UNIVERSITY OF CALIFORNIA AGRICULTURAL EXPERIMENT STATION. ut:ng and Grafting Heslstaat bu ™n™. Riparia is in its wild state emphatically a " riverside " grape, which in its natural condi- tion ascends into the uplands only exception- ally, when these are unusually moist and fer- tile. Under cultivation, nevertheless, it does well in good upland, but is of slower growth In view of the growing interest in the im- portant matter of rendering our vineyards proof against the attacks of the phylloxera, and of the delay in the publication of the report for 1886, in consequence of the accumulation of matter at the State printing office, an abstract of the main points discussed somewhat elabo- than in its natural habitat. It does not fre rately in the forthcoming report, is here given, quent the heavier soils as much as the alluvial in order that those contemplating the use of re- loams of the upper Mississippi valley. Itisof very sistant stocks for this season may be assisted in long-jointed, slender growth, so that its canes, their choice of varieties. while of great length and bearing abundance of The true criterion of resistants is that the foliage, are often borne by a surprisingly thin vine and its roots will not only outlive the at- trunk, which is not as easy to graft as most tacks, but flourish and bear remunerative crops, other varieties. The cuttings root with great under the same conditions under which the more ease, but general y only a portion, varying ac- sensitive European vines will succumb. cording to the soil and seasons from one-half to But every vine, like every other plant, ia sub- three-fourths, are large enough to be success- ject to certain conditions of soil, climate, and fully grafted the third year; seedlings arrive at atmosphere for its welfare. Any vine, or any about the same condition the fourth year from other plant, may be planted where from unfa- the seed. To offset these disadvantages, the vorable conditions it will not flourish, and Riparia is now usually considered the most where a slight addition to the adverse in- generally and tenaciously resistant toward the fluence8 may cause it to either die or maintain attacks of the phylloxera. It is very little only a feeble existence, useless to the cultivator j liable to mildew 2. Vitis cordifolia, the southern riverside grape, so greatly resembles the Riparia that for some time it was not distinguished as a separate species. While it is undoubtedly a yery resistant stock, the fact that it is at home in a region noted for its perpetually moist atmos- phere, seems to render it less promising ior gen- eral success in California than the Riparia, over which, so far as known, it possesses no special for profit. The resistant vines are no exception to this general rule. Adaptation of Vines to Soils. — It is not rea- sonable to suppose that a vine which is natu- rally at home in rich, heavy lowland soils, should not only flourish but supply extra strength against attack from without, in thin, meager upland?, or on land exhausted by long cultiva'ion; nor that a vine whose hardy roots resist the phylloxera when growing in its natu- (advantages, save, perhaps, in the case of * very ral location on dry, rocky uplands, will neces- 'heavy adobe soils, to which it is better adapted sarily retain this character when grown in than the Riparia. rich, moist lowland. To a certain extent, culti- 3. The litis aestivalis or summer grape is a vation does modify and equalize the natural native of the uplands of the States east of the soil-conditions, especially when it is thorough Mississippi, and is at home on loam soils of and is faithfully kept up. But there always re- good or fair fertility. It also descends into the mains a certain margin of natural adaptation lowlands of the smaller strean s, so that it and which must be respected even in the cultivated the Riparia vine are not uncommonly seen side plant, and the more because climatic and sea- by side. But it is rarely if ever found in the sonal conditions may render a strict fulfillment larger bottoms, though quite at home in the of the best culture impracticable, or unavailing lighter and usually well drained u second bot- for the time being. Those cultivating adobe toms" or " hammocks." Unlike the riverside soils will appreciate the importance which this grapes, it objects to "wet feet." It is little consideration may acquire, not only for one subject to mildew. Of the cultivated varieties but for several consecutive seasons. of the aestivalis grape, those of chief interest as Species and Varieties of Resistants .—Of the resistants are Norton's Virginia, Herbemont, American species and varieties that, for practi- and the well-known Lenoir. The cuttings of cal purposes, may be considered as resistant these, as well as the wild vine, root with some under proper conditions of soil and moisture, difficulty; they should be rooted in nursery, the following are the most prominent: and not in the vineyard itself. 