Hntt (HoUegc of Jlgticultute Kt OJorncU IttiucraUH artlfata. 5f. if. Cornell University Library S 639.D99 on the effect of various ferWrzer^^^^^^^^ 3 1924 003 370 933 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924003370933 A MINOR THESIS Presented to the Faculty of Cornell University in Partial fulfillment of the work proscribed for the DEGHEE OF MASTEE OF SCIENCE IN AGEIGDLTURE September 1, 1912. ON THE EFFECT OF VARIOUS FEBTILIZEES ON SOME WELL KNOWN YAM. CROPS By Oliver Wesley Dynes, B.S. FOHEffOHD The yearly fertilizer bill of the American farmer reaches in- to an amazing total. The best estimates give as the value of farm (1) fertilizers for one year the sum of $114,844,000. One half of this is expended on the farms of the South Atlantic States. The states of Georgia and the two Garolinas are the heaviest contribu- tors to this fund. One fourth of the total amount is used in the states bordering the North Atlantic seaboard. The amount used by the middle western and far western states is relatively small al- though of late years the use of fertilizers has greatly increased due largely to the propaganda carried on by a few meat packing firms in an effort to find an outlet for the by-products of their factories. The use of commercial fertilizers is essentially a soil pro- blem and has been considered such in the multitudinous fertilizer experiments carried on by the federal and state experiment sta- tions in this country. It is still a mooted question, "Can the fertility of our agricultural soils be permanently maintained (2) without the addition of a mineral fertilizer?" Y/hitney asserts (3) that this is possible while Hopkins insists that the assuinption is absurd. The preponderance of scientific evidence supports the latter theory. A careful study of the classic experiments of seventy years (4) standing at Eothamstead England and the work done in our own (5) (6) (7) country at Pennsylvania, Ohio and Illinois show clearly that a judicious use of coranercial fertilizers tends to maintain and build up the fertility of any given soil. The recuperative power of a soil, however, is often underestimated or ignored. A field at Rothomstead was allowed to go back to grass and \7eeds for tvrenty years and during that time had accumulated nitrogen at the rate of 44 pounds per acre each year. (4) -(page 139). A CROP STUDY The following study of the effect of various fertilizers is a crop not a soil study. The direct effedt of the three essential elements, nitrogen, potash and phosphorus on a few well known farm crops was observed. In no sense of the word is it a treatise on rotations or the effect of rotations on yields. Cumulative ef- fects of fertilizers were not considered. It was essentially a one year study. THE CROPS STUDIED Five well known crops were examined; wheat, oats, corn, potatoes and hay. Wheat and oats are non-cultivated general field crops. Corn and potatoes are both cultivated crops, but potatoes unlike com is capable of more intense culture and is es- sentially a truck garden crop. Hay is a perennial and requires little or no attention after it is once sown. All five are fairly representative of the large list of northern grown American field crops. SOURCES OF INFORMATION The data comprising the following tables were compiled from the publications of the state and federal experiment stations. Both the annual reports and the regular bulletins were freely drawn on. In all cases the original report of the fertilizer trial was used. In the majority of instances the experiment was conducted on the grounds of the station or sub-station. Some of the trials, however, notably, those from Connecticut are cooper- ative experiments with first-class farmers. In every case, how- ever, the experiment has been under the trained eye of an expert. METHODS OF COMPILING DATA The following points were kept in mind in selecting typi- cal fertilizer trials for compilation - 1 - Check or comparison plots were essential. Surprising as It may seem scores of fertilizer trials were disregarded be- cause check plots were lacking. 