f^l' d vi ■■"'^^i.', i-^- 4 t- * ' »' "^^ X/3 MVL U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF PLANT INDUSTRY- BULLETIN NO. 218. K. T. GALLOWAY, Chief of Bureau. CROSSBREEDma CORN BY C. P. HARTLEY, ERNEST B. BROWN, C. H. KYLE, AND L. L. ZOOK, Office of Corn Investigations. Issued February 17, 1912. WASHINGTON: GOVERNMENT PRINTING OFFICE." 1912. U. S. DEPARTMENT OE AGRICULTURE. BUREAU OF PLANT INDUSTRY^BULLETIN NO. 218. B. T. GALLOWAY, Chief of Bureau. CROSSBREEDma CORN. BY C. p. HARTLEY, ERNEST B. BROWN, C. H. KYLE, AND L. L. ZOOK, Office of Corn Investigations. Issued February 17, 1912. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1912. BUREAU OF PLANT INDUSTRY. Chief of Bureau, Beverly T. Galloway. Assistant Chief of Bureau, Wiluam A. Taylor. Editor, J. E. Rockwell. Chief Clerk, James E. Jones. Corn Investigations. scientific staff. C. p. Hartley, Physiologist in charge. Ernest B. Brown and C. II. Kyle. Assistant Physiologists. L. L. Zook, J. G. Willier,and Fred D. Richey, Scientific Assistants. 218 2 LETTI^R OF TRANSMITTAL. U. S. Department of Agriculture, Bureau of Plant Industry, Office of the Chief, Washington, D. C, August I4, 1911. Sir: I have the honor to transmit herewith and to recommend for pubUcation as Bulletm No. 218 of the series of this Bureau a paper by C. P. Hartley, Ernest B. Brown, C. H. Kyle, and L. L. Zook, entitled "Crossbreeding Corn." This article presents one feature of the work of the Office of Corn Investigations on the project of finding and developing higher yielding strains of corn for different geographical sections of the United States. The success that is being attained along this line is due to the utilization of the effects of acclimatization, adaptation, crossbreeding, and selection. The results of field tests in four States are given in detail. In this report the results are assembled in a manner to show the rela- tive productiveness of first -generation crosses and their parent varieties. While these results include a part of the data that are being assembled to show the effects on corn of acclimatization and adaptation, only such mention is here made of these influences as will prevent their effects being attributed to crossbreeding. These investigations assist m determining what varieties and what combinations of varieties can be most profitably grown in different localities. They also assist in revealing the qualities of seed corn that influence its productivity. Knowledge of this nature is espe- cially needed at this time to assist in establishmg successful methods of corn improvement embracing the good effects of selecting fine- appearing ears and of crossbreeding, without leading practical corn growers mto the belief that prize-winnmg eare are necessarily profit- able seed ears or that a well-selected and well-adapted variety is usually less productive than its first-generation cross. The results presented here are the first results of a series of tests being conducted with many varieties under various environments. More work more accurately conducted is necessary before general conclusions of a positive nature are warranted, but the urgent need of facts concerning our most widely grown and most valuable crop makes it advisable to publish in detail these results, which are at once of both local and general value. Respectfully, B. T. Galloway, Chief of Bureau. Hon. James Wilson, Secretary of Agriculture, 21s 3 CONTENTS Page. Introduction 7 Tests in Maryland 9 Work of 1909 9 Clioice of varieties 9 Crossing the varieties 11 Growing pure-bred seed for comparison 11 Work of 1910 11 Location of tests 11 Order of planting the test'rowff. 