UNIVERSITY OF CALIFORNIA, AGRICULTURAL EXPERIMENT STATION. BERKELEY, CAL. E. IV. HILGARD, Director. BULLETIN NO. 97. INVESTIGATION OF CALIFORNIA PRUJMES, AfRICOTS AJMD PEACHES. The subjects discussed in this paper are summarily set forth in the following quota- tion from Bulletin 93 of this department: " The purpose of this work is to show com- prehensively the proximate and ash composi- tion of the leading varieties of fruits as grown in the principal fruit regions; and inferen- tially, the influence exercised upon them by the prominent conditions of soil, climate, fer- tilizers, etc. The physical data (proportion of pits to flesh, etc.) are of interest from a com- mercial standpoint, as showing what is being purchased as to available and waste material, etc. "The consumer, though usually considering fruit as a luxury, would derive much valuable knowledge from studying the fruits in their relative values as foods. The nourishing por- tions, shown especially by the nitrogenous and saccharine contents, vary greatly with the va- riety and conditions of growth. It is not, then, a matter of indifference to the consumer what fruit he uses, but an important question of do- mestic economy. M The ash ingredients, together with the nitro- gen contents of the standard varieties, are of high interest in connection with the vital ques- tion of soil exhaustion and fertilization. The soil ingredients extracted by an ordinary crop are a serious drain upon the supporting soil, and the lines of heaviest draft can only become known by the actual determination of the con- stituents withdrawn." It will be observed that the majority of the fruits here reported are from the Santa Clara valley, from which they were most readily obtained. It of course intended to extend this work, hereafter, to all the fruits grown in California; notably, during the coming season, to all obtainable varieties of figs from the different regions; also, a more numerous representation of apricots, prunes and other plums. It is well known that these fruits differ materially in their quali- ties e. g. as between north and south Cali- fornia, and between the valley and the foot- hills. These investigations will not only aid in determining the best uses to which these several fruits may be put, but also in what direction and to what extent the soil ingredients taken from the soil by them re- quire replacement. Raisins and table grapes, as well as cherries, pears, etc., will come in their turn in succeeding years. Meanwhile, producers interested in these questions are invited to communicate with the Station in regard to the examination of their fruits. In the work here presented, as in that previously done on citrus fruits (Bulletin 93), Assistant Colby has been very efficient- ly assisted by Mr. Hubert P. Dyer, a gradu- ate student in this department E. W. HlLGAKD. Berkeley, May 31, 1892. Description of Prunes, Apricots and Peaches Received. PRUNES. No. 1, Prune d'Agen, Mountain View— 5. F. Leib grower; sample received Sept. 28, '91. Usual size, but more rounded than the other samples of the same variety, quite ripe; soft and very sweet. No. 2, Prune d'Agen, Niles— Wm. Mor- timer, grower; sample received Aug. 26, '91. Condition, good, fully ripe and very sweet. Nos. 3 to 12, San Jose— John Eock grower. All of these samples, except No. 12 were received, on September 8, '91; No. 12, St. Catherine, came Oct. 3, '91, and rep- resents a fully ripe sample; No. 11, St. Catherine, was rather green. Condition, excellent for all these samples; No. 3, French, No. 7, Hungarian, and No. 10, Datte d'Hongrie, being soft, rather juicy" and sweet; No. 7, tasted quite tart; No. 4, Wangenheim; No. 5, Robe de Sergent; No. 6, Fellenberg; No. 8, Bulgarian, and No. 9, German, were