2 - Only first year data was obtained. No yields were ac- cepted that showed the ciunulative effect of fertilizers. 3 - Any trial in which standard fertilizers were not used was ignored. Sodium nitrate was the carrier of nitrogen, po- tassium chloride, potash, and acid phosphateof phosphorus. No ready mixed fertilizer was allowed. Barnyard manure was not con- sidered in any of the trials. 4 - In every case possible the previous history of the ground was noted and the nature of the soil determined. 5 - Original data on each trial was used. Suranariea of a series of trials were not considered. Plots either one-tenth or one-twentieth acre size were almost invariably chosen. DISTRIBUTIOM OF FEBTILIZER TRIALS The following series of tables are compiled from data gather- ed in 32 states and representing 315 separate experiments. Table 1 shows the location by states and distribution by crops. A limited number of trials are shown Sor oats and hay. 54 tests of wheat « 58 of potatoes and 161 of corn completes the list* The number of experiments from Connecticut, especially with corn, is very strik- ing. Many of these were cooperative trials with farmers and were very carefully planned and executed. The earliest of the Connecticut experiments were the first fertilizer trials in this country and were planned by Professor Samuel Johnson in 1877-8. It is a significant fact that a great many of the trials carried on later by experimenters in other states were identical in many respects with the early Connecti- cut experiments. This had the effect of causing less chance for error in figuring fertilizer values. Tables 2, 3, 4, and 5 give the average yield per acre of the five crops in a sunmary by states. Eight plots are repre- sented in each table. The check plot received no fertilizer. H. received nitrogen only, K. potash only, P. phosphorus, KK. nitro- gen and potash, UP. nitrogen and phosphorus, KP, potash and phos- EH 8 (M ti) o ■P ^ <:i< CD 03 a •H 01 tH o ^. W CO +3 +J 0) to 'O f:< a ^ cd o r-t rj >S ra (h CO i ^ f^ li-^ I-! o -p o o P- to to « rH W ^ w to rH 01 rH rH CD fl U •H •r-\ rH ^ >. 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THE NUMBER OF STATES DTVOLVED IN ALL OF THE FERTILIZER TRIALS. Fertilizer iheat Oats Corn Potatoes Hay Check 14 9 20 21 9 N 12 6 16 10 6 P 13 7 19 16 _ K 14 7 19 16 _ NP 8 3 10 9 . NK 8 4 8 11 KP 9 5 15 15 _ NKP 9 5 14 15 5 phorus and KKP. received all three elements or what is known as a oon5)lete fertilizer. Many of the states are not represented in the complete series. Others have an insufficient number of trials and show more or less irregularity in the yields. Com is esti- mated as shelled in all of the trials. It v;as thought best to use only the figures for the nitrogen plots and the complete fertilizer plots for hay owing to lack or sufficient data. In tables 6 and 7 is given a resume of the number of states involved in the trials and the number of trials with each crop. The checks represent the total number of experiments studied. Table 8 gives the average prodxiction per acre of all fer- tilizer trials under consideration. TABLE 7. THE ITOMBEB OF FERTILISER En^EEIMmTS STUDIED WITH EACH CEOP. Fertlliirer vmeat Oats Corn Potatoes Hay Check 54 14 161 58 28 K 43 7 108 22 12 P 45 9 136 37 . K 52 9 131 39 MP 19 3 88 21 _ KK 17 4 82 25 EP 23 6 118 46 MP 33 9 118 40 18 It can te seen readily that where a larger mamber of plots are represented in one fertilizer series than in another an ele- ment of error is introduced. Comparing the nitrogen series in wheat con5)iled from those states where the yield of wheat is in- variably low with the potash series where the wheat yields are ^o-mal is manifestly unfair. To eliminate this source of error each of the seven fertilizer plots was compared directly with its check plot. Tables 9. 