



than twenty. They are hatched in a very short time if the weather is warm. 

 Schmidberger found small larva on the fourth day after the deposition of the eggs, 

 which begin to bore into the blossom usually in or near the stem of the calyx. 

 " Before the blossom is expanded they descend to the core, so that they may not 

 be exposed to the sun's rays, which would endanger their existence. They 

 separate at the core, and begin to devour it on all sides. When they have con- 

 sumed the pulp of the small fruit they have attained their full size, and only await 

 for a favourable opportunity to leave their still secure dwelling.' Sometimes 

 they fall from the pears to the ground ; sometimes they fall with the infested pears, 

 from which they emerge and bury themselves in the earth to a depth not ex- 

 ceeding one inch. The larva is endowed with powers of jumping like other 

 species of Diplosis. It can also crawl well, but it has no legs. It is rather more 

 than a twelfth of an inch long. In colour it is whitish yellow, becoming rather 

 darker as it gets older. It has what is known as the « anchor process or 

 " breast bone," which serves as an adjunct to the mouth in biting pulp and 

 tissues, " broadly dilated," as remarked by Professor Riley. This is light brown 

 in colour, bifurcate in shape, and is easily seen with an inch lens It is not 

 known when the pupal state is assumed. It has been ascertained that the larvx 

 remain for some time in larval condition before commencing their cocoons, and 

 that they remain, according to Riley, in the cocoons for some time before being 

 transformed to pup*. The pupa is about one-tenth of an inch long, black above 

 and yellowish brown beneath. 



Methods of Prevention and Remedies. 



It is absolutely certain that the author of this mischief to the pear crop is lying 



just under the pear trees from June until the end of March, and only about an 

 inch below the surface of the ground. It ma) therefore be assumed that 

 thoroughly digging the ground beneath the boughs of the pear tree, making allow- 

 ance for the skipping or jumping habits of the larvae as they come from the pears, 

 will bury the larvae so that the ilies cannot emerge. This should be done as a 

 means of prevention where possible. It would be necessary to dig the ground 

 with digging " spuds" so as to completely turn it over, and the action of winter 

 rains and frosts would pulverise it and make it compact, and thus prevent the 

 flies getting through the clods. Obviously this could not be done in grass orchards. 

 Dr. J. B. Smith, who has closely investigated this subject, says " ploughing an 

 orchard " (and ploughing is a frequent mode of cultivating orchards in America) 

 11 infested by the midge, after the middle of June, or, in fact, at any time during 

 the summer, so as to turn the soil at leatt four inches, will probably result in 

 burying beyond resurrection a great proportion of the midges. '* Ploughing 

 is not adopted in England, but many orchards are dug, and in 

 gardens it would be easy to adopt this practice. Dr. Smith, who 

 has made careful experiments in connection with the pear midge, has 

 also found that dressings of kainit immediately under infested trees have 

 been most effectual in killing the larvae. He recommends that the ground under 

 the trees should be top-dressed with one ton of kainit per acre, and mentions an 

 instance of an orchard thus treated, of which the fruit practically escaped infesta- 

 tion, while in an adjoining orchard not treated he failed to find a single fruit that 

 was not infested with lame. This treatment has been successfully adopted by 

 several pear growers. The kainit should be put on between the middle and end 

 of June, before or immediately after rain. It is also suggested that ploughing or 

 digging might advantageously follow towards the end of July or in August. 

 Where pear trees are in grass orchards the grass should be cut very close before 

 the kainit is put on. It is desirable to apply the kainit before the larvae get into 

 cocoons, as it has much more effect upon them in their naked state. Rain, or the 

 moisture of the atmosphere, causes the kainit to dissolve slowly and the caustic 

 solution thus formed burns the tender bodies of the larvae that are within its 

 influence. 



With respect to actual remedies it must be said that they are few and not satis- 

 factory. Spraying with insecticides is of no avail. Spraying with offensive 

 materials, as paraffin or carbolic acid, might prevent egg laying if done just at the 

 right moment. Dr. Lintner suggests sacrificing the Lawrence pear crop by spray- 

 ing Lawrence trees with London purple just after the fruit is formed in order to 

 kill midges and starve the larvae within them. But, unfortunately, other pear 

 trees are liable to infestation, and in England it would be more difficult to select 

 the trees most subject to this attack for this purpose. Picking off and burning 

 infested fruit can be adopted in the case of small bush, espalier, wall trees, and 

 even half-standards ; but it could not be done on standards. As a rule, infested 

 pears can be recognised by their malformation, so that it would be easy, after 

 the pickers were instructed, to pick them off* and leave the sound pears. 



