10-.' 



H E T I C U L T U E E 



August 3, 1918 



Time Between Pollination and Fertilization 



This period differs greatly in plant species from a 

 few hours to many months. In the French iris, in warm 

 sunny weather it is thirty-six hours in my location — 

 New Hampshire, latitude 4-1 N., elevation 1100 feet. 

 In forty-eight hours the stigmas will have wilted to 

 the state in Figiire-7-at-A-, in six days to that at-B-, 

 in seven days to that at-C-. In nine days the develop- 

 ing ovary will begin to look like a seed pod, as shown 

 at D^ in the same\ figure. Go over the rows every morn- 

 ing, cutting off the stigmas that have reached the con- 

 dition B-, at the level of the stumps of the perianth 

 se.gment. The object is to prevent dew or rain from 

 injuring the developing seed-pods, as they will often do 

 if allowed to remain in contact, ^^'lieu the dried 

 stumps of the sections of the jierianth have reached the 

 state at -D- cut them off at the dotted line in the figure. 



Don't 



pollinate iris flowei's when wet with rain or dew, or 

 when rain seems near. Avoid pollinating in intensely 

 hot weather, for then the stigmas wilt so quickly the 

 pollen tubes do not reach the ovules. Again, a very 

 wet season may cause a total failure. This happened 

 to me in 1915. Out of several thousands of crossings 



no satisfactory seeds were saved. Of course there may 

 have been other causes that were overlooked, but pre- 

 vious wet seasons had suggested (lam])ness as the chief 

 cause of failure. 



Bagging the Crossed Flowers 



In directions for hybridizing you will find statements 

 showing the necessity of keeping the crossed flowers in 

 paper bags. They are an awful nuisance with iris and 

 with this flower not absolutely necessary. Better cross 

 so many flowers, the eases of accidental contamination 

 will nut seriously affect the records. 



What Proportion of Pollinations Will Succeed 



Tliis question C(.)uld only Itc answered by a dreary 

 lot of statistics, as uninteresting as Homer's catalogue 

 of ships or ^\^^itman■s list of occupations in Leaves of 

 Grass. Moreover, the results of one man's work might 

 differ widely from another with climate and other fac- 

 tors. What may well be written is that some crosses 

 are more successful in my locality than others. As an 

 example, Kochii is named. Desiring to get its mag- 

 nificent color in a tall, large flowering plant, it was 

 crossed several times with some of the finest strong 

 growing kinds, including some very vigorous hybrids 

 raised here. One year fifty fine seed pods formed, but 

 they were later found to be hollow shams, containing 

 not one good seed. In other years the results were no 

 better. Purple King looks like a Kochii hybrid, but 

 as it lias lost the deep tint, it has been cast out of my 

 garden. We need a tall growing large flowered iris, 

 the color of Kochii; another with the upright segments 

 whrte and the falls like Kochii ; and another with tiie 

 colors reversed. Who will breed it for us? 



Tarn worth, N. H. 7 V i- 1 t^^^w 1^0 UUv6 



{To he continued) ^^^, 