11 Equality of conditions for growth and productiveness 12 Presentation of results in Maryland 12 Field records in detail 12 Comparative productiveness of seed of 1908 and 1909 15 Crosses compared in productiveness with the male parent 16 Combined results of the four Maryland tests 16 Advantageous crosses 18 Disadvantageous crosses 19 Comparison of first-generation crosses with the 1908 seed of both parents . 21 Relative grain production of parent varieties and first-generation crosses - - 21 Stover weights of parents and crosses compared 23 Corn crosses at Chico, Cal. , 1910 24 Conditions of the test 24 Comparison of crosses with parent varieties 27 Relation of adaptation and yield of parent varieties to the behavior of the crosses 28 Tests in Texas 30 Work of 1909 30 Work of 1910 32 Test at Sherman, Tex 32 Test at Waco, Tex - 33 Test at Corsicana, Tex •- 34 The three Texas tests considered collectively 35 The productivity of the parent varieties and its influence upon the productivity of the crosses 37 Tests at Statesboro, Ga 42 Varieties used in the experiments 42 Aldrich Perfection 42 Cocke Prolific 42 Marlboro Prolific 42 Mosby Prolific r 43 Native of Statesboro 43 Rodgers WTiite Dent 43 Sanders Prolific 43 218 5 6 CONTENTS. Tests at Statesboro, Ga. — Continued. Varieties used in the experiments — Continued. Page. Station Yellow 43 Tindal 44 Whelchel 44 Williamson 44 Work of 1909 45 Character of the soil 45 Culture 46 Harvest 46 Work of 1910 46 Vitality of seed tested before planting 46 Plan of testing productiveness in 1910 47 Conditions for growth 49 Manner of harvesting 49 Moisture in grain harvested 49 Presentation of results in Georgia 50 Data collected at harvest 50 Some crosses superior to either parent 61 Relation of the producti\'ity of the crosses to the productivity of the pure strains 62 Adaptation as a factor in the production of higher jaelds through crossing 62 Influence of seasonal differences 63 Inferences drawn from the foregoing data 63 General consideration of all the tests 64 Indications of intermediacy 64 Percentage of moisture in shelled grain of crosses and parent varieties 65 Unreliability of averages for specific instances 65 Index 69 ILLUSTRATION. Page. Fig. 1. Diagram showing the relative production of parent varieties of com and their first-generation crosses in Maryland, 1910 22 218 B. P. I.— 668. CROSSBREnDING CORN. INTRODUCTION. In the United States corn has become the leading and most uni- versally grown crop, perhaps more because of its natural adaptability and productiveness than because of any improvement of the plant intentionally accomplished by man. Human efforts have doubtless had a great influence upon the evolution of maize, and it has been modified so as better to meet human needs. These changes, how- ever, have come about probably more because of the interdependent relations that have existed between man and corn than through knowledge intentionally applied. The evolutionary steps that have developed the maize plant as it exists to-day are so little understood that they are of little value in indicating methods to be adopted or avoided in further improving this crop. Such improvement may rest upon a close study of the effects upon the plant of different methods of breeding and a correct application of the principles evolved. The success of the work of the Office of Corn Investigations in originating and improving high-yielding strains of corn for different sections of the United States has been due to the utilization of the effects of acclimatization, crossbreedmg, and selection. Of these three factors crossbreeding is the principal one here under considera- tion; but as these as well as other factors — such as seasonal and soil conditions — usually operate together in influencing plant growth, the effects of all factors that