firm-fleshed and much less sweet than the other members of the series. APRICOTS. Nos. 13 to 18, Niles— James Shinn, grower; samples received during August, 1891. No. 13,Hemskirk, Aug. 3, '91, was hard and unripe. The other varieties, No. 14, Hemskirk, No. 15, Blenheim, No. 16, Royal, No. 17 Peach, and No. 18, Moor- park were in good condition, fully ripe and quite sweet. No. 19, Pringle? Tulare* grown by B. F. Moore, was received June 30, '91, and has already been reported (Agr, Expt. Stat. Rept., 1890, page 115). PEACHE8. No. 20, Orange Cling, and No. 21, Lemon Cling, samples received Sept. 25, '91, from L. C. McAfee, San Francisco. Condition only fair, as the fruit had been picked for some time. No. 20 was grown by H. M. Alexander, Anderson, Shasta Co.; No. 21 by General Bidweil, Chico. The table (p. 4-5) shows the results of the analytical work for the season 1891; the first subdivision, A, gives the physical and general proximate analyses; the second, B, the results of the analysis of the ash. Lack of time prevented us from making as ex- tended a work as was desirable upon the ash — that which has been accomplished indicates at least the general character of the ash composition. The chief points shown by the table will be better understood by a brief discussion as to similarity or difference. Proportion of Pits to Flesh. Prunes.— The range in the percentages of pits is from 3.7, in Hungarian, No. 7, to 7.5 in Robe de Sergent, No. 5; 5.5 per cent representing the general average, thus leav- ing about 17 times as much flesh as pit?. Thus the consumer finds that, on the whole, the prunes possess but little advantage over each other in regard to the proportion of pits to flesh. Apricots. — Leaving out of consideration the Pringle, No. 19, on account of its small size and relatively slight importance, the variation of pit percentages is from 4.14 (Hemskirk. No. 13) to 6.7 (peach variety No. 17), a somewhat smaller difference than was found in the prunes, viz., 3.8 to 2.5 per cent. The average pit contents is 5.8 per cent, leaving about 16 times more flesh than pits. Here again, there is but a trifling advantage in choice so far as the proportion between flesh and pits is con- cerned. For equal weights of prunes and apri- cots, whole fresh fruit, the consumer re- ceives nearly the same amount of flesh or available matter; but the apricots being some three times larger than the prunes; we have, on the average, 7 apricots as against 21 prunes to the pound avoirdupois. Peaches. — The limited results obtained prevent us from making any comparisons with the figures presented for apricots and prunes. The difference between the pits in the varieties examined is too small to be considered. Lemon Cling, No. 21, has some 33 times more flesh than pits; Orange Cling, No. 20, shows 25 times more flesh. European analyses of these fruits report figures which do not differ materially from those furnished in the above table; the av- erage pit percentages for prunes is 5.4, for apricots 5.3, and for peaches 6.1, the weights for whole fruits not being given in the analyses at. hand. Proportion of Juice to Flesh. Prunes. — A glance at the figures in the table shows that the French prune, No. 3, has the largest proportion of free juice, namely, 87 per cent, nearly seven-eights of the flesh. No. 5, Robe de Sergent, falls but slightly below with 84 per cent, or five-sixths of the flesh. The driest flesh is that of No. 11, St. Catherine (unripe sample), about one-half of it being fiber; No. 12, a later and fully ripe sample of the same name, ap- proaches closely the general average of 73 per cent, or nearly three-fourths the flesh. It is important to note that Hungarian, No. 7, while the largest fruit, has nearly ten per cent less