UNIVERSITY OF CALIFORNIA Agricultural Experiment Station College of agriculture e. j. wickson, acting director BERKELEY, CALIFORNIA CIRCULAR No. 26 (September, 1906.) SELECTION AND PREPARATION OF VINE-CUTTINGS. BY FREDERIC T. BIOLETTI. One of the most important factors in determining the profitableness of a vineyard is the choice of the cuttings which are used to start the vineyard. This factor is very generally neglected, or when a choice is made it is often not the best. Any one who will carefully examine the vines in a vineyard cannot help being struck with the great variation in the amount of crop on different individual vines. Sometimes this variation can be traced to differences in pruning, to accidental injuries, to more or less irrigation, or to variations in soil and position. There is, however, a good deal of variation which cannot be ascribed to any of these causes and which exists in every vineyard, no matter how uniform the conditions or how careful the cultivation. This variation is something which is inherent in the vine and can- not be overcome by any cultural method. It is much greater in some varieties than in others. With some varieties it is so great that certain vines are recognized as almost sterile and are commonly called ' ' mule ' ' vines in California. With other varieties the variation is much less noticeable, but is none the less real, and by weighing the crop of each vine in a row it will be found, even with the most uniform producers, to exceed 50 per cent. If every vine in the vineyard bore as much as the vine w T ith the heaviest crop the total production of the vineyard would be much increased. By grafting the poor bearers with cuttings from the best bearers the crop in a vineyard has been more than dou- bled. Vineyards of unselected Cabernet produce on the average about two tons to the acre. Cabernet vineyards from carefully selected cut- tings have produced nine tons. Owing to the great natural fertility of most of our Californian vineyards, due to favorable soil and climate, these facts have not re- ceived the attention they deserve. In most parts of Europe, and even in South Africa, more care is taken in the selection of cuttings than here. In many vineyards the vines bearing the best crops are marked and cuttings taken only from these. In others only those cuttings are used which are made from bearing wood; that is, from canes which have borne grapes, as shown by the remains of the bunch stalks, or by the position of the cane on the vine. It is perhaps not riprht to say that no choice is exercised in the selec- tion of cuttings in California. There is inevitably some choice, though principally unconscious and generally harmful. The man who is mak- ing cuttings will, if he has no other standard, choose those canes which he can work up with the greatest ease. These are the long, unbranched canes from the most vigorous vines. Such canes are usually suckers or wnter-sprouts, the least fruitful on the vine, and the most vigorous vines are generally those which have produced the fewest grapes. Such selection as this cannot fail to be harmful, especially with the finer va- rieties, which vary more than the common, and must finally result in the deterioration of all varieties. The ordinary European method of simply marking the vines which bear good crops the year the cuttings are taken is imperfect and can do no more than keep the varieties from deteriorating. By more care- ful selection, continued systematically for a series of years, it has been proved possible to greatly increase the bearing qualities of certain va- rieties. Other qualities besides that of more or less productiveness could undoubtedly be influenced by the same means. In this way nu- merous variations of the Pinot or Burgundy have arisen. These varia- tions differ from the type in color, acidity, time of ripening, and even in flavor. It would probably be possible to produce a loose bunched Tokay, a close bunched Zabalkanski, or a large fruited Sultanina in the same way. There is no quality, however, which varies so much with individual vines as that of bearing, and there is no quality that is so quickly and easily influenced by cutting selection. It is this quality, therefore, which should receive most attention in choosing our cuttings. The modification of other characteristics is the work of the plant breeder and is too slow, difficult and uncertain for the practical grape grower. It is, moreover, at least in the case of wine grapes, unnecessary, for we can find almost any quality we want among the two or three thousand known varieties of wine grapes, but unfortunately not always com- bined with high productiveness. The most promising means of obtain- ing the rara avis we desire is to commence with a variety possessing the necessary flavor, color and chemical composition and by proper cut- ting selection to bring up its productiveness to the desired degree. It would be much easier to "grade up" the Cabernet until it bore crops equal to those of the Carignane than to attempt to improve greatly the flavor and color of Carignane by selection. Method of Selection. The first question to be settled is, of course, what variety should be chosen. This will depend on whether it is in- tended to raise table, raisin, or wine grapes, and if wine grapes, on the kind of wine desired, sweet or dry, red or white, and also on a multi- plicity of local and market conditions.' The question of variety is too Large and complicated for treatment here and has already been given much attention in various publications of the Station. Only the ques- tions regarding the means of obtaining cuttings capable of growing into strong, heavy bearing vines will be considered here. The Locality. Any locality where the vine grows vigorously and ripens its wood regularly will produce good cuttings. As a rule the warmer localities produce the best wood, heavy, firm and well nour- ished. The canes on vines grown very near the coast, as at Berkeley, are often soft and pithy. Certain varieties such as Refosco and Almeria do not ripen their wood well in the cooler parts even of Sonoma and Santa Cruz counties where they are exposed to frequent sea fogs during the summer. Being immature when the frosts cause the leaves to fall, the canes are easily attacked by saprophytic fungi. The work of these fungi is often seen in the blackened or mottled ap- pearance of the canes. Any discoloration of the canes is a bad sign, whether it is