can not be elimmated must receive consideration whenever comparisons are made. Because crossbreeding of corn is so readily accomplished, and the results are so varied and interesting, and because crossbreedmg is so generally recognized as a very important process in plant improve- ment, the corn investigations of the Department of Agriculture during 1900 and for several years following consisted very largely in crossbreeding all types obtainable. Of the first-generation crosses tested some were unusually productive, some good, some indifferent, 218 7 8 CROSSBREEDING CORN. and some unusually poor producers. The indifferent and poor-pro- ducing crosses were discarded and selection work started with the unusually productive ones. As the work progressed some decreased in productiveness while others retained their high-yielding qualities, and a few have come mto general culture as the best grain-producing strains of certain localities. As most of these crosses when tested in various localities were found to be seldom superior to local strains, the improvement of local strains by selection or by crossbreedmg and selection coni- bined became a more prominent feature of the corn work. Tliis feature has proved highly satisfactory and profitable to practical farmers, and much experimental evidence has been obtained to demonstrate that strains can be greatly increased in productiveness by centgener selection. Investigations and observations have indicated a number of lines for the improvement of general practices in seed-corn production. In this coimection attention is called to the follo\ving points regardmg corn: (1) That self-fertiHzation reduces productiveness; (2) that constant isolation, especially when unaccompanied by judicious selection, may result in the multiplication of undesirable individu- als and the augmentation of their undesirable characters; (3) that the emphasis which has unfortunately been placed upon the possi- bihty of improvmg productiveness by planting fine-appearing, prize- winning ears has reacted against the improvement of jdelds through the selection of seed from high-yielding individuals; (4) that the adaptation of the floral parts of maize to facihtate crossbreeding has played an important part in its evolution, perhaps assisting in gi^^ng it greater vigor, productiveness, adaptability, and freedom from disease than other cereals. One or more of these features has reduced yields m so many instances where increased yields were expected that some, and espe- cially those who have not witnessed improvement by selection, have become skeptical regarding possibility of increasing yields by selec- tion and desirous of tryuig radically different methods. Crossbred seed frequently gives .better yields than either parent, especially if one or both parents are i)oor producers as a result of self-fertihzation, inl)reeding, or lack of atlai)tati()n or acclimatization. Smce crossbred seed corn frequently yields less than one and some- times less than either of the i)!ir(Mi( varieties, it would be very unwise to advise the general planting of crossbred seed mthout first demonstrating what varieties should be crossed in different localities to produce seed of higher yielding ])Ower than that of the best existuig strains. The profits that may result from following 218 TESTS IN MARYLAND. 