38 BULLETOr 1082, V. S. DEPARTMENT OF AGRICULTURE. 



At Bellingham, Wash., broken tulips have not been grown, and 

 the stocks, many of which have been grown there for 15 years, num- 

 bering between 250 and 300 varieties, have not broken. 



Any self-colored tulip (and all tuhps grown from seed are self- 

 colored) may become broken. The statement is sometimes made 

 that the single early tulips do not break, but this is true in the florist's 

 sense only. These break just as truly as the others, but they give 

 in the breaking no spectacular patterns such as are found in other 

 groups; on the contrary, the brilhancy of their floral coloration as well 

 as their general vigor is reduced. Consequently, the broken plants 

 in this group are rogued out of the stock. 



The cause of breaking in tuhps has not been demonstrated, neither 

 has it been investigated until recently with the idea of its disease 

 origin in mind. Nor for that matter has the real cause of mosaic 

 diseases in other plants been demonstrated, although extensively 

 studied. The essentials of communicability, effect on the host, 

 carriers, and preventive measures are well worked out, however. 

 As in tobacco, it is probable that here again the aphis is the main 

 carrier of the disease. Fortunately the aphids have never been 

 numerous in the bulb fields at Bellingham, Wash. 



With this information before him the bulb grower should consider 

 carefully before he attempts to introduce broken stocks into his 

 plantings. It is known that the disease is communicable to self- 

 colored stocks. There is, consequently, grave danger of his self- 

 colored stocks becoming ruined if broken stocks are introduced, 

 for when once broken they can be sold only as mixed tulips. The 

 production of bulbs of these mosaic varieties should not be attempted 

 except at safe distances from the regular self-colored stocks. 



A peculiar trouble sometimes occm"s in tulip bulbs when grown 

 under adverse conditions which has caused growers concern because 

 interpreted to be a disease. It manifests itself in the form of an 

 imperfectly filled bulb coat. The base of the bulb may be quite 

 normal and weU fihed but reduced in size, but the tip may be empty 

 and wrinkled, as is well brought out in Plate VII, Figure 1. This 

 condition has been observed in many varieties on the Pacific coast 

 when planted shallow and late on very light soil that dried out too 

 quickly in the spring. 



WHY SOME VARIETIES ARE CHEAPER THAN OTHERS. 



It is not necessary to discuss values in novelties or new varieties 

 of which only limited stocks are available. Here the law of supply 

 and demand and a desire for the new govern, as in any other com- 

 modity. 



Leaving aside entirely the facts of actual merit, popularity, and 

 consequent general demand, there are some varieties which can 