juice than the average French prune, i. e., 70 against 80 per cent. Apricots. — The relation between juice and fiber in the flesh is quite constant, as none of the figures obtained differ more than five per cent from the general average (87.3 per cent), the juice amounting to about seven-eights of the flesh, Nos. 16, 17 and 18, respectively Royal, Peach and Moorpark varieties showing the highest proportion of juice (90 per cent), and Hemskirk, No. 13 (not fully ripe), the lowest (82.3 per cent). The average flesh of the apricots, from this showing, is apparently more juicy than that of the prunes, in the ratio of 7 to 6. Sugar Contents of the Juice, Flesh and Fruit. The work undertaken this season (1891) did not comprehend the determination of the different sugars (dextrose, levulose, cane sugar, etc.), contained in prunes and apricots; the length of time necessary to complete such an investigation for each sample required us to limit the work to the determination of the most important point — the total sugars. Prunes. — By far the highest sugar per- centages are found in the ripe, soft and juicy French prunes of the various locali- ties; the somewhat harder varieties, Wan- genheim, Robe de Sergent, Fellenberg, Bul- garian, German and Datte de Hongrie yield- ing, on the average, six per cent less sugar. Although there is a difference of one month in the picking (Sept. 28th to Aug. 26th) of the French prunes from Mountain View and San Jose, yet, for the flesh and fruit, the sugar content is nearly identical, 18.6 per cent for flesh and 17.6 per cent for the entire fruit, fresh. St. Catherine, No. 12, with 22 per cent of sugar in its j uice, com- pares well with the sugar percentage (av- erage 22.6 per cent) in the juice of French prunes; referring these figures to the flesh and fruit, those for the St. Catherine are some 2.5 per cent less on the average. In connection with the St. Catherine, it is in- teresting to note the wide difference, fully 6.5 per cent, in the sugar found in No. 11 (not fully ripe) and No. 12 (fully ripe) picked over three weeks apart. Among the other (or) firm-fleshed prunes, the widest difference in sugar percentages is 3.8; Datte de Hongrie, No. 10, showing 12.44 per cent and Wangenheim, No. 4, 8.80 per cent for the whole fruit. A sample of dried French prunes (No. 24) ready for consumption, from same crop as No. 1, Mountain View, and referred to that, yields 47.25 per cent of sugar. This latter figure is a little over four times larger than the general average of sugar in whole fruit of the fresh prunes. Apricots, — Both the early (picked in June) and later varieties (picked in August), with the exception of the (not fully ripe) Hemskirk, No. 13, show a remarkably close resemblance to each other in regard to sugar contents; the Royal, No. 16, with 15.06 per cent, and Peach, No. 17, with ANALYSES OF CALIFORNIA PRUNES, APRICOTS AND PEACHES, CROP OF 1891. A. - PROXIMATE ANALYSES. Name of variety. Number Place of production. Sender or grower. PRUNES. Date of receipt and analysis PHYSICAL ANALYSIS. Average weight, in grams, t Number per pound Flesh, per c^nt Pits, per cent FLESH. Juice, pressed, per cent Pulp, pressed, psr cent JUICE. Total sugar by copper (inversion), per cent. . . . Acid, in terms of Bulnhuric ( Sus ), per cent. . SUGAR. In fresh flesh, per cent In fiesh fruit, ptr cent NITROGEN. In whole fresh fruit, per cent In fresh flesh, per cent Id fresh pits, oer cent Albuminoids in whole fresh fruit (equivalent to nitrogen), per cent ASH (Pure). In whole fref h fruit, per cent In fresh flesh, per cent In fresh pitB, per cent GfcNERAL PROXIMATE ANALYSIS. Water, per cent Organic matter, per cent Ash, per cent Prune d'Agen. Prune d'Agen. French. Wan- gen heim. Robe de 8er- gent. Feilen- berg. Hunga- rian. Bulga- rian. Ger- mau. 1. 