CONTHIBCTION TO THE CHEMIBTPT
XXX.-cONTRIBUTION
423
OF FRUIT CULTUKE.
TO T H E CHEMISTRY O F F m I r C U L T U R E .
BY PROF.C. A. GOESSMANN. I. STRAWBERRIES.
T h e variety of strawberries which furnished t h e material for the examination, is known as the "Wilder." T h e plants turned t o accoiint for my tests, were raised upon the College grounds, upon a plat which, until two years previous, had. been used for the prodiictioii of grass. They were two years old, and in a healthy bearing condition. T h e first lot of fruit was just ripe when the investigation began. One hundred parts of the entire fresh plant, without its fruit, lost 72.26 parts of moisture, a t n ternperature of from 100' t o 110' c. One hundred parts of t h e ripe fruit lost from 89.03 to 90.31 parts of moisture, a t a temperatiu-e of from 100' t o 110' C. One hundred parts of an average specimen of our strawberry plants, befove removing any of its fruit, consisted approximately of fifty-two parts of fruit, i n all stages of development, and of forty-eight parts of roots, stems and leaves. One hnndred parts of the fresh plant, without its fruit, left, after a careful calcination, 3.34 parts of ash constituents. One hundred parts of the ripe fruit are known t o leave, according to several investigators, in t h e case of different cdtiwuted varieties, from 0.41 t o 0.63 parts of ash const.ituents. -4 careful examination of t h e ashes obtained from the fruit of the " W i l d e r " and from the remaining portion of the plants which furnidied t,he berries, carried out a t my suggestion, by Mr. E. B. Bragg, during the past year, gave t h e following analytical results. T h e sulphuric acid and the chlorine contained in these ashes have been excluded from t h e calculation presented below, for the reason that t h e amounts noticed, even in a carefully charred mass, do not represent the exact amount present in the plant, and thus cannot serve as a basis in comparative studies like ours. One hundred parts of the ashes, as speciticd previously, contained in the case of the fruits (I), and of the plants without the fruits (11):
I.
Potassium oxide.. . . . . . . . . . . . . . . . .49.24 . Sodiuni oxide.. .................... 3.23 Calcium o x i d e . . . . . . . . . . . . . . . . . . . ...13.47 Magnesium oxide. . . . . . . . . . . . . . . . . . . 8.12 Ferric oxide.. ...................... 1.74 YhoHphoric a c i d , . . . . . . . . . . . . . . . . . .18.50 . Silicic acid (soluble in soda solution). 5.66
.
11.
10.62 parts. 13.35 '' 36.ti3
''
3.83
"
14.48
'' ''
14.17
"
6.91
AS these st:ttcmcnts are most likely the first ones published regarding the mineral constituents of oiw O C o w ~)rorriiiieiitc:iiltivatcd varieties of strawl)cti.ries-thc. " \ViI(ler "-it may not h, withoiit interest to fruit-growers, i n geiieral. t o c~inipwre t l i c l above-statvtl analytical results with tliosc of : I N analysis of the ashes of t,he f i x i t of the wilt1 str;&wherry(EFtrgtrrilc .w, I,], :LS rep0rtt.d by Hic.hardson. One hiindrecl parts of the wilt1 f'riiit coritai~ied0.41 part * of ash constituents. One huritired parts of that ash, calculated on the above specified basis, containcvl : Potassiuni oxide, . . , . Sodium oxitlc . . . . . . . . . . . . . .,.14.@H E'et~ic.oxide . . . . . . . . Pliosphoric acid. . . . . . . . . . . . . . . . . . . . I 4.47 . . . . . . . . . . . . . . . . . . . . . . i 2.62
('
" "
A careful comparison of the composition of tlie ashes of No. 1 above, with that of the ashes of the wild frriit just represented, reveals remarkable differences, which deserve the serioiic; attention of the practical fruit-grower ; for it shows, in a striking manner, the pecnliai. action of these two kinds of strawberries on the soil resources of plant growth. The variations here noticeable, in regard to the relative proportiom of the mineral elements in the ash of t h e wild and the cultivated variety of strawberries, are not less remarkable than those known regarding some of their inovt prominent proximate organic uonstitiirnts, as siigai' and acid. The ordinary wild strawberry contains usiia11y one acid to t w o sugar, whilst in case of some cultivated varieties, it changes from o i i e t o six, or more. T h e question, whether the variat.ions in the relative proportions of t h e mineral elements found i n fruits, bear a n y definite relation t o their general character, can searcely be any more doiibtcd since the study of the best modes of imparting to some of our farm crops a higher valnk for apecia\ iiidtistrial application, leads quite iiaturaliy t o that conclusion. According to thiN view, it is h i t reasonable to consider it most. important to aseertain, by careful cheniird analysis, the relatioils which exist between the ehemical and physical condition of t h e soil, and the mineral constitnents of the fruits raised upon it ; for that kind of information furriishcs tlie foiiritlntjion of a rational syptein of manuring our friiit bearing plants. To produce new varieties, and t o p i d u c e the best of each kind in the largest possible quantity, are qiiest,ioiis requiring each an independent course of experimental
CONTRIBUTION TO THE CHEMISTRY OF FRUIT CULTUKE.