9 reliable methods and tlie losses that may result from following erroneous methods along these lines are tremendous because of the great extent to which corn is grown. As acclimatization, crossbreeding, and selection have proved effi- cient in increasing the productiveness of corn, the question of practi- cal importance is a determination of the best combination of these influencing factors. All these factors necessaril}' have a strong bear- ing upon the results presented in this j)aper. These results are pre- sented here, however, with especial reference to the comparative I)roductiveness of first-generation crosses and their parent varieties. In a future bulletin the results in these tests attributable to the efi'ects of acclimatization and adaptation will be combined with results of other work and treated with especial reference to these factors and their mfluence upon yield. TESTS IN MARYLAND. WORK OF 1909. CHOICE OF VARIETIES. In order to make the tests of as much practical value as possible, varieties grown by successful corn growers in Maryland and adjoining States were chosen. Composite samples shelled from a hundred or more ears were used in order to equalize results of mdividual ear variations. Detailed information regarding the history and description of these varieties is given in Table I, together with the germinating power of each lot of seed, both in the spring of 1909 and of 1910. 12305°— Bui. 218—12 2 10 CROSSBREEDING CORN. g g to o ^ c "Si O C e I a o n ■< 218 TESTS IN MARYLAND. 11 CROSSING THE VARIETIES. Selection 119, which has been undergoing improvement for 10 years by tlie ear-to-row method of breecHng and adaptation to con- ditions of the Potomac River soils near Washington, was chosen as the male parent, and the crossed seed was obtained by planting one of the other varieties in every third row in a field of this variety located 3 miles south of Washington, D. C, on a small tributary of the Potomac. As soon as the tassels appeared they were removed from all the varieties, so that no pollen matured in the field except on the rows of Selection 119, which fertilized the silks of all the other varieties, forming the supply of crossed seed, the productiveness of which was compared in 1910 with pure seed of the parents. About 30 of the best ears from these detasseled rows were chosen as seed for these tests. These ears were shelled, making a composite sample of each crossj which was used in planting all of the tests. A supply of the original seed of all the varieties used in making these crosses was retained in the seed-corn room of the Department of Agriculture according to the best known methods of seed preservation. GROWING PURE-BRED SEED FOR COMPARISON. In order that the tests of productiveness might not be restricted to the old seed of the parent varieties, isolated plats of eight of the varieties, including the male parent — Selection 119 — were grown in 1909 from the original seed. These 1909 plats were grown in the same localities and under the same conditions as the original seed. WORK OF 1910. LOCATION OP TESTS. Duplicate tests of productiveness were made at Derwood and at Pike Crossing, Md. Derwood is located about 16 miles northwest of Washington, where the soil is of a red-clay, flint-stone nature, and the two tests were located on similar soil. Pike Crossing is situated about 5 miles north of Washington, where the soil is of a mica, red-clay nature. At Pike Crossing the two tests adjoined, but the first test was located on land that had been in sod for some 10 years or more, while the duplicate test was located on impoverished soil that had grown truck crops for fully as many years. At these points the season of 1910 was unusually dry and unfavorable for com. ORDER OF PLANTING THE TEST ROWS. In order to have the means of comparing the productiveness of the crossed seed grown in 1909 with seed of the parents grown the same season and with the original seed of the parents used in making the crosses, the plantings were made in the order shown in Table II. 218 12 CROSSBREEDING CORN. It will be seen that by this order the original or 1908 seed of the