July 19, 1913 



HORTICULTUEE 



simply sports or mutations from ex- 

 isting sorts. 



Mendel's Influence. 



I know I am safe in asserting that 

 had not the Mendelian laws of hy- 

 bridizing been made public, the evolu- 

 tion of the sweet pea would not have 

 been so far advanced, for Mendel has 

 taught us that it is useless to expect 

 results in the first generation, that 

 no matter how unpromising the flow- 

 ers may appear, the seed should be 

 carefully saved and sown again and 

 then in the second generation we 

 may be rewarded by the appearance 

 of some new and improved forms or 

 types — according to what we have 

 been aiming for and I know that pre- 

 vious to the knowledge of this law, 

 hundreds of crosses were thrown 

 away every year Instead of retaining 

 them for the breaks which would 

 naturally appear in the next genera- 

 tion. 



To those who have the patience and 

 the garden room to spare, for seed- 

 lings in the course of two or three 

 years do take up a lot of space if the 

 hybridizer is making many crosses, 

 the raising of new varieties is a most 

 Interesting pastime, but it is well to 

 count the cost ere starting, as no re- 

 sults can possibly be attained until 

 the second generation, that is, two 

 years from the date of making the 

 cross, and two or three years more 

 must elapse ere the grower can satis- 

 fy himself that the stock is truly 

 fixed. 



According to the varieties which 

 have been mated, something very fine 

 may appear the first year, that is 

 what is termed in Mendelism first 

 generation, or F. I., but the variety is 

 never fixed and always breaks up in 

 F. 2. or second generation, and I was 

 greatly surprised to observe quite a 

 number of new sweet peas advertised 

 for registration in the trade papers 

 early this spring, as first generation 

 selections, when it is an established 

 and indisputable fact that no variety 

 is fixed in the first generation. 



Problems of the Future. 



Has the sweet pea reached its ze- 

 nith, or are there new forms and col- 

 ors yet to be evolved by the special- 

 ist? Judging by the introductions of 

 the past tew years which includes 

 such magnificent novelties as Elfrida 

 Pearson, Stirling Stent, Thos. Steven- 

 son, Charles Foster, Prince George, 

 Orchid, Decorator and Edith Taylor, 

 just to mention a few, the sweet pea 

 is still in its infancy, and we may 

 hopefully look forward to be yet 

 further delighted with marvelous new 

 shades or types, but so much has been 

 said and written lately about sweet 

 pea diseases that if we would believe 

 all we read on the subject, the days 

 of the sweet pea are numbered. Now 

 I, for one, do not believe this to be 

 the case, for having been in touch 

 with sweet peas practically all my 

 life, I have only observed isolated in- 

 stances of disease nowhere have I 

 ever seen it in the form of a scourge. 

 About this time in some sections of 

 Pennsylvania we lose plants whole- 

 sale, but my observations have led me 

 to the conclusion that this is simply 

 due to extreme heat and drought, and 

 it is worth noting that fall planted 

 peas are less liable to go oft as early 

 in the season as those sown in spring. 



HYDRANGEA MADAME MOUILLERE. 



The illustration shows a truss of 

 this fine hydrangea, one of the French 

 novelties lately introduced. The flow- 

 ers are very large, pure white, with 



carmine point In centre, and form a 

 noble truss. We are indebted to Don- 

 ald McKenzie, Chestnut Hill, Mass., 

 for the photograph. 



this being undoubtedly due to the fact 

 that the former has made better, and 

 in most instances deeper, root growth, 

 the plants being therefore more able 

 to withstand extreme heat and 

 drought. This drying up of the vines 

 I have often heard called blight, but 

 it is simply as I have already stated, 

 the effects of continued dry weather 

 and extreme heat, therefore, when I 

 mentioned disease I had in mind 

 "Streak." Thielavia Basicola, which 

 has troubled so many growers in Eng- 

 land. 



Streak Disease. 



The majority of the scientists who 

 have studied streak disease seem to 

 have arrived at the conclusion that 

 errors in manuring and watering were 

 the cause of the trouble. While lo- 

 cated in England, where I grew sweet 

 peas on a large scale for exhibition 

 purposes, I have in some seasons had 

 many rows of plants flooded for sev- 

 eral days in succession, during exces- 

 sive rainfalls, and yet no bad effects 

 followed, this being doubtless due to 

 perfect drainage and deep trenching. 

 The fact, therefore. leads me to the 

 conclusion that the wrong use of ma- 

 nures may be the source of the 

 trouble. We are told that all nitro- 

 genous manures must be withheld 

 from the sweet iiea, for as it lielongs 



to the leguminosae family of plants, 

 all of which are capable of assimilat- 

 ing the free nitrogen of the atmos- 

 phere, it is unnatural to feed it ni- 

 trates, as by so doing the nitrogen 

 gathering bacteria in the root nodules 

 die of inanition and the plant is 

 therefore susceptible to disease. 

 Therefore, where disease has pre- 

 vailed it is well to avoid the too free 

 use of farmyard manure. If the soil 

 must have humus, apply the dung to 

 the previous crop, or use it only in a 

 thoroughly rotted condition, as in 

 that state most of the nitrogen will 

 previously have been liberated. 



A CORRECTION. 



HoRTICrLTURE; 



Gentlemen— In your publication of 

 July 12th. in your notes about Saint 

 Louis, you have a statement to the ef- 

 fect that Mr. W. S. Wells has formed 

 a partnership with me in the land- 

 scape business. Though Mr. Wells 

 will become connected with me this 

 month in the capacity of superinten- 

 dent, there is no partnership formed 

 as you have stated. 



Trusting that you will correct this 

 in your next issue, I am. 

 Yours truly, 



CHARI.es W. Fir.LCRAF. 