1. The Vitis riparia, or northern riverside 4. Vitis mpestris, the sugar or rock grape of i-ape and its cultivated varieties, of which the Missouri, is a very hardy vine, at home on Bay lor and Clinton are the chief. The resist- rocky knolls and hillsides, where its wiry roots ant power of the latter is now, however, pretty extract nourishment from the scanty soil and generally admitted to be inferior to that of the crevices of rocks, in a climate already par- their wild prototvpe, although they are better taking somewhat of the aridity of the great adapted to a great variety of soils. The plains. It would, therefore, seem to be of con- siderable promise for the foothills of California especially; of its resistance to the phylloxera there can be no question. It is, however, not easy to root from cuttings, being in this re- spect like the aestivalis varieties. In my personal experience I have found it to be of slow growth on rich upland adobe, even more so than the Riparia, so that very few cuttings were ready for the graft the third year; moreover, even when the top of the stock is sufficiently stout for grafting, that por- tion generally tapers off very rapidly down- ward, so as to afford very little 4< grip " for the graft, which has to be tied in very thoroughly. The successful grafts, however, have shown a vigorous growth and seem well joined. The multitude of wiry suckers which the stock per eists in putting forth to the end of the season constitutes an inconvenience, shared to some extent by the Riparia, and least of all by the Californica, which soon gives up sprouting its easily detached suckers. The Rupestris is least subject to mildew of all the resistant stocks. 5. Vitis Californica, the California wild grape (not, as some still imagine, the 11 Mission " vine, which s very sensitive toward the phylloxera), has been prominently brought fcrward as a re- sistant stock for use in its native State, to the climate of which it must be presumed to be especially adapted. This reasonable presump- tion g.ves it so great a claim to attention and renders its pre- eminent success so probable, that nothing but the strongest proof of its non- lesistance should induce us to relinquish its use; but experience speaks strongly in its favor. It goes without saying that the Californica, like any other vine, may be planted in the wrong place, where its half-starved roots be- come hardened, and instead of yielding so as to render deformation from the bite of the phyl- loxera impossible, will curve and curl, and finally die and decay. The Californica is very liable to mildew, and it is probably from this cause that it is but rarely found on the coastward slope of the Coast ranges, which are much exposed to the sea fogs. There is, however, no difficulty in protecting it by repeated sulphuring, up to the time of grafting. 6. Vitis Arizonioa, the wild grapevine of Arizona and Sonora, resembles somewhat the Californica in its general appearance and habits of growth. In rapidity of growth it seems to be nearly or quite equal to the Californica, and quite its equal in resistance to the phyl- loxera, as well as to drought. It is subject to mildew nearly as much as the former. Its roots, also, seek the depths of the soil before branching, and the stock is stout and easily grafted. From experience had at the Univer- sity, it deserves more attention than has here- tofore been bestowed upon it. In none of the stocks mentioned above does tnere appear to be any intrinsic difficulty about making a sound joint with the vinifera va- rieties. But when a strong grower is grafted upon a weak one. there may be difficulty on account of the weak base of a stouter trunk. In the reverse case there is no trouble, for a relatively stout base for a weak trunk is desir- able. The strong-growing Californica will, in its own home, furnish just such a stock for all, or almost all, the vinifera varieties, which it exceeds in growth whenever planted in ap- propriate soils. In my personal experience with the Cali- fornica, I have found only one variety which seems to exceed it a little in growth when grafted, viz. : the Clairelle Blanche, which is an extraordinary grower. In the case of five other varieties grafted in my vineyard (Black Burgundy, Palomino, Mondeuse, Verdelho, Cinsaut) the graft junction is at the end of the season either straight (t. e., a cylinder), or like a wine bottle right side up, the Californica stock forming the body of the bottle, the graft the neck. There can be no doubt that in these cases the stock will push the growth of the grafted variety. Where the same varieties have been grafted on the Riparia or Rupestris stock, the case is just the reverse. Here the graft junction re- sembles a bottle placed neck doivn, and it is at least questionable that the stock will be able to supply fully the needs of the graft, and pretty certain that it will not tend to push the latter beyond what its growth would be if on its own root. In the case of the Rupestris And ClairetU the disproportion is painful to contemplate, the quill-like stock appearing absurdly inadequate to the support of the graft that has swelled to the proportion of a man's thumb. That this is felt by the stock is apparent from the frequency with which the grafts have thrown out their own roots when on either Rupestris or Riparia stock, thus defeating the primary object of grafting at all. No such tendency is seen in the same varieties where they are on the Call- fornica stock. But this, it must be remem- bered, happens on a soil peculiarly well adapted to the Californica, and on which the rupestris, at least, should not have been used at all. Experience which appears in some respects the reverse of my own, has been had hy the Briggs Bros, near Winters, in a light alluvial soil. As has been shown in a former bulletin (No. 24) the Californica appears in the uplands