two parent varieties is planted on either side of the crossed seed, and that adjoining these two rows is a row from the seed of each parent groA\Ti in 1909. In all four of the tests the varieties were planted in the same relative order. EQUALITY OF CONDITIONS FOR GROWTH AND PRODUCTIVENESS. Care was taken to so locate the rows that those to be compared would have equal facihties for growth and productiveness. At each location and for each test rows of uniform width were marked off both ways. Five kernels were planted in each hiU and the stand thinned to two stalks to the hill. Practically a perfect stand of plants was obtained for each row of each test. Each variety and first-generation cross was thus represented by the same number of plants, occupying the same number of square feet of adjacent, appar- ently similar, soil. PRESENTATION OF RESULTS IN MARYLAND. FIELD RECORDS IN DETAIL. Table II presents full details of both the original and the duplicate test at Derwood and of like tests at Pike Crossing. The order of occurrence of the varieties in the table is the same as in the test plats. Table II. — Tests of ■parent varieties and first-generation crosses of corn. At Derwood, Md. i First test. Duplicate tesi ,. Yield. Yield. w 6 Variety and cross. "3 fe . Num )er of u Number of 'A o o a ears. «»4 O o 3 ears. ^ fe cfl Ph u * "S £ £ 3 T3 § O p o B 3 ■6 8 o 1 2 02 Lbs. P.cl. Lbs. Lbs. P.ct. Lbs. in Selwtion 110, 1909 100 ,')3 3,5 4,5 52 100 70 6,5 28 65 11 Selection lo9, 1909 100 53 40 51 47 98 66 60 ;« 60 12 Selection l.sg, original . 100 64 4,5 59 51 100 71 60 36 61 13 Selection l.jOX Selec- tion 119 100 100 56 60 - 3 20 40 71 56 61 61 102 99 71 66 1 60 65 41 31 60 14 Selection 119, original. 63 IS Selection 119, 1909 100 63 50 45 59 100 71 63 34 61 16 Selection 137, 1909 100 58 3.5 56 67 98 60 55 37 66 17 Selection 137, original. 97 56 40 43 62 100 63 60 37 61 18 Selection 137X Selec- tion 119 101 100 67 56 8 40 45 60 43 67 62 100 98 75 64 6 65 50 33 45 72 19 Selection 119, original. 64 20 Selection 119, 1909 99 61 3a 57 59 100 70 65 29 60 21 Selection 138, 1909.... 100 47 26 59 71 100 51 45 42 74 22 Selection 138, original. 100 47 20 70 66 99 60 50 45 68 23 Selection 13SX Selec- tion 119 100 100 .58 60 - 9 50 30 54 62 74 61 100 99 68 55 0 60 4,5 38 41 69 24 Selection 119, original. 59 25 Selection 119, 1909 100 67 57 39 57 100 66 5.5 43 55 218 Length of row 164 feet. TESTS IN MARYLAND. 18 Table II. — Test of parent varieties and first-generation crosses of corn — Continued. At Derwood, Md.— Continued. Variety and cross. First test. JO ■3 ^ Yield. C3 la Number of ears. o o O o o Duplicate test. ■3 Yield. W si Number of ears. o o Selection 119X Selec- tion 119 Selection 119. ori^'inal. Whitecap, original Whitecap X Selection 119 Selection 119, original. Selection 119, 1909 Ohio Learning, orig- inal Ohio Leamiug X Se- lection 119 Selection 119, original. Selection 119, 1909 Illinois Learning, orig- inal Illinois LeamingXSe- lection 119 Selection 119, original. Selection 119, 1909 Reid Yellow Dent, original Reid Yellow DentX Selection 119 Selection 119, original. Selection 119, 1909 Sturges Hybrid Flint, original Sturges Hyljrid Flint X Selection 119 Selection 119, original. Selection 119, 1909 Silvermine, original... SUvermineX Selection 119 Selection 119, 1909 Golden Eagle, original Golden Eagle X Selec- tion 119 Selection 119, 1909 Fraley Yellow Dent, original Fraley Yellow DentX Selection 119 Selection 119, 1909 Selection 77, 1909 Selection 77, original.. Selection 77 X Selec- tion 119 Selection 119, 1909 Red Blaze, original. .. Red BlazeX Selection 119 Selection 119, 1909 Cross 100, 1909 Cross 100, original Cross lOOX Selection 119 Selection 119, 1909 Cross 120, 1909 Cross 120, original