Do Chrysanthemums Wear Out 



It would not be to the advancement of 1 chrysanthemum culture to let the opinion 

 pass that, after all, the continuous demand for new varieties may have its origin 

 in a frivolous desire to be in the fashion. The fact of good, new varieties being 

 in the market would not justify cultivators in changing old for new. Practical 

 growers have not usually done so with other popular flowers, unless under pressure 

 of some new and increasing demand, and this would hardly apply in the case of 

 chrysanthemums, for it is not the decorative so much as the large show varieties 

 that are in question. Experience has taught us that to keep anything like an 

 up-to-date exhibition collection we must discard old favourites, and fill their places 

 with new ; this is necessary as a set-off against the continuous strain made on the 

 large- flowering varieties, for these giants are more or less freaks brought about by 

 high culture and artificial treatment, and so cannot be expected to reproduce their 

 abnormally gigantic proportions for any great length of time. There are no 

 exemptions from this wearing out amongst the large-bloomed varieties in all the 

 different classes. Of course, the Japanese have their ranks filled up much better 

 than the others, yet even among these (from the exhibitor's point of view) we 

 have no coloured ones to surpass for size of bloom The Sultan, Comtesse de Beau- 

 regard, Baron de Prailly, Triomphe de la Rue des Chatalet, Meg Merrilies, Ralph 

 Brocklebank, Carew Underwood, Margaret Marrouch, Houle d'Or, and Madame 



C. Audiguier of ten years ago. 



The incurved varieties were in their hey-day six or eight years ago, but since 

 then we have seen Prince Alfred, Lord Wolseley, M. Bahuant, John Salter, Mrs. 

 R. King, Nil Desperandum, and many others go down. The Queen family that 

 bowled out Jardin des Plants, The Beverleys, Mr. Bunn, Geo. Glenny, Mrs. 

 Dixon, Mr. Gladstone, Mrs. Halliburton, &c. f are in their turn giving way. Then 

 in the Japanese anemone class we have had to pirt with Madame Cabrol, Fabian 

 de Madanarey, Sceur Dorothi Soeull, and many others. Cramming and crowding 

 may hasten decline, and most growers have their plants too crowded in November; 

 yet I believe that even if we gave up rank culture and ceased the introduction of 

 new sorts we should have few very large bloomers in eight or ten years' time. 

 Consequently we must continue to welcome new varieties from every quarter, 

 for there will be no relaxation of the high culture or the production of more vital 



force than the flower needs. 



Nor 



A. Fin ml. 



Crimson Chrysanthemums.— After seeing the novelties of the past two 



or three seasons, but particularly those of 1 898, I cannot help wondering how 

 many of the present-day cultivators there are who can recall to mind the varieties 

 we used to call crimson nearly.twenty years ago. In the incurves there are absolutely 

 nothing worth the name of a crimson. Among rcflexed we had King of the 

 Crimsons, the old but very small Julie lagravcre, a little later Cullingfoidi, and 

 in the Japanese but a very few that could be considered of that colour ; but now 

 how brilliant are some of the crimsons, thanks to the unceasing efforts of the 

 raisers. Mr. W. Seward's name certainly deserves a special mention in con- 

 nection with this colour, for his acquisitions are beyond question some of the best* 

 The very dazzling crimson H. J. Jones shown at one of the latest meetings of the 

 N.C.S. Floral Committee has outdistanced every other novelty of that shade, 

 which will make it a welcome addition not only on the show-board but also in 

 groups for decoration. Very fine, too, in their various tones of this once much- 

 needed colour are Joseph Chamberlain, Owen's Memorial, Lord Cromer, Royal 

 Standard, Master H. Tucker, all Japanese, and Emile Noninof the old incurved 

 type. Apart from these there are many others closely bordering on the crimson, 

 but which are properly described as reddish- bronze and warm golden terra- cotta 

 colours, that have been also greatly improved and intensified by the raisers, both 

 at hnme and abroad, during the past few years.— C. II. P. 



