Field budding is a method of grafting grape vines, used especially in coastal California, in which the rootstocks are planted and allowed to grow for nearly a whole season before the grafting takes place. Then, rather than making a traditional woody graft, the worker in early September attaches a small chip (containing only one dormant bud of the desired fruiting variety) to the rootstock at just above ground level. The cambium layers must be held in good contact so that, as the vine continues to grow, a callous material forms around the cut, sealing it permanently. The chip is held in place and sealed from drying by wrapping the stem with a small piece of rubber strip. After this, the whole stem of the plant, including the budded section, is covered with several inches of loose earth, to keep the new bud shaded and cool so it will not begin to grow immediately. The vine then finishes its normal period of autumn maturation and goes into dormancy within several weeks. It is not touched again until the following spring. In spring, the worker uncovers the loose earth exposing the wrapped bud on the stem of the rooting. She cuts the rubber tape and checks to see that the bud has indeed become calloused firmly onto the stem. If so, she then cuts the vine off just above the bud so that there is no viable part of the vine left above the bud except the bud itself. Now, as the roots begin to allow sap to push upwards, the only bud available for growth is that which was added the previous September. This bud begins to grow, elongating into a vigorous shoot which can often grow to three feet in length within six weeks. Because it is delicate and friable, the new shoot must be tied every few inches to prevent breakage caused by the wind. It is this shoot which becomes the trunk of the new vine during this, its first year of active growth. (Wine/Other)