80 Journal of the Department of Agriculture. 



WALNUTS. 



Note by I. Tribolet, Chief, Division of Horticulture. 



A GOOD, deep, fairly loamy soil, with a certain percentage of lime, 

 and a consistent water content provided either by the heavens or by 

 irrigation, are required to grow the walnut to the best advantage. 

 Drainage must be good, but a uniform and abundant supply of soil 

 moisture is necessary in winter as well as in summer. This is one 

 of the main requirements of the tree. With abundance of water 

 groves are sometimes very successfully g*rown under sward, or with- 

 out much cultivation, but if water is not very plentiful good cultiva- 

 tion should be practised. The softer-shelled varieties are somewhat 

 more delicate than the hard-shelled varieties. 



When propagating from seed, especially if the trees are to bear 

 as seedlings, only the finest well-matured nuts should be used, and 

 these should be selected from the best and most prolific trees in the 

 grove. About June and July the nuts are spread out in a single 

 layer on a well-drained piece of ground dug out to a depth of 3-4 

 inches. For good drainage a slope is preferable. After digging out 

 the ground spread a layer of sand an inch or so thick in the hole 

 and put down the first layer of nuts, then another layer of sand a 

 couple of inches thick, then another layer of nuts, and so on until 

 there are three or four layers of nuts ; the sand will then be forming 

 a moimd some few inches above the general level of the soil. This 

 must be watered now and again to keep the sand fairly moist. As 

 soon as the nuts begin to split and throw out shoots they may be 

 planted out in the nursery rows, 3 feet between the rows and about 

 1 foot 6 inches apart in the lines, and allowed to grow in this state 

 for a season or two, when they are planted out in orchard form. If 

 seedlings are required for grafting in the nursery rows to other 

 varieties they should be left for another season or two, and then 

 planted in the orchard and tended after the manner of any other 

 standard orchard trees. Although most of our groves now in bearing 

 are seedlings, the tree is much improved by grafting on suitable 

 stocks. One of the best stocks at present known is the Northern 

 Calif ornian Black Root (Jtiglans liindsii). Varieties grafted on 

 selected seedlings of this tree give thrifty vigorous plants, more 

 resistant to excessive moisture and drought than when grafted upon 

 almost any other root. It is not susceptible to root rot, and in every 

 way gives satisfaction. In the case of walnuts grafting is more 

 practised than budding. When budded, the flute or whistle bud is 

 mostly used. A good grafting wax is as follows: 3 to 4 lb. of resin, 

 1 lb. beeswax, 1 pint boiled linseed-oil. The resin and wax are 

 thoroughly melted and mixed with the oil when in a liquid condition. 

 Very little pruning is required after the tree is shaped. Pruning 

 out where too thick is about all that is needed. Where the tree does 

 well, the distance when planting should be from 30 to 50 feet apari, 

 and even more under very favourable conditions. 



From the rather limited experiments that have been carried out 

 in manuring, the results go to show that ordinary stable marnre is 

 as good as anything that can be used. The principal requirements 

 are nitrogen and phosphoric oxide ; these are generally supplied by 