caused by fungi which only attack imperfectly matured wood, or by parasitic fungi, such as oidium, which may occur any- where. With the exception of a few isolated localities quite near the coast, it may be said that good, well ripened cuttings may be obtained from any of the vine-growing regions of California. Vine Diseases. An exception should perhaps be made to this state- ment as regards localities where the so-called Anaheim disease is prev- alent. Until we know more about that disease it is wiser to avoid obtaining our cuttings from such regions. That this disease can be transported and communicated by cuttings is perhaps not thoroughly demonstrated, but at all events the disease results in poor growth and poor wood, and cuttings from diseased vines cannot be expected to give the best results. With regard to other diseases there need be no fear of their intro- duction into the vineyard by means of cuttings. Phylloxera can be guarded against by proper disinfection of the cuttings and all other vine diseases, which exist in California, are found in every district. This is not true as regards rooted cuttings. There is no sure and prac- ticable method of destroying Phylloxera on the roots, and rooted vines should be introduced into a new district only with extreme caution. While there need be no fear of introducing Oidium, vine-hoppers, etc., for they exist in every vine-growing region of California, no cut- tings should be used which show distinct signs of their attacks, as such signs are proof that the vines from which the cuttings came were not perfectly healthy, and unhealthy vines do not produce the best cut- tings. The Vineyard. As a rule it is best to obtain the cuttings in the district where they are to be planted, if the desired variety is grown there. The only exceptions to this rule are for districts where Ana- heim, Oidium, or some other disease is so prevalent that it is difficult to find perfectly healthy vines. The locality being decided on, it is not a matter of indifference what vineyard is chosen. Only a well kept, vigorous vineyard can pro- duce the best cuttings. If the vineyard is badly cultivated, the vines mildewed, or the grapes of poor quality, it is a bad source for our cut- tings. A vineyard which has healthy vines producing paying crops of good grapes is the best place to get them. The Vines. Given the locality and the vineyard: from which vines in this vineyard shall we take our cuttings? This is the most impor- tant question of all and that which is most generally neglected. It is hardly necessary to say that no cuttings should be taken from vines which have never produced a good crop. Some such vines exist in nearly every vineyard. A few growers mark such vines and avoid them when making cuttings. It would be better to graft them over or dig them out. Instead of marking the poorest vines in order to avoid them, it is better to marjs the best vines in order to choose them when making cut- tings. When the crop is ripe and still on the vines the vineyard should be gone over carefully and a sufficient number of the best vines marked to supply the amount of cuttings needed. Only vines showing health, vigor and heavy crop of well-ripened grapes should be marked. A dab of paint on the stake or the stem of the vine is perhaps the most con- venient way of marking. While this will insure our cuttings coming only from vines which are capable of producing a satisfactory crop, it omits one very impor- tant factor — the regularity of bearing. Some vines bear good crop occasionally, or on alternate years. The ideal vine is one which bears a good crop every year. This vine we can find only by keeping a con- tinuous record of its performance. This can be done to some extent by going over the vineyard every year just before the vintage and marking every vine which has a good crop. At the end of four or five years the vines which have borne a good crop every year will show four or five marks, and these are the vines most likely to yield cuttings ca- pable of producing a vineyard of ideal vines. To make this selection most effectively and quickly would require a special vineyard for the purpose. A vineyard of pedigreed vines of all our most desirable varieties would be a most valuable acquisition for the State. Such a vineyard might be started with cuttings selected in the way described, and each variety gradually brought up to its highest possible bearing capacity, by grafting all the vines of each variety with cuttings taken from the vine of that variety which had shown the best and most regular bearing qualities during a term of years. Twenty-five or thirty such vines of each variety would be suffi- cient to maintain and improve the productiveness of all the vineyards in the State if it were used to supply stock to nurserymen and other growers of vine cuttings. This would make it unnecessary to abandon many of the finest varieties of grapes, as has been done to a great ex- tent lately. Pari of the Vine. While any cutting from a good vine is probably better than the best cutting from a poor vine, it is not a matter of in- difference from what part of the vine the cuttings are taken. It is a well established fact known to all skilled pruners that certain buds on a vine are much more likely to produce fruit than others. These buds may be called, from analogy with similar bud on orchard trees, fruit buds. The fruit buds of vines, unlike those of most orchard trees, are not distinguishable by shape or size from wood or sterile buds. They can be recognized only by their position. The buds on suckers (canes from below the ground) or water- sprouts (canes from the trunk or older parts of the arms) are usually unfruitful with most varieties. The only buds which can be depended on to give fruit are those on canes which have grown on wood of the previous year, or as primers usually express it, "fruit spurs and fruit canes consist of one-year-old wood growing out of two-year-old wood. ' ' The canes of such wood are called by the grape-growers of South Af- rica "bearers," and no others are used for making cuttings. Now, while the choice of this wood is perfectly safe, it has not been demonstrated that such choice is necessary. It may be that cuttings taken from heavy bearing vines will grow into other heavy bearing vines whether they have originally been water-sprouts or fruit wood. This seems probable, for in pruning vines it is constantly necessary to use water-sprouts to form spurs