425
observation. It is quite certain that the practice of restoring t o the soil-in suitable form and in due time-those constituents, at least, which the fruits we gather abstract, cannot otherwise but contribute towards large crops, by stimulating a vigorom, healthy condition of the riitire plant. A strong, healthy plant is quite naturally better qualified t o overconie internal local disorders, and to resist external injurious influencw than feeble specimens. T h e extensive root system of our fruit trres tends to conceal the gradual exhaustion of the soil ; i t delays merely the failure of our orchardr. A liberal supply, in particular, of thohe ewential eleinents of plant food, which are found in the fruits in conspicuous quantitie-, and which, for obviour reasons, must serve important fiirwtiolir in their growth, if judiciously applied, cannot otherwise but p r o l e beneficial to their reproduction. To secure that ariiount itr a more defined form, i. e., by means of some chemical commercial fertilizer, than has hitherto been customary, cannot otherwise but improve most decidedly our chances to ascertain not only the special warits of the plants under cultivation, b u t to recognize also the particular form in which the various articles of plant food exert the moat beneficial iutluence on the qiiality of the fruits. I succeeded, in vonuequence of t h e liberal application of potassa and phosphoric acid, in changing the proportion of potash, and also of grape sugar, of the wild purple grape t o that of a good ripe Concord grape. A? the fertilizer applied had evidently modified, in a certain direction, both the organic and inorganic portion of the grapes under cultivation, the experiment can serve as an additional illustration, that the fertilization of fruits with reference to quality, is within our possibilities. T h e artificial feeding of fruit bearing plants, once based on rational principles, will gradually alter our current notions of severe pruning, in the interest of a larger and more valuable crop ; whilst a mo,re thorough knowledge of the exact chemical relations of different varieties of fruit, respecting their characteristic organic and inorganic constituents, may even furnish a safer basir for t h e selection of varieties most promising for the production of new valuahle varieties, in which well defined qualities may supplement each other. 11. C R A V B E R K I b : ~ ( K w c i t i i t i t t ~ mtwrocarpon, Gray). T h e sample of cranberries which furnished the material for rpy invebtigation, was obtained from a party engaged in their cultivation, who desired to know t h e relative pi-oportion of the essential articles of pldrlt fdod contailled in this fruit, ohviously for the purpose of
forniing some definite idea regarding a successful restitution of the elenleiits cwrietf off by the crops. E'iritliiig n o r t w r d ( I f any 1 ) w v i o i i s analysis of onr cnnl)eri,icca, within I I I lit(>rary ~ resouiws, I d w i t l d t o undertake thc. task of ail cx;tniiiiatiori t t ~iriect tlie rt.llucwt. .ICthe results obtained with the :L t:irlc~eIJf MI..E. 13. Ihg!J of' the ('lass of I 8 i 5 , 111;typrove of iiite t t u others, ( I I I :m*ouiito f t l w iiimmiiig iniportaiiw i n our owit State, ( J f tile growing of' rr:tiilwrries, I irsk leave to r q i o r t them. T h e ctverage s ~ ~ ~ ~ i i~ii i (~n ~n hnr si - i e s t r h t e d towards the end ( i f the tnoiitli of Octolwr, in I8i;ii ; t i i l l i i i 1 8 7 7 , aliout two weeks after they had lieeri h:wvested, (*ont;iined in one Iirintlred parts : 1876.
18iT.
Moisture a t 100' to 110' C . . . . H ! ) . z ~.. . . . . ~ g . t i S o],arts. D r y niat,ter . . . . . . . . . . . . . . . ~ ( I . ; I . . . . . . 10.110 (' A 4 constitrients i n dry niatter -. . , . , ( t . I ;!I h'itrogen i n d r y matter.. . . . . . . . . . ( I , 1 ti(I " '(
T h e juice of these berries had in tmth samples, :t sliccitie gravity eqnai t o 1.025 at 1 5 O (2. temperature. It contained i i t 1876, 1.35 per cent. of grape s,upar, and in 1 H i 7 , 1 . 7 0 p w c e u t . of that substance. No caue sugar was foulid. T h e free acid o f the juice, c&wl:tted as malic acid, amounted in the first stated instance to 2.25 pci. (wit., and in tlie S W Y J I I ~ one, to 2.43 per cent. It consisted most likely of t w o acids-citric. and malic. acids. T h e dried ash of t h e cranberries collected i i i I B i i , containcd, a f t e r deducting the carbonic acid, the eulphuric acid, and the chlorine, i n olle 11undretl pal'la : Potassium oxide. . . . . . . . . . . . . . . . . . . . . . .47.!+0 parts. Socliririi oxide. 6.58 " Calciurn oxide . . . . . . . . . IR.5X . . . . . . . . . . . . . ti.78 '* Ferric. o x i d e . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.66 " Phosphoric acid, . . . . . . . . . . . . . . . . . . . . . . . 11.27 " Silieic acid (with traces of sand) . . . . . . . 5.22 '(
66
In presenting these analytical results to the consideration of the cultivators of cranberries, I do not intend to reconinirnd to theni, as an unfailing recAeipt for the successful cultivation of that fruit, the use of a fertilizer which contains t h e above specified relative proportions of the various articles of plant food, compounded merely with ~ result reference t o the cheapness of the form. Such a C O I I ~ Rwould ultimatcly in a general disappointnient among practical farmer?, regarding the merits of analytical chemical inquiries into the relation8
C O N T K I B U ~ I O N TO THE C1IEYIBTRY OF FRUIT CULTURE.
