CULTIVATION. 255 



plant remains in full bearing. Even on this point no general 

 rule can be laid down, all that is definitely known being 

 that there are three main periods into which the productive 

 life of the hop plant maybe divided, viz., the increasing, 

 maximum and decreasing stages. Under normal conditions 

 the plant attains its maximum bearing power in four or 

 five years after planting, remains in full productivity for 

 another eight or ten years, and then in many cases the 

 crop begins to diminish. Experience shows that beyond 

 the age of twenty years the yield becomes irregular and 

 uncertain, though of course there are exceptions, such as 

 those gardens that still continue to crop well at the age 

 of thirty years and more. On the other hand, many in- 

 stances are known where the plants are so weakened by 

 repeated attacks of disease or other severe injury that they 

 have to be prematurely broken up or replanted ; and it 

 frequently happens, in damp situations especially, that the 

 hops lose their productive power in eight to ten years. 



When only a few of the plants here and there in a 

 garden are seen to be falling away in point of cropping, 

 it is not advisable to condemn the whole, since in such 

 event it will be sufficient to replace the weakly plants by 

 vigorous, new sets. If, however, the decrease is found to 

 extend to the majority, it then becomes time to gradually 

 rejuvenate the garden, or plant a fresh one. Eejuvenation, 

 which is chiefly confined to small plantations, consists, in 

 replanting every other row, say the odd numbers, one, three, ' 

 five, etc., one year, and in a subsequent year treating the 

 even-numbered rows in the same way, the object of this 

 procedure being manifestly to guard against a total failure 

 of crop. 



If the whole of the garden is grubbed up at the same 

 time, and is to be replanted with hops, it must be immedi- 

 ately trenched, manured, and the new sets planted ; or, if a 