Cross 120X Selection 119 Selection 119, 1909 Hickory King, orig- inal 100 99 100 100 100 100 100 100 100 98 100 99 99 99 99 101 100 100 99 100 100 100 98 100 98 100 100 98 100 100 100 100 100 97 100 100 99 100 100 101 100 99 100 100 100 Lhs. 60 58 49 .58 54 GO 46 56 56 56 46 58 48 61 50 61 .'iO 69 34 58 60 62 50 57 66 43 60 63 59 59 55 53 48 55 61 46 59 69 53 44 51 49 55 57 62 56 51 P.ct. -10 -13 - 1 - 6 ■11 -11 - 7 - 5 - 9 -14 18 60 20 35 30 54 50 26 35 32 25 41 59 35 46 47 45 45 50 22 62 40 40 25 20 43 25 35 45 45 43 35 30 30 25 40 55 43 75 45 40 30 35 50 37 29 40 04 74 63 70 60 47 63 70 65 64 52 55 63 48 46 56 49 51 76 45 62 57 62 77 52 75 64 53 54 63 61 66 65 70 45 37 52 2.5 48 55 65 61 46 60 Rj 60 51 Lbs. 51 54 49 55 53 49 27 35 53 53 35 47 52 58 39 50 61 62 33 49 69 60 37 47 64 30 45 62 64 56 55 48 47 48 57 34 45 57 58 48 51 48 49 49 52 52 101 100 100 100 99 100 100 100 97 100 101 100 100 100 101 99 99 101 106 100 99 99 101 100 98 100 100 101 99 100 99 100 101 97 100 100 98 100 99 100 98 100 100 99 99 98 100 Lhs. 66 70 53 72 63 70 50 74 69 56 46 55 54 02 49 60 56 55 30 44 134 44 41 54 69 45 57 58 59 60 62 59 64 58 63 51 65 61 47 41 60 59 63 61 74 58 60 P.ct. - 3 17 -11 -10 - 7 27 50 60 40 60 55 60 50 70 50 65 50 45 45 60 56 60 50 55 40 40 20 30 33 47 50 48 45 52 55 50 54 55 55 40 50 70 65 50 50 40 60 45 74 45 57 45 60 45 34 54 39 39 36 33 30 47 39 38 52 54 39 29 43 52 39 52 56 60 64 43 40 47 41 55 43 40 42 45 42 55 48 28 36 48 43 45 45 53 25 50 45 47 29 Lhs. 1 Unrelial)le, as this row occupied the dead furrow. 218 14 CROSSBREEDING CORN. Table II. — Tests of parent varieties and first-generation crosses oj corn — Continued. At Deewood, Md. — Continued. Variety and cross. First test. Duplicate test. "3 Yield. 3 w 0 .0 i Yield. d ^ M ft Number of ears. OJ > B Id (— 1 Number of ears. ■a § 0 8 0 0 0 u 0 0 Ph 1 73 rriekory King X Selec- tion 119 101 100 100 99 99 100 Lbs. 63 62 55 58 58 60 P.ct. 7 - 5 52 30 35 35 20 38 50 74 62 77 80 64 Lbs. 79 59 50 48 56 60 100 99 99 99 99 99 74 64 58 70 70 70 p. a. 21 4 77 48 54 60 60 50 24 47 41 37 41 47 Lbs. 83 74 75 76 77 Selection 119, 1909.... Selection 78, 1909 Selection 78, original.. Selection 78 X Selec- tion 119 59 51 55 67 78 Selection 119, 1909.... 65 At Pike Crossing, Md.i 34 35 36 37 38 39 40 Selection 159, original. Selection 159X Selec- tion 119 Selection 119, original. Selection 119, 1909 Selection 137, original. Selection 137X Selec- tion 119 Selection 119, original. Selection 119, 1909 Selection 138, original. Selection 138X Selec- tion 119 Selection 119, original. Selection 119, 1909 Selection 119X Selec- tion 119 Selection 119, original. Whitccap, original — Whitecap X Selection 119 Selection 119, original. Selection 119, 1909 Ohio Learning, orig- inal Ohio Learning X Selec- tion 119 Selection 119, original. Selection 119. 1909... Illinois Learning, orig- inal Illinois Lt>amingX Se- lection 119 Selection 119, original. Selection 119, 1909 Reid Yellow Dent, original Reid Yellow Dent X Selection 119 Selection 119, original. Selection 119, 1909 Sturges Hybrid Flint, original Sturges Hybrid Flint X Selection 119 Selection 119, original. Selection 119, 1909 Silvermine, original... SilvermineX Selection 119 Selection 119, original. Selection 119, 1909 I 218 By mistake this row was cut. 82 80 79 81 82 78 82 76 85 79 86 80 80 80 84 85 83 81 83 80 81 78 83 79 81 80 82 82 82 85 82 82 83 77 86 79 82 40 48 50 42 50 44 48 36 55 42 47 44 43 39 48 47 53 36 45 54 54 43 47 52 53 36 49 51 52 32 49 49 47 32 40 50 53 -20 16 -12 -16 -12 - 7 -20 32 47 51 32 47 40 48 29 54 36 45 43 39 40 43 44 47 31 48 48 50 51 52 52 52 38 54 44 47 44 56 55 36 20 33 44 48 42 32 24 36 32 34 30 38 27 35 36 31 37 26 33 34 32 48 29 28 29 28 22 24 24 36 24 32 28 33 