427
of plant growth. Having, during past years, from tirne to time, published results of investigations of a similar character, it may not be o u t of place to discuss once, briefly, the question : " W h a t d o we A good learn from an ash analysis of plants like the above?" chemical analysis of a carefully prepared ash of a matured plant, is the only way by which we are enabled to ascertain with absolute certainty, the various kinds and the amount of each of the mineral elements which the plant under examination has incorporated. I t is also t h e most exact mode by which we can learn the character, and t h e degree of the loss the soil has suffered in mineral matter, in consequence of assisting in the growth of that plant. Whilst we are thus compelled, in the light of our preient informatioil, to recognize a good analysis concerning the mineral constituents of all our caltivated plants, as the first requirement for the development of a rational Rystem of manuring our farin lands, we are not less obliged to concede that we deri\e hut a part of the informatioii we need to insure a reasonable succesa under otherwise favorable oircurnstances. The more carefully we have studied during the IJaSt thirty y e ~ r s ,in t h e field, in thc vegetation house, and in the laboratory, the relations which exist Itetween the soil conditions and plant growth, the inore are we forced to recognize the correctnrss of that conclusion. T h e above stated ash analysis, like any other ash analysis of plants, gives neither any direct information regarding the particular cornbinatiun, which the various constituents form within the plant, nor does it tell in what specific form tlie plant prefers to assimilate the mineral elements from the soil ; it shows siniply, that certain elements have been noticsed in quantities m stated, without claiming to give any valuable inforination regardiiig their rniitiral relations to each other in the vegetable econoiny of tlie plant which contains thein. T o recognize merely the 1mseiic.e of different elements i l l the ash of plants, does not entitle-without any other qualitication-to the assumption that they are all of an equal iniportance, and essential for a successful growth; nor can it he asserted, with anything like certainty, that even the absolute ainoirnt of the mineral eliments found in plants, is incliRpensable for their reprodnction. T h e ash constituents of plants are known, as far as the same variety in a (*orrespondingstate of development is concerned, to differ in most instances more nr less i n reqard t o their absolute quantity as well ns the relative proportion of their essential elements. These 1 ariations are, however, found more serious in the case of ahsolrite quantity, amounting sometimes t o from fifty to one hrindred per cent. of total ~u(011
CONTRIBITTION TO ‘THE CIIF,bfISrRY OF FitUl’r CULTURE.
429
girdled branches, ripened from two t o three weeks earlier than those on tingirdled branches. T h e investigation has heen directt;d of late, mainly to an inquiry into the circumstaiices which favor the production of the best and earliest ripe grapes, without endangering the life of the vines subjected to the treatment of girdling. T h e subsequent statement of the observation of Messrs. C. S. H o w , of the Clash of 1878, and W m . G. Lee, of the Class of 1880, upon the college vineyard, contain a summary of the results thiw far seciired. In entering upon these tests, it was decided to study the subject with reference t o the following points : r , 1 he best time for girdling. W i d t h of girdle. Place of the girdle on tlie vine. Effect of girdling on the vine during the first as well as the RIICceeding seasons. One hundred and ten Concord vines, located in the same part of t h e vineyard, of southern exposure, served for the expwimeiit. They werc girdled a t intervals of one week, beginning on the 1 it11 of June, and closirig on the 25th of August. Tile girdling was carried on in ten differelit ways. The work began with ten vines, and each Rucceeding week were added ten new oiics to the experiment. Tlie most suitable time for the girdling of the Concord vine exteiids during the entire month of Jiily, varying sornewhat, according to the more or less advanced state of general growth, diir to the peculiarity of the seas0.n. T h e best results during the past season were obtained from vines girdled on the 7th of .July, and the opening kept cleared from new growth until the middle of August, when the wound m j y be allowed to grow over. T h e girdle of one-half of aii inch wide pri)ved more eficient than tliose of less dimension. 1,;trger ones are a p t not to close up before t h e growth ceases, and thus terminate the life of the Tine. Entire vines-or better, one or inore years old brniiches of vigorous plants-are best adapted for t h e pirdling process. Tlie girdled new growth produced sorite tine fruit, and much in advance of those on ungirdled new wood ; h i t tlie liability of the latter to break, renders that rnode objectionable if not wholly impracticable. T h e vigor of the vines remains appareiitly uninjiirrd by girdling. Vines girdled two and three years ago are, as a general rule, thrifty, and although the girdir ia grown over, the girdled brancli produces a marked difference in its fruit ; in some instances the latter still ripem fully a week earlier.