10, 11, 12 and 13 furnish a compari- son with the check plots. All calculations showing the in- crease by means of fertilizers and when estimating the value of the increase were made in this way. TABLE 8. AVERAGE PRODUGTIOH PER ACRE OF ALL FERTILIZER TRIALS miDER GOKSIDERATION. Fertilizer YOieat Oats Com Potatoes Hay Brs. Bus. Bus. Bus. Ibs. ^^ Oheok 16.44 38.09 51.56 91.88 2401 IJ 16.86 42.84 37.76 85.01 3315 K 17.26 41.72 33.87 121.98 — P 19.61 41.22 35.31 107.69 HK 18.34 29.89 40.97 112.64 KP 20.43 34.04 41.96 112.03 KP 18.93 30.34 35.99 132.05 __ KKP 20.74 49.61 43.05 163.01 4205 IKFLUBt^GE OF NITROGEK Oorn and hay showed the greatest increase from the use of nitrogen. The iniluence exerted on the yield of corn is especi- ally noteworthy. In combination with either of the two minerals it seemed more effective than when used alone. Its influence on wheat and oats was not especially striking while on potatoes it seemed in some of the trials to be a positive injury. The greater availability of a nitrogen fertilizer gives it an ad- vantage over the slower acting potash and phosphorus carriers in any first year trial. TABLE 9. A GOMPAEISOIT WITH OHBDK PLOTS IN THE FEETILIZEH TRIALS Y.ITH WHEAT. No. of Trials Fertilizer Yield Per Acre Bus. Increase Value of Increase 43 Check) N ) 15.65 16.86 1.21 Ill.lO 45 Check) K ) 15.43 17.26 1.83 1.66 52 Check) P ) 16.41 19.61 3.20 2.91 19 Check) NK ) 15.06 18.34 3.28 2.98 17 Check) HP ) 15.05 20.44 5.39 4.90 23 Check) KP ) 15.16 18.95 3.79 3.45 33 Check) NKP ) 14.62 20.74 6.12 5.57 TABLE 10. A COMPAEISON WITH CHECK PLOTS IN THE FERTILIZER TRIALS V/ITH OATS. No. of Yield Bus. Value of Trials Fertilizer Per Acre Increase Increase 7 Check) N ) 38. 4S 42.84 4.42 #1.87 9 Check) K ) 37.15 41.72 4.57 1.93 9 Check) P ) 38.04 41.22 3.18 1.34 3 Check) NK ) 24.94 29.89 4.95 2.09 4 Check) HP ) 27.08 34.04 6.96 2,94 6 Check) KP ) 27.02 30.34 3.32 1.40 9 Check) NKP ) 41.24 49.61 8.37 3.54 TABLE 11. A COMPAEISON WITH CHEOK PLOTS IK THE: FERTILIZER TRIALS WITH CORK. Ko. of Trials Fertilizer Bus. Per Acre Bus. Increase Value of Increase 108 Check) N ) 34.30 37.76 3.46 vl.95 136 Check) K ) 31.66 33.87 2.21 1.24 131 Check) P ') 32.41 35.31 2.90 1.63 68 Cheek) M. ) 32.16 40.97 af.81 4.96 82 Check) HP ) 31.38 41.96 10.58 5.96 118 Check) KP ) 30.36 35.99 5.63 3.17 118 Check) NKP ) 32.12 43.05 10.93 6.16 TABLE 12. A COMPAEISON V/ITH CHECK PLOTS IK FERTILIZER TRIALS WITH PO^'ATOES. No. of Trials Fertilizer Bub. Per Acre Bua. Increase Value of Increase 22 Check) N ) 76.08 85.01 8.93 $5.77 37 Check) K ) 93.87 121.98 28.11 18.15 39 Check) P ) 81.44 107.69 26.25 16.95 21 Check) UK ) 83.25 112.64 29.39 18.98 25 Check) KP ) 77.09 112.03 34.94 22.56 46 Check) KP ) 83.00 132.05 49.05 31.67 40 Check) MP ) 93.63 163.01 69.38 44.81 TABLE 13. A OOMPAEISOK WITH CHECK PLOTS IK THE FEETILIZER TRIALS WITH HAY. Ko. of Trials Fertilizer Lbs. Per Acre Lbs. Increase Value of Increase 12 Check) K ) 2450 3315 865 $5.03 18 Chedk) NKP ) 2258 4205 1947 11.33 INFLUENCE OF POTASH As was to be expected potash proved to be the premier fer- tilizer for potatoes. The potash plots gave over three times more increase than that of nitrogen. With wheat, oats and corn the yields were seriously effected when a combination of phosphorus and potash was used. Table 12, on the other hand shows the op- posite effect. The HK plots here have an average very little greater than either potash or phosphorus alone. IFFLUEUCE OF PHOSPHORUS mieat was the outstanding crop effected by the addition of phosphate fertilizer. The yield of oats was considerably lower where phosphorus was applied than in the nitrate and potash plots. A combination of nitrogen and phosphorus gave an increase of 6.96 bushels while a similar combination of potash and phosphorus gave £03 increase of 3.32 bushels per acre, less than half as much. Table 11 shows the same results with com. Potatoes seems to be the only crop of the four studied where a combination of potash and phosphorus was not detrimental when compared to the increase from the other fertilizers. THE CABBIERS OF ITITROGEK, POTASH AHD PHOSPHORUS Nitrate of soda (Na N03) , sodium nitrate or Chile salt- peter, was the commercial form of nitrogen fertilizer used in the trials. Muriate of potash (Kcl) was the carrier of potash. Dis- solved roclc phosphate