2. 3 4. 5. 6. 7. Moun- tain View. Niles. San Jose. San Jose. San Jose. San Jose. San Jose. San Joae. San Jose. 8. F. Leib "Wm. Morti- mer. John Rock. John Rock. John Rock. Johu Rock. • John Bock. John Rock. John Rock. Sept. 28, .891. Aug. 26, 1891. Sept. 8, 1891. Sept. 8. 1891. Sept. 8, 18yi. Sept. 8 1891. Sept. 8, 1891. Sept. 8, 1831. Sept. 8, 1691. 23.5 20.4 91.5 5 5 22.9 20.8 94.9 5.10 20 8 23. U 94.24 5.7K 19.5 24.6 95.0 5.0 20.0 24.0 92.5 7.5 26.0 18 5 94.1 5.90 80.5 6.0 96.3 3.7 25.6 1S.8 93.8 6.2 25.5 18.9 9j.3 4.7 72 6 UA 81.2 18.8 86.8 13.2 69.0 31. u 83.8 16 2 76.4 23.6 70.0 30.0 64.0 36.U U.5 28.6 25.6 .23 20.50 .24 21.73 .28 13.45 .52 14 03 .48 12.05 .59 14.04 .95 13.81 .50 12.60 .„ 18 52 1/.5U 16.60 15.60 18.87 17. b4 9.26 8.80 11.78 9.89 9.20 8.67 11.20 10.72 8.37 7.92 9.05 8.43 178 .148 .785 .145 .142 .641 .168 .124 .766 .140 .log .£88 .134 .083 .753 .139 .117 .499 .122 .114 .326 .121 .168 .118 .15j .514 .512 1.112 .906 1.050 .870 .837 .879 .762 .7561 1.050 .613 .6uU .661 .395 .387 .519 .442 434 .582 .376 .365 .629 .361 .317 .627 350 .344 .434 .392 .385 .416 .410; .370 .40J .38/ .491 .434 75.96 23.43 .61 79.650 19.955 .395 77.00 22.66 .44 79.74 19.88 .i8 82.50 17.14 .36 85.69 13.96 .35 85.50 14.11 .39 82.72 16.87 .41 83.00 16.63 1 •* 100.00 100. to 100.00 100.00 100.00 100.00 100.00 100.00 10J.OO t 30 trams are equivalent to 1 ounce. B. - ANALYSIS OF THE ASH. Percentage Composition of the Pure Ash. FRUIT. Place of Production. of Pure Asb. Potash. Soda. Lime. FRENCH PRUNES. San Jose. .442 3.18 3.u7 65.92 69.50 24.01 3.24 .434 3.01 ROYAL APRICOTS. Whole fruit Niles. .582 4.53 10.57 11.20 3.45 6.04 pita ..^^^^'.^'.'.^^^'.^ , !!.■! .550 .542 .681 54.88 £8.59 lu.95 3 52 3.24 6.75 ANALYSES OF CALIFORNIA PRUNES, APRICOTS AND PEACHES — Continued. -PROXIMATE ANALYSES. PRUNES. APRICOTS. PEACHES Datte d'Hon- grie. i St. 1 Catha- i rine. i St. Catha- rine. 10. It 12. San Jose. San Jobs. San Jose. John Rock, John Rock. John Rock. Oct 3, 1891. Sep\ 8 J 891. Oct. 3, 1891. 21.6 22 2 94. U 6.0 20.2 23.7 95.1 4.9 18.5 26.0 94.8 5.2 81.7 18.3 53.0 47.0 63.4 30 6 16.50 .38 14.32 .34 22.00 .28 13.36 12.44 8.63 8.10 15.21 14.34 .133 .104 .560 .144 .116 .751 .185 .150 .866 .842 .900 1.156 .330 .320 .405 .362 .349 .595 .44C .431 .526 81.40 18.27 .33 83.30 16.34 .36 78.78 20.78 .44 100.00 103. CO 100.00 Heins- kirk. NiJes. James Shinn. Aug 3, 1891. 89 3 5.1 95.86 4.14 82.3 17.7 7.0 6.8 Hems- kirk. 14. Niles. James Shinn. Aug 14, 1891. 63.0 7.1 93.98 14.2* 13.43 .84 11.54 10.70 .199 .168 .784 .530 .512 84.77 14.70 .530 Blen- ! helm. 15. Niles James Shinn. Royal. 16. Nilts. Peach. 17. Niles. Aug. 3, 1891. James James Shinn. j Shi un. Aug. 7, Aug. 14, .891. ! 1891. 57.5 ! 7.8 93.30 i 6.70 90tt) 10.0 15.72 .58 13.84 12.50 .133 1.O50 1.150 .454 .440 .533 85.50 14.05 .45 Moor- park. Niles. Priu- gle? 19. Or- I Lena- arge on Oiing Cling AVERAGES. Apri- Prunes. cots. An- der- Tulare, sou. Chico Dried Prunes. Prune d'Agen. 24. Moun- tain View. 81.0 46.8 5.6 9.6 94.75 93.40 5.25 6.60 85 3 90.3 14.7 9.7 13.43 15.06 .46 11.61 13.56 11.03 12.30 .242 .258 .210 .217 .880 .840 1.513 1.610 .555 .550 .540 .542 .850 .681 84.600 85.11 14.845 14.34 .555 .55 IH.M. Gen'l James B. F. (Alex- Bid- | Shinn. j Moore, janderj well.! S. F. Lelb Aug. 19, June 6, Sept. ! Sept. ! 1891. i 1891. 25, '91 25, "91 1391. I 59.2 ; 24.8 153.5 215.5 7.6 18.0 ! 3.1 2.2 94.0 9J.90 93.9 93.7 6.0 1 9.10 6.1 ; 6.3 90.0 10.0 13.58 .64 79.1 ! 20.9 76.2 23.8 13 50 20.0 14.00 ; .17 .32 loo.oo loo.oo ; loo.oo 100.00 12.10 ! : 16.00 10.80 11.30 1 15.00, 10.00, .2c9i. .224 . .8u5 . 1.619 . .494 . .484 .612 85.90 13.61 i .49 : 78.5C 86.50 j 2J.88 13.06; .62 .44 100.00 100.00 100. 