J 046 



The Weekly Florists' Review. 



introduction of infested i)Iants. Fi-om 

 the fact that there are but few larva; 

 present up to tlie month of Jlay, but that 

 they increase in number during tlie sum- 

 mer and altogether disappear in late Oc- 

 tober, it would seem that they follow 

 very closely the habits of the British 

 species, Dichelomyia rosarum. 



The eggs are deposited either in the 

 unfolding leaf buds or under the sepals 

 of tlie blossom buds, the latter position 

 seemingly being preferred by the females 

 where there is an opportunity for selec- 

 tion. In case the former is chosen, the 

 eggs are deftly inserted in the condupli- 

 cated leaves between what would, later 

 on, constitute the upper surfaces of the 

 two halves of the unfolded leaf. The 

 maggots appear to fasten the edges to- 

 jjether with some viscous matter, thus 

 forming a sort of pod within which they 

 attain their larval growth. If there arc 

 few larv;e, their effect is to cause more 

 or less prominent swellings on what 

 would later become the lower surface of 

 the leaf: if there are many larvae in the 

 leaf, it simply becomes distorted and 

 •discolored and dies. In case of blossom 

 buds, the effort of the female seems to 

 be to place her eggs as far under and 

 near the base of the sepal as possible, 

 but there does not appear to be any regu- 

 larity either in their exact position "or 

 numbers. Occasionally they will be 

 found stuck in the sutures separating the 

 sepals. The ovipositor of the female is 

 capable of great cvtension, and I have 

 observed it to be curved, coiled, and 

 twisted in her efforts to push it under 

 the closely adhering sepal of a verv 

 young bud. Frequently, after this has 

 been accomplished she is unable to extri- 

 cate it, and dies attached to the bud. In 

 one case I found two females on a single 

 bud, they having apparently perished in 

 this manner. Nevertheless! the females 

 seem to be strikingly attached to their 

 labor of ovipositing, as, in a propagatim; 

 house where there were thousands of 

 young plants with but few blossom buds, 

 if they were driven from one of these 

 they would fly but a few inches away and 

 soon return. They are exceedingly min- 

 ute, and obscure while on the wing, hav- 

 ing much the appearance of floating par 

 tides of dust. 



While the larva; are at first usuallv 

 well covered by the sepals and folded 

 leaves, if excessively abundant they will, 

 later swarm out and over the outer sur- 

 face, especially of the blossom buds. 



In England and Europe there is also 

 a rose-attacking insect which can only 

 be separated anatomically from our 

 species by the number of aiitennal joints, 

 a character known to be somewhat vari- 

 able. Tlie habits of the two are verv 

 much alike, except that in Britain the 

 larva> affect the leaf buds and not the 

 blossom buds, both in the rose houses 

 and in the open air. Our species attacks 

 roses only in rose houses, largely eonfinim; 

 its ravages to the blossom buds, but when 

 attacking the leaf buds affects them as 

 does the English species. In Britain, 

 and in the open air, the wild, or dogrosc, 

 though it grows rapidly, cannot eertainlv 

 make as rapid growth as dees the Meteor 

 in our rose houses, where all the ingen\i- 

 itv of the grower is centered on produc- 

 ing the most rapid and vigorous growth 

 possible. It is doubtful if the American 

 species could, under these sonditions, de- 

 velop in any considerable numbers in 

 the leaf buds, as the growth of the buds 

 is so accelerated bv artifi^'ial conditions 



tiiat there is not time for the larvae to 

 develop within tlicm before they become 

 too much expanded and too lough to ad- 

 mit of the larva; affecting them. The 

 blossom bud, being of a slower develop- 

 ment, affords a longer time for the larvtc 

 to mature, and, besides, presents food of 

 a different character from that of a leai' 

 bud. 



To sum up the whole discussion, then, 

 it is not now possible to regard our 

 -American species as the same as that 

 occurring in England and Europe, known 

 as Dicliclomyia rosarum Hardy, but that 

 it is closely allied to that species can 

 not be doubted. We must wait for fu- 

 ture studies to show us whether our 

 .\niericanized form has sufficiently de- 

 veloped to admit of its being separated 

 as a new genus and species. 



DAHLIA PROPAGATION. 



If this subjci-t is not already talked 

 to death it seems to me it will be 

 shortly, but as I think I must have been 

 the innocent cause of all this discussion, 

 perhaps a few words are due the public 

 from me, and at the same time I wish to 

 express my appreciation to the publish- 

 ers who have so kindly given space to 

 this question. 



What is it all over, anyway? Simply 

 that I have presumed, without asking 

 permission, to issue a trade catalogue in 

 which I illustrate the comparative sizes 

 of dahlia tubers. A reproduction of the 

 illustration appears herewith. The fol- 

 lovving is the paragraph relating to the 

 illustration : 



-V glance at the illustration will show how de- 

 ceptive the words "field clump" or ."whole 

 root" may be. Some growers propagate from 

 eiittiugs and some from tubers. Each produces 

 what is known commercially as "clumps." It 

 is therefore of the greatest importance to the 

 purchaser which kind of a clump the adver- 

 tisemeut or quotation refers to. Fig. 2 or Fig. 