or acid phosphate which contains about 14 per cent, of phosphoric acid was the standard fertilizer in the application of phosphorus. In table 14 is given the commercial form, the amount per acre, the cost per ton and the cost per acre of the fertilizers used in the 315 trials with wheat, oats, corn, potatoes and hay. AMOUMT OF FEF.TILIZER PEH ACRE Owing to the remarlcable influence exerted by Professor Samuel Johnson in Connecticut a very large number of the trials under consideration had the same amounts of fertilizer given in the accompanying table. All trials showing amounts used greatly in excess of this schedule or those running under it were omitted in the calculation. TABLE 14. KINDS AND APPROXIMATE AMOUNTS OP FKETILIZERS PER ACHE USED IN 315 TRIALS WITH V.TffiAT, OATS, CORN, POTATOES AND HAY. Amount Commercial Per Acre Cost Cost Fertilizer Form in lbs. Per Ton Per Acre N Nitrate of soda 160 •¥60.00 #4.80 K Muriate of potash 160 45.00 3.60 P Acid Phos- phate i' ■ 320 15.00 2.40 m 160 160 8.40 Nf 160 320 7.20 KP 160 320 6.00 HKP 160 160 320 10.80 In figuring cost of the increase where so many trials were involved it was manifestly impossihle to use anything but a con- stant for the amount of fertilizers applied as well as the cost per ton, COST PEE TOK In charging any crop with the cost of an application of fer- tilizer, labor in applying it to the land should be figured in as well as the cash price paid for the actual ingredients. No at- tempt is made to get at the actual cost in cents of hauling, mix- ing and applying Imt the cost affixed is high enough to include incidental expenses of the farmer who uses fertilizers. Sodium nitrate at |60.00 a ton is higher than when the bulk of the trials were being conducted but no higher than present prices of ferti- lizers would warrant. VALUE OF INCREASE In estimating the value of the increase the average farm prices for the five years 1907-11 were taken. Potatoes were worth 64.58 cents; corn, 56.32 cents; wheat, 90.98 cents; oats, (8) 42.28 cents, and hay $11.64 a ton. These values are used in the calculations in tables 9-13. MET PROFITS PER ACBE Without exception the average yield of each crop has been increased by the use of a single fertilizing element and by the addition of any two of the three forms as well as the coxnplete fertilizer itself. Of greater importance, hov;ever, than yield is the answer to the question "Does it p^?" Only a series of years would properly answer that question but even granting that the application of mineral fertilizers is necessary for the mainte- nance of soil fertility,! an assertion not yet conclusively proven^, it is very important for the farmer to icnow whether he can expect inriediate returns from his outlay or depend on the cumulative ef- fect of his applications of fertilizdrs on future crops. Table 15 answers the question for the first year. A perusal of the table clearly shows that with the exception of potatoes and hay ferti- lizers do not act as a quick investment. The gain columns are blank with the exception of the phosphorus plot in wheat. Here a gain of 51 cents per acre is registered. The losses on oats are particularly severe. The gain column marked potatoes is the one striking feature of the table. Even nitrogen was a paying investment and where complete fertilizer was used the greatest profit was reached. One of the experimenters stated, "the lar- (9) ger the application of fertilizer the larger the yield". This fact is generally taken advantage of by truck farmers in the Long Island region of New York where 1000 pounds of fertilizer per acre Is not at all unusual. The use of nitrogen on hay shows a slight gain and it is to be regretted that more data is not available on this very important subject. This crop was at a slight disadvantage com- pared with the other four as the fertilizer was applied to the in EH CO n O o w p EH g O O Eh m (D o +5 -P O Ah ;h o o £0' -p 5 to to o ^^ rt •H Oi a CO IQ O 1-^ r^ ■U i-i 'J} m m o ■rA fl •H S M CO O 1^ rt •H '5 m [0 o lA •H cd J-i (B N fH r-H •H M ■P o fn © (D ,0 ^ o 