00 100.00 27.1 66 1 10.0 20.5 7 3 48.0 94.55 94 2 9J.0 5.45 5 8 10.0 73.3 87 3 2d. 7 12 7 16.70 13 31 .43 63 !«2 47.25 12.30 11 F6 11.65 10 76 .148 221' .122 m .628 871 .92S 1 427 3.00 1.65 .403 m .395 504 .526 703 81.29 85 57 28.00 18 31 I 13 91 70.35 .40 52 1.65 100.00 1 100.00 100.00 B. — ANALYSIS OF THE ASH. Composition of the Pure Ash. Magnesia. Peroxide of Iron. Br. Oxide of Manganese. Phosphoric Acid. Sulphuric Acid. Silica. Chlorine. Total. Less excess of Oxygen, due to Chlorine. Total. 6.16 .85 .31 13.19 2.37 4.56 - .19 99.97 .05 . 99.92 5.33 .83 .17 11.56 2 13 4.30 .20 100.10 .05 100.05 16.26 1.14 1.90 32.98 5.40 7.88 .22 100.16 .05 100.11 3.85 1.71 .21 13.86 2.95 7.85 .60 1C0.00 .15 99.85 3.31 .77 .09 11.20 2.75 8.31 .58 100.04 .14 99.90 11.58 12.39 1.65 43.76 5.38 2.58 1.65 100.14 ,40 99.74 5 15.72, the highest in sugar, showing but about 2 per cent more than the general av- erage, 13.34 per cent, for the juice. Taking the general averages of sugar in the juice of prunes and apricots (columns 22 and 23), we find that the prunes stand a trifle over 3 per cent the higher; for the flesh, and for the whole fruit, the difference is considerably less, viz., about one per cent. Apricots, then, according to these determinations, range much lower in sugar (six per cent) than the Prune d'Agen, the difference being nearly the same as already noted above for the harder prunes. European reports of these fruits show that the juice of prunes, on the average, contains 6.15 per cent sugar, apricots 4.69 per cent (one case is reported of a small va- riety of apricots with 16.5 per cent sugar), and for peaches 4.48 per cent, these figures being from 2.5 to 3 times less than those herein presented for these fruits as grown in central California. There seems thus to be good cause for the preference they have 9b quickly attained in the market. By reference to the small table following the relations to each other of the average sugar and acid contents of some California fruits will readily be seen. For convenience of comparison the acid is expressed in terms of sulphuric acid (S0 3 ). JUICK. FLKSH. i WHOLE FRUIT. Acid, per Sugar, Per Cent. cent. Apricots from Niles .63 13.34 11.56 10 76 Prunes from Niles, Sau Jose and Mt. View- .43 16.70 12.30 11.65 French prunes, do. do.. .25 22.60 18.33 16.91 Grapes from various lo- cal I lies .60 24.00 23.00 20.70 Oranges from various localities 1.34 9.65 6.20 4.70 Peaches from Ander- son, Shasta Co., and Chico .24 17.00 13.40 12.50 Acid in the Juice. Prunes. — The maximum, nearly one per cent, js at once seen in the Hungarian, No. 10; the minimum, .23 per cent, in the Prune d'Agen, No. 1; the average, .43 per cent, be- ing almost twice the minimum. Apricots. — While the acids differ from .50 per cent to .80 per cent, they do not show as great a diversity as the prunes in this re- spect. In both fruits it appears that low acids are combined with high sugars. Eu- ropean analyses, which report the acid in terms of Malic, when corrected for Sul- phuric, give for prunes .51 per cent, apri- cots .70 per cent and peaches .55 per cent, which do not differ much, except for peaches, from those we report. Nutritive Values— Nitrogen Contents. The flesh-forming ingredients of any article of food being of great importance as regards its proper uses (see Bulletin 93 of the department, relating to oranges and lemons) it is of special interest to compare in this respect the prune and apricot to other fruits, and the different varieties of prunes and apricots amongst themselves. As heretofore set forth in Bulletin 93, the Cal- ifornia orange with 1.20 per cent albu- minoids, while lower in these ingredients than the Sicilian (albuminoids 1.73 percent) was rated the first in this respect amongst our fruits. la so far as our later work bears