APPLE WEALTH

Evening Post, Issue 122, 26 May 1933, Page 14

APPLE WEALTH

ITS FOUNDATION

VVHAT IS THE BEST STOCK?

About half a century ago Northern Spy was the chief word in the apple leligion of the Auckland district. In Rome of the northern districts it is still grown for its fruit, but it is as a stock that Northern. Spy (likfc older northern wonders) has conquered New Zealand, and it is as a stock that its value is assessed in the new exporting apple industry of today. Research is creeping up on. that valuation. The Plant Research Station at PalmerstdH North, through Messrs. H. H. 'Allan and C.E. Woodhead, makes what may be called'an interim report on apple ,stock experiments that will take time to complete. Northern Spy, which is aphis-resistant, is the major stock now used in New Zealand apple orchards. The Research Station is studying nine types, not all of them Northern Spy apples. Features of these typos under test are described in detail in the "New Zealand Journal of Agriculture." Type 1 and type 5 show the largest leaves;, of the latter it is written: "A promising type, but possibly not a Northern Spy, although it appears to bo aphis-resistant." '.. In the course of their report Messrs. Allan and1 Woodhead state:- —"la a Riwaka (Nelson) orchard it was noted that certain Stunners on a non-aphis-proof (probably, seedling) stock were superior in general vigour and cropping capacity to those on Spy stock. The' growth of new wood in the Stunner on Spy stock decreases rapidly when fruitbearing commences, and eventually comes almost to a standstill in spite of severe pruning. This stock would appear to be worth testing as a stock for the Stunner variety in orchards in this and similar districts. A parallel case was noted in an Ettrick (Otago) orchard. It "was noted also that in certain orchards Delicious worked on Northern Spy had a very insecure roothold. It would appear that under certain conditions the Northern Spy should 7jo replaced in these varieties by other stocks. At "Mapua some Jonathan trees on a seedling stock were much larger and carried heavier crops than those on Northern Spy under similar soil conditions. Eoot cuttings have been obtained from the stocks above mentioned. "The evidence of the trial blocks at tho Cawthron Institute orchard also suggests that trees on tho Double Vigour and on certain seedling stocks may have, under the conditions of that orchard, more vigorous growth and come into bearing later than those on Northern Spy. It may be that on the comparatively poor lands in parts of the Nelson apple-growing areas a more vigorous stock than Northern Spy is required for varieties of weaker habit, such as Cos's Orange and Jonathan. This view is supported,by the fact that when odd trees on seedling stock' are met with on the same class of soil they show superior growth, further, seedlings are usually deep-rooting and wenfurnished -with fibrous roots, whereas tho Northern Spy has a shallow and comparatively coarse root-system. "It is not to be inferred that wo are recommending tho use of mixed collections of seedling stocks. The different types of these need isolation and standardisation with a view to testing their capacities. It is also to bo said thiit among the Northern Spy types we may possess such as have the required vigour combined with the other desirable Northern Spy qualities. But the general statement may bo made that no single typo of stock can bo expected to produce tho best results with all varieties. A point that is engaging our attention is the effect of double working oa stock and scion; there are indications that this may at times bo a. valuable practice. "Even when tested types of stock are available, it will remain of great importance that very accurate grading of nursery matorial be made in order to secure close uniformity of growth. .This1 is true even where clono stocks are used. This need for accurate grading has not, perhaps, always been recognised in nursery practice, find the lack of attention to it may account for a good deal of the diversity n£ growth on what is taken t<r bo a single line of stock."-