Impact of irrigation on farms

Press, Volume CXIII, Issue 33419, 28 December 1973, Page 6

Impact of irrigation on farms

Ministry of Agriculture and Fisheries economists have given some details of the sort of impact that they expect irrigation will have on farms in the central plains and Rakaia-Pendarves-Seatield districts in Canterbury.

One such representative property is of 676 acres on the light Lismore soils in the central plains area. There are some 114,000 acres of these soils in the district a.id this farm is the average for properties ranging from 500 to 900 acres on this soil type. Currently, ' apart from having 25 acres in wheat and barley, it is basically a grazing proposition with 125 acres in lucerne and the balance of the area in grass. It is carrying about 1730 breeding ewes and breeding its own replacements. On average the lambing percentage is 105 and the ewes clip 4.4 kilograms of wool, but in recent droughty years these levels of per-

formance have not been reached.

Assuming that the farmer is a moderate irrigator and will be “Mr Average’’ when irrigation comes ,to the district, he will still remain a livestock farmer. Then 305 will be irrigated, of which 200 acres will be in pasture and the balance in lucerne. It is not expected that irrigated pasture will have to be renewed. With irrigation 2450 breeding ewes will be carried, with replacements still being bred, and in addition 74 weaner cattle will be overwintered and fattened. Total stock units carried at 3135 will represent an increase of 50 per cent. This farmer will still grow about the same amount of crop as before and it will not be irrigated, although technically, cropping might be expanded.

Under the new system net farm income will rise to an expected $18,500 compared with $9OOO under dryland farming. It is anticipated that this farmer would spend about $23,500 on border dyking and fencing and about $9OOO on extra stock.

Another sort of farm described is of 369 acres and is the average for some 23 farms occupying 8487 acres on the better soils in the region — Hatfield silt loam, Barrhill sandy loam and the best of the Templeton and Waimakariri soils. At present on this representative farm some 210 acres are in crops, including wheat. barley, peas, potatoes, and ryegrass and clover for seed. Some 140 acres are in grass and 10 acres in lucerne.

Some 355 two-year ewes are bought in, some 150 ewes are sold with. lambs at foot and 100 hoggets are wintered. Thirty weaner cattle, also bought in, are taken to 18 to 20 months and 26 weaners up to a year. A total of 794 stock units are supported. With irrigation about 300 acres will be watered, The area In crop will go up to

267 acres, with 247 acres being irrigated. At the same time the area under grazing will drop to 93 but 53 will be irrigated. Most of the reduction in the grazing area will be taken up by white clover for seed, which will be doubled in area. Sheep numbers will go up from 627 to 1032, with' 600 breeding ewes being; run. 200 ewes wintered and sold with lambs at foot and 200 hoggets wintered. Sixty weaners will be carried to 18 to 20 months and' 40 weaners up to a year. In total, stock units carried. will have increased from 794 to 1326. On this farm net income under dryland fanning is about $10,300. Under irrigation it is expected to be about $22,000. The development involved! in converting to irrigation! is expected to cost $33,000,1 including $5300 for extra livestock, and the simple; return on the investment.! with a 10-year development! period, is put at 36 per cent.; Another farm type cited is in the smaller of two groups of farms on basically Chertsey soil in the RakaiaPendarves - Seafield area. These farms vary in area from 50 to 600 acres and the average size is 414 acres.

Under irrigation there will be a 67 per cent increase in cropping, with the major increase again being in production of small seeds. Thirty-eight per cent of the farm will then be in crop. At the same Jjme sheep numbers will' rise from 1350 to about 1850. About $21,000 will be spent on border dyking and $6OOO on extra livestock Net income is expected to double, rising from $7853 to $15,809, giving a simple return on capital invested in development of 29 per cent.

The larger farms on the same soil type average 842 acres and here under irrigation the area under crops will increase by 66 per cent, but will still represent only 25 per cent of the farm area. Stock units will;' rise by about 48 per cent, j Net income under irriga-i tion is estimated to, be' $24,600, an increase of 120: per cent over $ll,lOO under existing conditions, and for an investment of $43,500. the simple return is calculated to ba 31 per cent, I 1