in this direction we must accord to the apricot (edible portion alone) an equal place, albuminoids being 1.19 per cent; the prune (.76 albuminoids) takes the second place, leaving the other fruits, grapes, bananas, apples and pears (from European data) to stand in the order now mentioned till we find opportunity to study them. The apricot as a whole (pits included) shows 1.43 per cent albuminoids, or .23 per cent more than the orange. Among the prunes the highest percent- ages of albuminoids (.94) is found in the flesh of German, No. 9, and the ripe St. Catherine, No. 12, closely followed by that of the prune d'Agen with ,86 per cent; the lowest of the series being the Robe de Ser- gent, No. 5 with only .52 per cent — about .2 per cent less than the average for the flesh of all the prunes, which is .76 per cent. The flesh of the apricots shows even a greater difference in albuminoids than the flesh of the prunes, being quite one-half of one per cent; the maximum, 1.37 per cent albuminoids is seen in the Royal, No. 16 and the Moorpark, No. 18; the minimum, .84 per cent, in the peach variety, No. 17, 7 ranges nearly with the highest albuminoid content in the prunes (.94 per cent). Apricots grown in Europe average .49 per cent albuminoids, just about one-third as much as the Californian (1.37). European prunes (with .78 per cent albuminoids), however, are more nearly like the Califor- nian ( 76 per cent) in this respect. With this portion of our work we give below a summary of the food constituents of some of our dried (cured) commercial French prunes, dried apricots and grapes: 7^ Dried. Edible portion. 7 tO 5. Zi > in g first), among fruits in the quantity of mineral master withdrawn from the soil, we find that, weight for weight, the apricot has the second place; and that the prune and the orange have about an equal right to the third place, thus again bringing plainly be- fore us the fact that we cannot safely use European results, as heretofore, as a basis of comparison for our fruits. Upon the basis of fche preceding table of this publication and those given in Bulletin 93, we have prepared the following tabular view of the amounts, in pounds, of soil in- gredients extracted by the different fruit crops, that will have to be replaced by fer- tilization: 5£; P Water, per cent Ash, per cent Albuminoids (Crude Pro tein), per cent Crude Fiber, per cent.. Nitrogen — free Extract, per cent Fat, per cent Sugar, per cent Free Acid, Calculated as Sulphuric (8O3 ), per cent Tannin, per cent 25.20 32 44 34.83 33.00 1.3S 1.16 1.40 5 V 1.50 2.70 29.67 40"53 .40 327 31.81 2.94 3.70 170 8.30 2.17! 21.60 .56 ^9.59 52.50 32.00 1.51 .85'; 2.00 1.29| Total | 100.00100.00 100.00 100.00 *Dried and ground by R. Napa Co., Cai. K. Wood, Rutherford, The above results, while inadequate as a basis for general conclusions as to the rela- tive food values of these fruits, nevertheless indicate plainly that the nutrients, notably the sugar and crude protein (albuminoids) differ very widely, e. g. the sugar in the grape food is 20 per cent more thaa that of either the apricot or apple, and 12 per cent more than that in the French prune. Again, the crude protein %i the dried apricot is double that of the dried apple, and but one-half a per cent higher than that in the prune and grape. As to ash, we note but little dif- ference. Ash Composition and Nitrogen Con- tents. Contrary to statements in our previous publications (Bulletins 88 and 93 of this de- partment), in which, according to European data, the orange stands second (grapes be- FBUITS. Total Ash lbs. Potash lbs. Phos. acid lbs. Nitrogen lbs. GRAPES. «| 1 1 Europ ean. In each 1000 lbs 8.8 5.00 1.52 1.70 APRICOTS. European. In each 1000 lbs 490 86 Crop of 30,000 lbs.... California. 