Selection of good scionwood and bud wood, a very important matter, is made according to definite standards.  Some plants graft better if wood is used that has two seasons’ growth, but, in general, wood of the current season’s growth is used.  It must have reached its maximum possible maturity before it is cut.  Also, some attention should be paid to the vigor of the growth which it has made during the season.  For instance, in choosing between wood which has made only two or three inches’ growth and that which has made a foot or more of growth, both being equally sound and mature, the more vigorous should be chosen.  Attention should be paid to the development of the buds, which should be plump and never immature.

It is advisable to label scions before they are stored to avoid the confusion that will result if they are mixed.  I find that the best method of doing this is to get a sheet of zinc, from 20 to 30 gauge thick, and cut it into strips one inch wide by one and three-quarters inches long.  I bore a small hole in one corner of each tag, through which I thread 18-gauge copper wire, doubled and with the bottom loop folded over (see page 40).  In preparing these tags, it is important to remember that both wires must pass through the hole in the metal tag, otherwise, the slight movement due to winds will cause the metal to wear through.  Two wires prevent this action indefinitely.  Since a small wire cuts through a zinc tag in one or two years, heavy wire must be used.  Wire such as I have indicated is satisfactory.  I print the necessary information on each tag with a small, steel awl, and such labels are still legible after twenty-five years.  Copper, brass or aluminum would also make good tags, but these metals are more expensive.  Of course, these tags may be used for small trees as well as grafts and scionwood and it is always well to do a good job of labeling all work, since many errors may result from disregard to this important detail.

In the north, the time to graft nut trees is when the cambium layer of the host, or stock, is active, which is usually during the entire month of May.  This cambium layer consists of those cells lying just inside of the outer bark, between it and the woody part of the tree.  When these cells are active, the inner side of the bark feels slippery and a jelly-like substance can be scraped from it.  Although this is the state in which the stock should be for grafting, the condition of the scions should be almost the opposite, rather dry and showing no signs of cambium activity.  The bark should cling firmly to the woody part of the scions, whereas the bark of the stock should slip off readily.  Another good and fairly satisfactory rule is never to graft the stocks of nut trees until after the young leaves appear.