02 W w U5 Pi CO o 1-4 I iQ to U3 m C\2 C\2 '^ o iO CO o 'T' in w to in m CO c\3 1X3 ^i §! & ei TABLE 16. CORN YIELDS IN FERTILIZER TRIALS ON CLAY SOILS COMPARED WITH YIELDS ON SANDY SOILS. CLAY SOIL SANDY SOIL Fertilizer No. Of Trials Bus. Per Acre No. of Trials Bus. Per Acre Check 54 30.56 38 27.97 N 31 31.71 29 37.30 K 40 30.58 35 31.73 P 37 32.29 36 31.21 NK 33 37.83 27 46.93 NP 29 37.66 27 43.21 KP 43 3y.88 35 34.49 HKP 39 40.81 30 - 44.60 surface of the ground and was not incorporated directly into the soil. YIELDS ON CLAY AND SANDY SOILS The type of soil was carefully described in most of the fer- tilizer trials. In the corn experiments 54 were selected as being conducted on a clay soil while 38 were carried on in a soil con- sidered sandy. Clay soils are not necessary fertile nor sandy land unproductive but a conaparison of the relative influence of fertilizers on the types of soil was desired. Table 16 shows the average yields for corn and table 17 shows the same thing for po- tatoes. Owing to the small number of trials involved in potatoes TABLE 17. POTATO YIELDS IN FEETILIZER TRIALS OK CLAY SOIL COMPARED WITH YIELDS OH SAHDY SOILS. CLAY SOIL SAHDY SOIL Fertilizer Ho. Of Trials Bus. Per Acre Ho. Of Trials Bus. Per Acre Check 15 73.73 17 84.37 K 7 79.55 4 59.95 K 8 99.20 10 106.65 P 11 78,49 9 97.71 UK 7 120.26 4 49.62 HP 9 96.49 4 81.90 KP 12 120.83 13 103.12 MP 11 138.63 12 135.35 the yields fluctuate. The yields of corn on the lighter soil respond somevAiat better to the application of fertilizer than those on the heavy soil. Tables 18 and 19 show a direct comparison of both crops with checks. Table 20 brings this out more clearly with re- spect to corn. The sand column gives a substantial increase over clay with the exception of both the phosphorus plots which are in favor of clay. Yi/hy this should be so is not altogether clear and only a more intimate study of each of the soils in- volved would answer the question. TABLE 18. A COMPARISOI'I Y;ITH CIIECK plots T.'ITH COM ON CLAY SOILS AND SANDY SOILS. CLAY SOIL SANDY SOIL Fertilizer Bus. Per Acre No. of Trials Bus. Per Acre No. of Trials Chec'-O N ) 29.05 31.71 23 31.41 37.30 29 Check) K ) 28.70 30.58 14 28.37 31.73 35 Check) P ) 27.36 32.29 17 28.56 31.21 36 Check) NK ) 31.70 37.83 21 32.13 46.93 27 Check) NP ) 28.97 37.66 25 32.13 43.21 27 Check) KP ) 30.75 39.88 11 28.88 34.49 35 Check) NKP ) 28.80 40.81 15 31.30 44.60 30 TABLE 19. A COMPARISON WITH CHECK PLOTS riTH POTATOES ON CLAY SOILS AND SAmn SOILS. CLAY SOILS SANDY SOILS Fertilizer Bus. Per Acre No. Of Trials Bus. Per Acre No. of Trials Check) N ) 71.01 79.55 7 37.34 59.95 7 Check) K ) 73.36 99.20 8 79.73 106.65 10 Check) P ) 70.52 78.49 11 80.79 97.91 9 Check) NK ) 71.01 120.26 7 37.34 49.62 4 Check) HP ) 66.09 96.49 9 37.34 81.90 4 Check) KP ) 76.53 120.23 12 79.17 103.12 13 Check) NKP ) 75.21 138.63 11 75.07 135.35 12 TABLE 20. A COMPARISOIT OF THE INFLUENCE OF VARIOUS FERTILIZERS OVER CHECKS ON CLAY SOILS AND SANDY SOILS IN YIELDS OF CORN. CLAY SAND Bus. Bus. Difference Difference Increase Increase in favor in favor Fertilizer Over Checks Over Checlcs of Clay of Sand N 2.66 5.89 3.23 K 1.88 3.36 „ 1.48 P 4,93 2.65 2.28 m 6.13 14.80 8.67 NP 8.69 11.08 2.39 KP 9.13 5.61 3,52 NKP 12.01 13.30 — . 1.29 A similar situation exists with the two types of soils upon which potatoes were grown. Where potash was applied a large increase Is noted on the clay soils although the number of trials was too small to allow a correct comparison on the NK plots. The complete fertilizer plot shows an increase in favor of clay. CORN ON GRASS LAND Out of ■;he 161 trials with corn 39 of them were on grass land. The yields on these plots are compared with the yields on all the corn trials in tables 22 and 23. It must be remembered the totals for the grass land plots are included in the averages TABLE 21. A COMPAEISOIT OF THE INHiUEUCE OF VARIOUS FEETILIZEES OVER CHECKS ON CLAY SOILS AND SAHDY SOILS IN YIELDS OF POTATOES. CLAY SAND Bub. Bus. Difference Difference Increase Increase in favor in favor Fertilizer Over