pref- erably on heavy, rich soils, although in the val- leys it does well on a great variety of lands. In the red gravelly uplands of the Coast Range and foothills, it should probably be replaced by some of the Aestivalis stocks, such as Lenoir or Herbemont. Rapidity of Development of the Several Re- sixtant Vines. — That in our climate the Califor- nica develops most rapidly of all, especially as to making a stock of grafting size, is hardly doubtful. The experiments made at the Uni- versity from 1881 to the present time, as well as personal experience in my vineyard at Mission San Jose, fully corroborate the claim that the Californica is a stock of extraordinary vigor on favorable soils, and will bear very early grafting. It will be remembered that in the first experiments made with the grafting of seedlings at the University, in 1881, of seedlings one year old about 40 per cent were found stout enough for grafting, and were successfully grafted; a thing not even remotely possible with any other species of vine yet tested, and least of all perhaps with the riparia, whose seedlings are ot exceedingly slow development. Thus, of a plantation of riparia seedlings located on exceedingly favorable soil on Mr. John T. Doyle's place at Cupertino, not one could have been grafted when two years old, and only a few were fairly graf table when four years old. At my own vineyard at Mission San Jose, the stocks from one-year-old Californica seedlings, planted in spring of 1884 were, without excep- tion, large enough to be grafted in spring | 1885, despite a very unfavorable season. They weie not actually grafted, however, until March and April, 1886, when, notwithstanding the extraordinarily dry season preceding, the trunks ranged in thickness from a minimum of two-thirds of an inch to fully 1£ inch, and sometimes more; eo that two grafts could read ily have been inserted in a large portion of them. Of the Riparia cuttings planted at the same time as the Californica seedlings, few ex- ceeded one-half inch in thickness, and very many were too slender to be grafted with any prospect of success, especially in view of their large pith. Of the Rupestris cuttings planted at the same time, few reached the thickness of half an inch, and many appeared no thicker than when planted, three years before, except that they had at the top a short head, like that of an old short-pruned stock, but too short to be of any use in making the graft. In this case, however, all the conditions were most favorable to the Californica stock, as ob- served on the wild vine on its own ground. As to loss or gain of time in grafting, a loss of 10 per cent of the grafts made in the field must ordinarily, I think, be considered a very favorable result; it will more frequently amount *o between 12 and 20 per cent, varying not only according to the skill of the grafters, but very largely depending upon the condition of the grafts used, and upon the weather fol- lowing the operation; also, to a not inconsider- able degree, upon the nature of the soil. The influence of the latter becomes apparent from the fact that vine-grafting must be done either several inches below the surface of the ground, or, if done at or near the surface, the soil must afterward be piled up around the graft for pro- 1 tection against drying-out. In the case of an I | adobe soil, in which the water may remain near the surface for several days after a rain, the in- trusion of muddy water into the cleft or cut, and a consequent weakness of the junction and even risk of failure to unite, may take place. Hence, as such soils in good tilth retain moisture very strongly, I incline to think that in them the grafting is best done within one or two inches of the surface, the piJing-up of the earth around the graft being relied on to prevent drying. With the same view, my personal ex- perience inclines me to favor late* rather than very early grafting, because then the free flow of sap from the stock keeps the graft in good heart. I think the average experience will be found to be that there is a loss of one year, or there- abouts, when a vineyard is grafted instead of being allowed to bear directly from the cut- tings; and that on the large scale the cases ot gain in time will be very exceptional. Propagation of the Resistant Stocks — Of the above species the riparia is the one of which the cuttings can unhesitatingly be planted di- rectly in the vineyard; the Arizonica is next; while the rest, including the Rupestris, should preferably be rooted in nursery. Probably it would also be best to graft them there. From what I have seen of the growth and habits of riparia seedlings, I should not in* cine to their use in preference to cuttings, on account of their delicacy and extremely slow development. It is quite otherwise with the Californica, of which even very small seedlings grow very readily and rapidly, and are very tenacious of life under very adverse circum- stances. Considering the advantages to be gained by grafting on vigorous resistant stocks in regions menaced by the possible importation of the phylloxera, one season's delay (which I think should be looked for by those who graft) should not deter any one from taking this needful, and with proper care as to adaptation, ultimately profitable precaution. E. W. Hilgard. Berkeley, Jan. 28, 1887. * "Late" as regards the stage of development of th leaves, but not necessarily late in the season.