20 21 39 52 37 32 31 39 39 40 40 46 45 42 48 61 48 46 42 43 42 49 45 50 25 34 48 50 33 50 47 57 32 45 49 54 27 41 45 49 46 39 48 52 73 79 82 82 79 76 86 82 80 82 80 77 76 79 77 81 79 82 81 80 81 80 82 82 81 79 78 81 81 81 81 82 80 77 73 82 79 81 16 11 10 11 5i 6 n lOi ■li 5t 7| 11 7 8J 4 5 6i 14i 8 9 \2\ 13i 9i 15 6i 12} 12} 20 19 21 24i 14i 14i 7 8J -44 -49 -45 -61 -36 -44 -27 -15 -12 46 46 39 50 27 30 39 51 24 25 33 48 33 38 21 26 36 51 43 46 49 54 41 43 41 59 38 59 48 65 0 36 10 50 2 54 4 57 0 55 0 58 0 32 0 40 > Length of row 135 feet. TESTS IN MARYLAND. 15 Table II. — Tests of parent varieties and first-generation crosses of corn — Continued. At Pike Crossing, Md.— Continued. First test. Duplicate test. Yield. Yield. « 6 Variety and crosB. "3 W5 u V ^ Num ber of Number of o °t ears. "o ears; is 0; Si m 03 W 5« > o r/3 i ►J ^1 <:! 2 ■6 o o O o o o o C § PL, > 3 M Lba. P.ct. LU. Lhs. p.ct. Lbs. 41 Golden Eacle, original. 74 26 20 4^ 25 81 2\ 0 20 21 42 Golden Eagle X Selec- tion 119 78 74 45 45 - 8 26 40 46 28 36 45 84 80 7* -21 0 0 39 34 32 43 Selection 119, original. 43 44 Selection 119. 1909 78 45 44 28 46 80 s-i 0 39 46 45 Fraley Yellow Dent, original 79 50 48 27 53 82 5 0 29 46 46 Fraley Yellow DentX Selection 119 77 44 -10 40 25 53 84 9^ 12 1 44 54 47 Selection 119, original. 79 50 47 28 55 181 «* 0 44 49 48 Selection 119, 1909 77 53 48 23 58 81 12 0 58 51 49 Selection 77, original.. 77 48 40 32 50 82 6^ 0 40 42 50 Selection 77 X Selec- tion 119 71 78 46 52 -13 41 40 21 34 48 56 82 »81 8 8 -20 0 0 44 42 48 .51 Selection 119, original. 52 52 Selection 119, 1909 79 53 44 29 59 82 ^ 0 42 49 53 Red Blaze, original. . . 79 44 52 20 44 81 6 0 37 29 54 Red BlazeXSelection 119 73 78 48 55 - 9 52 48 18 24 45 54 81 182 7^ lOi -20 0 1 42 50 44 55 Selection 119, original. 48 56 Selection 119, 1909 73 52 52 16 58 82 12i 1 51 48 57 Cross 100, original 80 40 40 24 49 82 4* 2 16 44 58 Cross 100 X Selection 119 : 71 72 48 52 -14 48 52 17 17 50 50 81 182 10 16i -31 4 4 35 45 55 59 Selection 119, original. 50 60 Selection 119, 1909.... 82 60 52 24 51 82 IS 5 45 57 61 Cross 120, original 65 43 38 24 48 81 m 10 36 44 62 Cross 120 X Selection 119 77 82 58 53 12 60 45 12 38 57 47 82 182 20h 15i 22 10 6 42 46 56 63 Selection 119, original. 53 64 Selection 119, 1909 80 44 36 37 51 80 17 6 39 53 65 Hickory King, orig- inal 68 35 44 20 56 80 18 12 45 47 66 Hickory KingX Se- lection 119 . . (0 75 49 42 10 58 28 14 37 51 51 83 180 16.V 6 6 3 40 49 54 67 Selection 119, original. 50 68 Selection 119, 1909 80 45 36 40 48 80 m 0 33 48 69 Selection 78, original.. 77 33 24 39 33 83 9V 0 34 36 70 Selection 78 X Selec- tion 119 82 80 42 37 2 32 20 38 46 36 46 81 181 Hi 12 11 4 1 41 41 42 71 Selection 119, original. 45 72 Selection 119, 1909.... 81 37 23 43 46 79 15 6 39 41 1 1909 seed substituted for original seed. Table II shows the usual inexplicable variations of test-plat work. Especially do such variations occur in the duplicate planting at Pike Crossing where the soil was so deplete of humus that from a fuiancial standpoint the crop was a failure. Under these very adverse con- ditions it is rather surprising that the results accord with those of the other three tests as well as they do. COMPARATIVE PRODUCTIVENESS OP SEEDS OP 1908 AND 1909. Table II shows 42 instances in which the 1908 seed and 1909 seed of the male parent were planted in adjacent rows. In 33 of these 42 instances the 1909 seed produced the better, in five the 1908 218 16 CROSSBREEDING CORISr. seed produced the better, and in four the yield was the same. The 1908 seed produced 1,797 pounds of ears and the 1909 seed produced 1,938 pounds, a decreased yield of 7 per cent, due, perhaps, to the poor development or loss of A^igor of the 1908 