Ai>BiL 2, 1008. 



The Weekly Morists' Kcview, 



HYBHIDIZATION OF HOSES. 



[A paper written by Alex Dickson, of Alex 

 Uickson & Sons. Newtowuards, Ireland, and read 

 t>efore the American Rose Society in Chicago, 

 March 27, 1908.1 



It was with considerable hesitation 

 that I consented, at the request of jour 

 societj, to write a paper upon hybridi- 

 zation and cross-pollination in relation to 

 the rose. I may say at once, it is a re- 

 quest that I have refused many times 

 from similar organizations here and else- 

 where, because I have always felt, and 

 indeed still feel, it is a subject upon 

 which it is extremely diflScult to write 

 a satisfactory paper. The subject is 

 one which cannot possibly be dealt with 

 satisfactorily in a paper such as the 

 present, and the chief difficulty one has 

 is selecting the lines upon which to 

 write, or the point of view from which 

 to discuss it. I will do my best to 

 make the paper as interesting and in- 

 structive as I can within the limited 

 scope at my disposal. I have given the 

 subject my most careful consideration, 

 and I am convinced that the best method 

 of dealing with the subject in this 

 paper is to give you, in a condensed 

 form, some of the results which have ac- 

 crued from the labors of my brother and 

 myself, extending over a period of al- 

 most thirty years. 



From a Practical Point of View. 



I would ask those who hear this paper 

 read, and those who may read it for 

 themselves, to remember that it is written 

 by a professional rose grower, and, there- 

 fore, by one to whom the practical re- 

 sults, ■ from a commercial standpoint, 

 were of the most vital importance, and of 

 necessity this point of view had always 

 to be borne in mind by my brother and 

 myself in our line of experimental in- 

 quiry; and it is from this point of view 

 that I deal with it. 



Hybridization is a subject of intense 

 interest, and the practical application of 

 the science opens up an infinite and 

 even inexhaustible field of inquiry, but 

 those of us who are professionally en- 

 gaged upon this branch of horticulture 

 must abandon, to some extent at least, 

 the scientific aspect, in favor of the 

 practical. With the stern realities of 

 life facing me, I have many times, con- 

 trary to my desire, been compelled to 

 abandon scientific lines of inquiry, as 

 against the production of new varieties 

 of commercial value — a situation I re- 

 gretted, but could not help. 



After thirty years' steady and con- 

 tinuous work I am inclined to the opin- 

 ion that the further one pursues the 



subject of hybridization, the greater the 

 field for exploration. I have often 

 thought, while pursuing my work and 

 watching the results, that the effect was 

 much like that produced when climbing 

 up a steep mountain — the farther one 

 rises the more the plains below are open- 

 ed up. I will try to explain more fully 

 as I go on exactly what I mean, and 

 the foregoing observations are 'made 

 with a view to render less keen the 

 disappointment which I feel will inevi; 

 tably follow the reading of this paper. 



Much Due to Chance. . 



I am conscious that my observations 

 will be read before, and by, men of 

 practical experience in horticulture, and 

 particularly in the culture or advance- 

 ment of the rose, and by men keenly in- 

 tent upon the development and improve- 

 ment of the rose; and I am sorry, for 

 this reason, that I can give little prac- 

 tical assistance to any who are . desirous 

 of entering the field of hybridization on 

 their own account. I may, however, ren- 

 der their disappointment less acute. The 

 main reason why I can render little prac- 

 tical help is that, when all is said and 

 done, hybridization is a science of pure 

 experiment, or rather chance, as I can 

 easily show. To do this it is only nec- 

 essary for me to assume that every one 

 — at least every one interested in horti- 

 culture — knows that, so far as seed-bear- 

 ing plants are concerned, they will re- 

 produce their species in some shape or 

 form, perhaps with some variation, or 

 perhaps exactly similar. And it follows 

 that by the fertilization of different va- 

 rieties of thft same species, new varieties, 

 or, at least, varieties with some distinct- 

 ive feature, may be produced. It is a 

 different matter, however, to reduce the 

 chaos, which results from indiscriminate 

 cross-fertilization, to something like defi- 

 nite order — a result far beyond my am- 

 bition or the scope of this paper, if in- 

 deed it is at all possible. All I can do 

 in this direction, and indeed it is very 

 little, is to give some results of our 

 labors in hybridization. 



