THE HOP PLANT. 61 



16. Forficula auricularia, the earwig, has occasionally ap- 

 peared in large numbers in the hop gardens of the Unter- 

 franken district, and devoured large holes in the leaves. For 

 catching them the use of suspended glasses filled with water 

 and syrup, or baskets or paper bags filled with fresh moss, 

 has been recommended.^ 



17. In 1887 great damage was committed in Alsace by 

 caterpillars of the cherry moth, Geometra hirtaria (Dr. Blo- 

 meyer. Die Gultur der landwirthschaftlichen Nutzpflanzen). 



The stem of the hop plant is endangered by the caterpillar 

 of the hop worm {Botys silacealis Hub., B. lupulina CI., B. 

 nubialis Hbn.) and of Otiorhynchus Ligustici L. 



1. Botys silacealis. The brown nocturnal butterfly lays 

 its eggs on the young juicy tendrils of the hop in the month 

 of June. The caterpillars soon hatch out and bore into the 

 stem, which they mine in a downward as well as an upward 

 direction, several being often found in a single stem. The 

 affected plants become sickly, a condition manifested ex- 

 ternally by retarded growth and a decreased putting forth of 

 laterals, the latter, together with the cones they bear, not 

 infrequently falling off. 



In September the grub leaves the stem and bores a hole 

 in the hop pole, where it passes the winter. In wired gar- 

 dens, however, it either remains in the stem of the hop or 

 else seeks out a sheltered spot for hibernating. To eradicate 

 this dangerous insect the building of fires in hop gardens at 

 the time the butterfly takes wing has been recommended, the 

 insects, attracted by light, perishing in the flame. The bine 

 should also be cut off close to the ground and burnt as 

 soon as the harvest is over, in order to destroy any remaining 

 larvae. Particular attention must be devoted to the poles, 

 since it is in these that many of the insects winter ; passing 



1 Frank and Sorauer, Jahresbericht des Sonderausschusses fur Pflanzen- 

 schutz, 1895 



