432 SECTIONAL TRANSACTIONS.— K. 



Mr. G. E. Blackman. — The techniqiie of pastureland experiments 

 (11.20). 



For the proper study of most pasture problems some method of measuring 

 productivity is essential ; the accurate assessment of yield presents, however, 

 a number of difficulties. In view of the profound effects that the period of 

 grazing and its intensity may have on the sward, estimates of yield obtained 

 by continuous cutting are liable to give misleading results. In order to 

 simulate as far as possible grazing conditions it is necessary to carry out 

 somewhat complex experiments. The design of these should embrace 

 large plots to eliminate edge effects, while the replication should be sufficient 

 to ensure that each block of plots is grazed during the major part of the 

 experimental period and only cut for the determination of yield at infrequent 

 intervals. Where a high degree of precision is required the stock used 

 for grazing plots with different treatments must be kept for a preliminary 

 period on comparable herbage. The results may also be affected by the 

 type of stock used, and other factors dependent on seasonal differences. 



Mr. Martin Jones. — The response of plants to animal interference 

 (11.50). 



In pastures there are various types of plants all competing for plant food. 

 Which type succeeds best depends to a large extent on its reaction to the 

 grazing animal. 



During periods of scarcity animals are forced to eat down too hard such 

 plants as are growing at that time, with the result that if such conditions 

 recur frequently the most useful plants are first of all weakened and ulti- 

 mately lost from the sward. Such periods of scarcity of green fodder, be 

 it due to cold weather or to lack of moisture, generally coincide with critical 

 periods in the life-cycle of such useful plants. 



On the other hand, the protection from grazing obtained by certain other 

 plants due to their lack of palatability enables them to increase unduly. 



Left to nature the animal thus favours the least valuable plants, whereas 

 with proper manipulation of the grazing — aiding the animal at certain times 

 of the year and providing for it at other times — the farmer can control the 

 destiny of his sward. 



General Discussion on Pasture problems (12.20). 



(concurrently with above session.) 



Mr. K. P. Biswas. — Some observations on the aquatic and marsh 

 plants of India and Burma (lo.o). 



The aquatic and marsh vegetations of India and Burma have a very wide 

 range of variation, dependent as they are on diverse climatic conditions in 

 these two vast countries. The extensive open coastline harbours an inter- 

 esting marine flora. The asstuvarian areas stock a rich mangrove vegetation. 

 The lagoons and inner brackish water and swamps sustain a curious mixture 

 of freshwater and saltwater plants. The hill streams, although scarcely rich 

 in vegetable growth, not infrequently have their beds covered with Iron 

 bacteria, Batrachospermum and Sirodotia. Numerous freshwater lakes, 

 tanks, pools, and puddles scattered all over the plains are storehouses of 

 dense masses of vegetation, both Phanerogams and Cryptogams accommo- 

 dating themselves in a harmonious community. 