147.00 25.80 .71 In each 1000 lbs 6.16 2.16 2.29 Crop of 30,000 lbs. ... 15480 84 98 21.38 68 70 PRUNES. European. 3.73 .95 In each If 00 lbs ..... 6.3 1 22 Crop of 30,000 lbs.... 189.00 111 90 28.53 36 60 California. In each 1000 lbs 4.03 2 6.53 .53 1.48 Crop of 30 000 lbs .... 120 90 79.70 15.95 44 40 ORANGES. European. .07 In each 1000 lbs 6.07 2.78 j 2.69 Crop of 20.000 lbs.... 121.40 55.60 13.40 53.80 California. In each 1000 lbs \ 432 211 .53 1.83 | 86.40 42.20 10 60 36.60 California prunes thus appear to draw much less upon all the mineral ingredients which have to be replaced by fertilization than the European; the latter, however, draw much more lightly than the former upon nitrogen. Apricots both of California and Europeaa growth stand, in total amount, about equal as to mineral ingredi- ents withdrawn; as to nitrogen, the Califor- nia fruit draws 2.5 as much, showing the very material difference in the relative pro- portions of the vital soil ingredients among themselves. Potash. — In the ashes of prunes and apri- cots, as in the orange, potash is seen to be the leading ingredient (at least one- half the ash), ranging somewhat higher in the for- mer two fruits. In its distribution as be- tween pits and flesh, the greatest difference 8 is shown by the European prune; for apri- cots we have no foreign data. Although potash constitutes so large a portion of the ash of these fruits, its replenishment to the soil will be delayed long beyond the addi- tion of other fertilizing ingredients, because most California soils are naturally so well stocked with it that available potash for the current demand will, iu many cases be ade- quately supplied for many years. Phosphoric Add is not so heavily drawn upon, nor do our fruits in any case, so far, quite reach the same demand upon the soil in this respect as the European. Its distribu- tion between pits and flesh, also, is not quite so variable as that of potash. Since our soils usually contain a limited supply of phosphoric acid, the prune and apricot as well as the orange orchards will require phosphatic fertilizers first, when any are used. Nitrogen. — The apricot here leads in its demand upon the soil in this substance, closely following the European orange. Averaging the nitrogen withdrawn by the prune and apricot, we obtain a figure but slightly greater than that for the orange; emphasizing for those fruits the same necessity of early replacement of nitrogen, and partly for the same reason; viz., that California soils are usually not rich in their natural supply of this substance. Of the other ash ingredients, it will ;be seen that lime is quite constant, although much less in amount (for prunes) than Eu- ropean standards show. Especially is this difference seen in the comparison of the ash analyses of the flesh and pits. In the orange ash the lime content far exceeds that of either the prune or apricot; accord- ingly, as our soils generally contain plenty of lime, even for oranges, we would rarely expect to fertilize with a view to its replace- ment. Soda is seen to be much higher here than in European analyses of the a8h of the prune; this is probably explained by the fact that California soils, like those of other arid regions, contain much more soda than the European. Geo. E. Colby. ANNOUNCEMENT. The Board of Regents of the University has granted Director Hilgard a leave of absence for one year from June 15, 1892, and has appointed E. J. Wickson Acting-Director during the same period. In this connection, attention is again called to our former request that all letters relating to experimental work, or questions of any kind, should be addressed " Director of the Station" as such, and not to individuals, as has been very generally done heretofore. 41