PESTS OF THE HOP CROP 151 



the young hop cones. They are hollow, and constructed 

 somewhat like a football, that is, one case inside another. 

 The outer case is made of dark brown, strong material 

 (Fig. 78&), and acts as a protective coat for the delicate, 

 transparent, pear-shaped case (ascus) inside (Fig. 78a). The 

 latter contains within it eight spores (Fig. 78c) (ascospores) 

 about the shape and size as those produced upon the 

 upright threads mentioned above, only they do not germi- 

 nate so readily. These double cases, with their spores, are 

 produced in large numbers in late summer or autumn in 

 a badly affected garden, and fall upon the ground with the 

 dead leaves, and the spores within are shot out into the 

 air, and are carried to the young bines and leaves, which 

 are then growing from the hill. Thus we see why it is that 

 mold generally commences close to the ground and spreads 

 upwards, and why there are "moldy places" in the gardens, 

 where the malady begins almost every year. 



Remedies It will be understood from the fore- 

 going account that we are dealing with a living pest, 

 and that it is just as impossible to create "mold" as it 

 is to manufacture aphides or lice. Various methods 

 of cultivation and treatment of the hop plant and gar- 

 den may be conducive to the growth and development 

 of the "mold" fungus, but unless its spores are present 

 or are introduced into the garden from outside, spots 

 cannot occur. Whatever remedies are adopted, it is 

 absolutely essential that they should be begun early, 

 as neglect means failure. The pest soon becomes 

 established and is then difficult to eradicate. 



I. Although the complete destruction of hop 

 mold is unattainable, every effort should be made to 

 diminish its prevalence by burning all badly affected 

 vines and leaves. This practice should especially be 

 carried out in cases after a bad attack, where the hops 

 have been not worth picking on account of moldiness. 

 The vines should on no account be left lying about, as 

 the spore cases are produced in thousands and fall upon 

 the ground, only to remain a certain source of infection 

 for succeeding years. The application of gypsum to 

 the soil is said to be beneficial in such circumstances, 

 but no trustworthy experiments upon this matter have 