for the purpose of replacing lost arms or for shortening arms which have grown too long. Now, while these spurs bear little or no fruit the first year, they give rise to wood the following year, which satisfies the primer's definition of fruit wood, viz., "one-year-old wood out of two-year-old wood," and which is ap- parently as fruitful as any wood on the vine. A sucker, or water- sprout from a fruitful vine, therefore, is to be preferred in making cuttings to a fruit cane from a vine which bears small crops. All canes and all parts of the cane, however, are not equally suit- able for cuttings. Very small, thin canes are apt to be ill-nourished and immature, as are also the tips of better canes. Many cuttings made from such material are apt to fail, or give weak vines. Very large, over-grown cuttings are also to be avoided. Many growers avoid using the two or three buds nearest the base of the cane on the ground that such buds are not fruit buds, but the same reasoning may be ap- plied to this case as to that of water-sprouts. A medium sized cutting between three-eighths and five-eighths inches in diameter is most likely to give good results. Form and Length of Cutting. It was formerly considered good practice to leave a piece of old wood attached to the base of the cut- ting, on the ground that such cuttings always grew. This practice is now very generally abandoned, as it often gives rise to weak and dis- eased vines. The piece of old wood always decays finally, and the decay may spread into the trunk and roots of the vine. A ^ood cut- ting should consist exclusively of one-year-old wood ; that is, the wood which has grown during the current season. The form and length of the cuttings will depend on the use that is to be made of them. If they are to be used as scions for grafting they may be cut up in any way and of any length that is found convenient for handling and keeping them in good condition. If they are to be used for rooting either in the nursery or the vineyard it is most con- venient to cut them up into the exact lengths which are to be planted. The length will depend altogether on the soil and climate where they are to be planted. They should be of such a length that when planted the base of the cutting will be at the level where the conditions are most favorable to root formation. If the base is too deep, it will be too wet and too cold to develop roots. Roots will start higher up and the bottom part will be wasted, or worse still, may decay and injure the vine. If the base is too near the surface the whole cutting may dry out and die before its roots have developed sufficiently to supply it with water. In the moister soils of the cooler districts a cutting 10 inches long is sufficient for direct planting in the vineyard. In the drier and warmer interior a 14- to 16-inch cutting is better, while in the driest soils of the warmest districts it is often necessary to have a cutting 18 to 20 inches long. For planting in the nursery a 12- or 14-inch cutting « is about the most convenient. If the soil of the nursery is wet and cold more of the cutting should be left above ground; if, on the contrary, the soil tends to be hot and dry the cutting must be planted deeper and even covered up completely. It is not necessary, or possible, to make every cutting of exactly the same length, because they should all terminate at each end at a node. A vine cane consists of nodes where the buds are and internodes be- tween the buds. The pith is interrupted at each node by a woody par- tition which extends through the cane at each bud. In making a cut- ting, therefore, we should cut exactly through a bud both at the top and at the bottom. This will leave the woody partitions, which will prevent decay at the bottom and drying out at the top. Conservation of Cuttings. In some cases vine cuttings may be planted with success as soon as they are made. This can be done only in light, well-drained soils where there is no danger of the ground be- coming water-logged and remaining in this condition for' some time. Except in such cases it is better to defer the planting of the cuttings until most of the winter rains are over and the soil commences to warm up in the Spring. To preserve the cuttings in good condition until this time they must be kept from drying out or being injured by too much moisture. If they are buried in sand or loose soil in such a way that at least the butts are in contact with the soil they will keep well until April. The sand should be comparatively dry and well sifted in to the centers of the bundles of cuttings. These bundles should be small and if they are to remain in the sand for more than two weeks they should be loosely tied, or better still, not tied at all, but simply buried in thin layers. Unless the sand is in contact with the cuttings nearly every- where, many will dry out, and die if the sand is dry, or they will mold and decay if the sand is moist. A good place to bury the cuttings is a shed or cellar or on the north side of a building. If such a place is unobtainable they may be put in a hole at least as deep as the cuttings and covered up well with soil. Over this soil should be placed a thick bed of straw, or other material, to prevent the soil drying or becoming too warm. This last precaution \ is particularly necessary if the planting is to be delayed until late Spring", for otherwise the buds and roots may start. Cuttings which have started slightly before being planted will often grow, but they do not make the best growth. Above all, the cuttings must be protected from too much moisture. A cutting injured by being kept too wet is useless, while one kept a little too dry will give good plants if soaked in water for a day or two before being planted. Definition of Good Vine Cuttings. They should be : — 1. Taken from a healthy vine which has borne good crops, regularly. 2. Of medium size, one-third to two-thirds inch in diameter. 3. Made from bearing wood (?). 4. Well ripened, as shown by firmness of wood, light colored pith and well- formed buds.' 5. Healthy, as shown by clear, uniform color. 6. Medium jointed (length of joints varying according to variety). 7. Moist. It should be possible to squeeze out a little sap from a newly made cut. 8. Uninjured by too much moisture. The pith should not have turned black or the bark have become loose. 9. Of the length most suited to the place where they are to be planted. 10. Cut through a bud both at top and bottom.