Gheclcs Over Checks of Clay of Sstnd N 8.54 22.61 14.07 K 25.84 26.92 1.08 P 7.87 16.92 9.05 NK 49.25 12.28 36.97 NP 30.40 44.56 14.16 KP 43.70 23,95 19.75 ITCP 63.42 60.28 3.14 aa<~ for all the corn plots. This, of course, would have a tendency to raise the general average of plot yields and lower the amount of increas©. The difference is shov/n in the last column of table 22 and is rather striking. All of the yields of corn on the grass plots were substantially higher than the general average. COMMENTS OF EXPERIMENTERS Cornell Bul» 4-53-57 - I.P.Roberts. "No results in the corn crop can be traced to the use of fertilizers." TABLE 22.. A GOilPARISON OF THE AVERAGE YIELDS CF COM PLAITTED ON GRASS LAOT) WITH THE AVERAGE YIELDS OF ALL OORN TRIALS. GRASS LAUD ALL CQRU TRI.aLS Difference No. of Bus. No. of Bus. in favor of Fertilizer Trials Per Acre Trials Per Acre Grass Land CheclE 39 36.90 161 31.56 5.34 N 33 42.04 108 37.76 4.28 K 34 39.53 136 33.87 5.66 P 33 39.34 131 35.31 4.03 HK 33 45.14 88 40.97 4.17 NP 31 46.05 82 41.96 4.09 KP 35 45.18 118 35.99 9.19 HKP 34 47.40 118 43.05 4.35 Ohio Bui. -Vol.4, No. 8 - Page 179. "These statistics indicate that the wheat crops of Ohio have been slightly increased by the use of cormercial fertiliz- ers, but it appears that the average cost of this increase has eriualled its market value." "A dollar expended in fertilizers has produced approxi- mately one bushel of wheat." Georgia Bui. 14 - Page 74, "Nitrogen is the most effective element as a fertiliz- er for oats on this land." TABLE 23. A GOHPAEISON WITH CHECKS OF CORN GBO?:N ON GEASS LAITD WITH COHK OK ALL THE FERTILIZER PLOTS, SRASS LAinP Bus. Bus, Increase Difference No. of Bus. Increase over checks in favor Fertilizer Trials Per Acre Over Checks in all trials of Grass Check) N ) 33 37.01 41.38 4.37 3.46 .91 Check) K ) 34 35.31 37.34 1.03 2.21 -1.18 Check) P ) 33 37.01 37.10 ,09 2.90 -2.81 Check) m ) 33 35.83 45,21 9.38 8.81 .57 Check) NP 31 34,83 47.85 1Z.02 10.58 2.44 Check) KP ) 35 35.01 44.96 9.95 5.63 4.32 Check) HKP" ) 34 34.65 48,44 13.79 10.93 2.86 Indiana Bui. 34 - Page 67. "The results obtained thus far do not encourage the use of fertilizers or manures for oats on ground whose natural fer- tility will produce in a favorable year 50 to 55 bushels of corn per acre." Georgia Bui. 23 - Page 74-78. "Gonmercial fertilizers at present prices are not pr4- fitable on the soil covered by the experiment, when planted in com." Maryland Bui. 46 - Page 53. "The average results of three years' experiments in fertilizing com would indicate that it is not profitable to apply fertilizer to this crop on our soil." Horth Carolina Bui. 65 - Page 45. "The addition of fertilizers did not increase the yield to a basis approaching a paying one." SUMMAEY 1. Nitrogen was the most effective fertilizing element in increasing the yields of com and hay. 2. Phosphorus influenced the yield of v;heat more de- cidedly than either nitrogen or potash. 3. Potash was by far the most effective fertilizing constituent with potatoes. 4. Each single fertilizer and every combination of fertiliz- ers increased the yield of all five crops studied. 5. With the exception of phosphorus applications to the wheat crop^ fertilizers on wheat, oats and corn did not pay the first year. 6. All fertilizers paid a handsome return with potatoes. The greater the amount of fertilizer the larger the yield so far as the results of these experiments go. 7. Nitrogen fertilizer applied to the hay crop gave a small margin of profit. 8. Sandy soils responded more readily to fertilizers than clay soils when growing a crop of com. 9. A noticeable increase in the yields of corn was ob- tained in the fertilizer trials when grown on grass land. BIBLIOGBAFHY 1. 1910 U. S. Census Reports 2. Bulletin 22. Bureau of Soils. 3. Soil Fertility and Permanent Agriculture. C.G.Hopfeins. 4. The Book of the Eothamated Experiment. A.D.Hall. 5. Pennsylvania hulletin 90. 5. Ohio Bulletins 182, 183 and 184. 7. Illinois Bulletin 123. 8. Year Book for 1911. 9. Bulletin 65, Horth Carolina - Page 37.