Early Discouragements. 



We began work in 1879, and naturally 

 our first operations were upon what were 

 considered the finest show varieties of 

 that day. Naturally, we chose parents 

 of the choicest colors, having beauty 

 of form and. as far as possible, vigor 

 of habit. Tne hope, of course, was that 

 the fertilization would reproduce vari- 

 eties of a different kind, with at least 

 some of the qualities for which the 

 parents had been selected. The results 

 for many years were disastrous. 



Keen and bitter disappointment fol- 

 lowed our experiments. We, however, 

 persevered, always upon fixed lines, care- 

 fully recording our crosses and results, 

 making a close and careful observation 



of*the jnoBt important features of the 

 offspring of the cross; and I regret to 

 say that in the majority of instances 

 there was nothing but dismal failure to 

 record. I think I can safely say that 

 the most certain result of our crosses in 

 the early stages of our experiments was 

 to convince us of the absolute uncer- 

 tainty of what our results would be. 



This prevails even now, though in a 

 lesser degree. Possibly this is one rea- 

 son why rose hybridization is so intensely 

 interesting. There is always and ever 

 the element of uncertainty iti it, so 

 dear to human nature. One never knows 

 what the fertilization of any two va- 

 rieties will produce, or more correctly, 

 how many different varieties. One seed 

 pod containing four seeds may produce 

 — and has produced, to my knowledge — 

 four seedlings absolutely distinct in every 

 conceivable respect. Many and many a 

 time I have seen produced from the 

 seeds sown from one hip half a dozen 

 seedlings, absolutely distinct in color and 

 form, some as single as the -ordinary 

 dog rose, and some so full in substance 

 that it was impossible to get them to 

 open even under glass. 



A Change of Method. 



In the early eighties, when we began 

 to see the results of our labors, we 

 abandoned the original basis of our ex- 

 periments, namely, the fertilization of 

 the better varieties of hybrid remontant 

 or perpetual, and began a series of cross- 

 pollination between the hybrid perpetual 

 and teas and Austrian briars, and then 

 using the results of this first cross in 

 a systematic course of inbreeding. The 

 main object which we had in view was 

 to produce varieties of roses at once 

 vigorous in their habit and continuous 

 in their bloom, at the same time re- 

 taining the absolute essentials of all 

 good roses; namely, beauty of color, per- 

 fection of form and delicacy of per- 

 fume. It was, of course, a great am- 

 bition, and how we have succeeded we 

 must leave the world to judge. Broadly, 

 I would say that such success as has 

 attended our labors is due far more to 

 the careful selection than to any defined 

 plan of fertilization. 



As a broad basis of our experiments, 

 Ve took as parents such varieties as 

 appeared to us to embody the chief ele- 

 ments of our ideal, and worked steadily 

 from these. W^e had, of course, to ex- 

 periment upon a very extensive scale, 

 and my point will be readily appreciated 

 when I say that we were only able to 

 retain for use, either for further fertili- 

 zation or for commerce, about five per 

 cent of the seedlings raised. 



To appreciate the labor this entails 

 upon the hybridizer, one must follow the 

 rose from the hip until it reaches ma- 

 turity. In hybridization, carried out 

 upon a systematic plan such as ours, it 

 means that the plants with which we 

 are working have to be specially selected, 

 planted and grown, and the blooms fer- 

 tilized. There is then the period re- 

 quired to ripen the hip, and in Ireland 

 this takes considerable time, owing to 

 the cold and dampness of our climate. 

 Then comes the sowing of the seed, and 

 the attention and care during the period 

 of germination. 



In this respect it is interesting to 

 note the wide differences in the period 

 of germination in the different cases. 

 In some instances the seed will germinate 