 The figures presented represent fairly the 

 relative sizes of commercial dahlia tubers as 

 grown in this country. 



As explained in my catalogue, the sizes 

 are comparative and not fixed weights. 

 The variety I used for the illustration 

 was Countess of Lonsdale, which every 

 grower knows is only a medium-sized 

 root, as seen in Fig.' 3. Had I used 

 Earl of Pembroke, Gloriosa, or some 

 other large-rooted variety, Fig. 3 would 

 probably be marked from five to seven 

 pounds and the other figures would be 

 coiTespondingly larger. 



With one exception all the writers who 

 have expressed themselves are practically 

 agreed as touching the uniform quality 

 of stock grown from tubers and stock 

 grown from cuttings, myself among the 

 rest. The one dissenting voice is that 

 of my friend W. P. Peacock, who in the 

 March 24 nimiber of the Review ex- 

 presses his views freely on this "burning 

 (|uestion," as he terms it. His ideas are 

 so widely at variance with recognized 

 authorities that I venture to say that 

 his position upon a number of "points 

 cannot be maintained by the evidence. 

 In my opinion growers will be slow to 

 accept his statement that a rooted cut- 

 ling planted out in May will grow a lar- 

 ger plant, of superior quality and have 

 a larger root by fall than a tuber under 

 the same conditions. Why should it? 



Neither am I convinced that propaga- 

 tion from cuttings is more expensive. I 

 have always believed it to be a far 

 cheaper method. The evidence of this is 

 seen in the fact that all dealers offer 

 green plants at a much lower price than 

 the dry tubers. There are good reasons 

 why this should be so, as a green plant 



can be developed and placed on sale or 

 set m the ground all within a short 

 month, while a tuber must receive room 

 and care for a full year. 



Neither am I at all convinced that 

 there is no danger from over-propagation 

 or late planting. That a dahlia will 

 stand a great deal of propagation is 

 freely admitted, but there is a limit, espe- 

 cially to late propagation, which will 

 give the young plant no time to mature 

 its strength for the next season 's growth. 

 In my judgment many of the weaknesses 

 of the newer varieties are direeth- trace- 

 able to over-propagation. 



That tuber-grown stock is necessarily 

 badly broken in the handling, may or 

 may not be true. If careless help is 

 employed it will be true, but I lose onlj' 

 a very small percentage of roots through 

 breakage. And here let me say that all 

 varieties with ill-formed roots or weak 

 necks should be discarded, as they prove 

 a continual source of annoyance to grow- 

 ers, dealers and amateurs. With the many 

 thousands of varieties to select from there 

 is no need of growing any but well- 

 formed roots and flowers. 



I was particularly impressed by one 

 of Mr. Peacock 's remarks when he said 

 we should get down to a " given 

 variety. ' ' For comparison he has selected 

 Sriemhilde as the subject of his illustra- 

 tion and the major portion of his re- 

 marks. So for the purpose of the argu- 

 ment we will take Kriemhilde. His illus- 

 tration shows three very compact speci- 

 mens not susceptible to division by reason 

 of the interwoven condition of the roots. 

 His contention that these will not break 

 in handling will be admitted. 



The combined weight of these three as 

 shown is six and one-quarter pounds, or a 

 little over two pounds each for the aver- 

 age. In another article reference is made 

 to these same three specimens in the fol- 

 lowing language : ' ' Many other varieties 

 grow much larger and, of course, others 

 grow much smaller. ' ' By this statement 

 are we to understand that these speci- 

 mens are to be considered a fair aver- 

 age for cutting-grown stock? 



This will bring us face to face with a 

 business proposition. Many if not all 

 wholesale dealers in dahlias have two 

 prices, one at which the purchaser pays 

 the expressage and one for small orders 

 at which the dealer prepays the package 

 to any portion of the United States. This 

 additional fee for delivery is from 20 to 

 2.5 cents per dozen. Mr. Peacock has 

 such a notice in his 190-t catalogue. Are 

 we to understand that he will send one 

 dozen tubers of Kriemhilde to a distant 

 city for 2.5 cents? By mail these would 

 of necessity be six packages of four 

 pounds each and $2 worth of stamps 

 would be necessary, not counting any- 

 thing for weight of packing material. 

 This might do with a high-priced variety, 

 but how about those varieties priced at 

 $1 per dozen? 



Does not this verv general and fairly 

 uniform charge of 25 cents a dozen for 

 postal charges go to prove the correctness 

 of my contention when I place the weight 

 of commercial dahlia tubers at from two 

 and a half to five ounces each, which is 

 amply large for all practical purposes 

 and as large as dealers can handle profit- 

 ably in a mail or express trade? 



Is there any need of increasing the size 

 of the tuber? Do not the small pot roots 

 as supplied by the English growers, 

 weighing only one ounce, produce just as 

 fine plants and flowers as the large roots 

 grown for the trade in our country? I 

 remember that when I began as an ama- 



