718 NARRATIVE AND ITINERARY 
the guidance of Professor Lawson to study the botany of the Port 
Jackson neighbourhood, including the National Park. Another 
important botanical party, under the direction of Mr. Maiden, visited 
the Bulli Pass and the Cataract Dam, passing through interesting 
country and a rich fern vegetation. Mr. Maiden also conducted the 
botanists over the Sydney Botanic Gardens and gave a special exposition 
of the Herbarium. 
Of special botanical interest was the excursion from Brisbane to 
Nambour and the Blackall Ranges, showing sugar-cane cultivation and 
many ferns, aerial orchids and other characteristic plants of the upland 
gullies. 
¢ Before the regular work of the Association began several members 
of the Agricultural Section took the opportunity of gaining some 
acquaintance with the special conditions of farming prevailing in 
Australia. 
The chief questions that occupied the attention of the Section both 
im session and out of doors were dry farming, irrigation, and the breed- 
ing of cereals. In South Australia dry-farming methods were receiving 
a searching test because of the prevailing drought. Notwithstanding, 
the wheat after fallow showed little sign of flagging, and impressed 
everyone by its brilliant green colour. Visits were paid to the Rose- 
worthy Experimental Farm in South Australia and the Werribee Farm 
in Victoria. At both places experiments were in progress to illustrate 
the effects of various cultivations and of taking a fodder crop before 
the wheat. This raises one of the most important problems. in 
Australian wheat-growing, the maintenance of the fertility of the soil 
under continuous cropping. At present it is contended that the system 
of alternate wheat and fallow, still more so the rotation of wheat, 
stubble grazed by sheep, fallow, does not result in any diminution of 
the nitrogen content of the soil. Accurate data, however, are lacking, 
and as it is difficult to understand how the normal recuperative actions 
in the soil should be sufficient to maintain the stock of nitrogen it is 
desirable that this question, fundamental for the future of Australian 
farming, should be submitted to rigorous examination. Dry-farming 
problems were discussed generally by the President, and in a valuable 
paper by Dr. Lyman Briggs, who summarised the extensive investiga- 
tions on the water requirements of plants that have recently been 
carried out at various stations in the Great Plains of North America. 
Several of the points brought out—the comparatively low water require- 
ment of the millets and sorghums and the great variation in the water 
requirements of various strains of lucerne—are likely to become of 
practical value. As regards irrigation, in addition to the discussion at 
Melbourne, the Members of the Section visited the small irrigation 
colonies on the lower Murray, the colonies at Bacchus Marsh and 
Werribee, near Melbourne, and the great Yanco settlement in New 
South Wales, where a meeting was also held and papers read. On the 
subject of cereal-breeding a fruitful discussion took place in Sydney. 
Mr. Beaven brought out the importance of what he terms the migration 
factor, not only in determining the yield of a given variety, but also 
as a means of picking out the high-yielding varieties among the great 