seed. The 1909 seed was groA\ii from the 1908 seed under conditions that prevented any crossing with other varieties. Its greater productiveness therefore can not be attributed to mixture with other varieties. While the 1908 seed of Selection 119 produced 7 per cent less than its progeny seed grown in 1909, it is not certain that the age of the 1908 seed was the cause of the decreased productiveness as the seed germinated perfectly the spring following its maturity, and also showed a germination of 98 per cent in the spring of 1910. The 1909 seed showed a germination of 100 per cent in the spring of 1910. A comparison of the productiveness of the 1908 and 1909 seed of the female parents shows sufficient instances in which the 1908 seed produced better than the 1909 seed to make the average production of the 1908 seed equal to that of the 1909 seed. CROSSES COMPARED IN PRODUCTIVENESS WITH THE MALE PARENT. In computing the per cent of increased 3'ield over the male parent in Table II the seed of the male parent grown the same 3'ear the cross- ing was accomplished is considered. As none of the female parents consistently produced better than the male parent, the male parent of all the crosses. Selection 119, is taken as the basis with which to compare the crosses. In all cases the average yield of two rows, the nearest one on either side of the cross, is compared with the cross. Considering that contradictory results from any of the four tests is sufficient cause for ignoring all four of the tests, we have remain- ing five crosses which produced uniformly less than their male parent, and two comparisons in which the cross uniformly produced better than either parent. The five first-generation crosses (x Selection 119) that uniformly produced less than the better of the two parents are Illinois Lea- rning, Sturges Hybrid Flint, Silvermine, Golden Eagle, and Selec- tion 77. The two firstr-generation crosses (X Selection 119) that uniformly produced better than either parent are Cross 120 and Hickory King. COMBINED RESULTS OP THE FOUR MARYLAND TESTS. In Table III the four separate Maryland tests are combined. In the Derwood test some of the female-parent varieties were represented by both 1908 and 1909 seed. In such instances the average of the two has been used. In these combined results this comparison of the crosses with the ]>etter yielding of the two parents is a straight comparison of the crosses with their male parent, for it is more pro- 218 TESTS IN MARYLAND. 17 ductive than any of the female parents except Fraley Yellow Dent, which it equals. Table III. — Productiveness of first-generalion crosses of com compared uith that of the better parent, 1909 seed of the male parent being considered. Variety and cross. Num- ber of Stalks.! Grain yield. Stover yield. Mois- ture in shelled grain when ears were weighed. Water-free basis. Row No. Ears. In- crease over better parent. Weight. In- crease over heavier stover- produo Ing parent. Ears. In- crease over better parent. 1 3 Selection 159 X Selection 119. Selection 119, 1909 363 361 358 359 363 356 367 363 357 357 365 365 362 363 359 361 364 359 358 361 365 372 364 359 351 368 359 355 360 359 360 359 357 360 350 361 357 352 355 361 350 365 345 358 359 348 359 359 359 361 360 Pounds. ITS 195 167 198 190 144 187 191 177 145 183 204 140 184 180 142 168 191 142 183 196 103 170 178 138 166 197 117 169 175 173 173 180 1G8 167 186 147 180 193 138 169 185 179 215 174 164 204 186 163 184 181 P.ct. - 9 ' 3" ■■_■-■■ -16'" - 7 ' - 4 - 9 - 5 - 9 - 3 ■■■26"' 13 " o.'s' Pounds. 194 197 200 211 193 220 247 192 190 178 215 192 104 137 183 132 178 198 126 180 199 112 162 195 141 167 214 112 157 203 217 231 212 195 197 223 145 184 214 198 208 203 198 234 209 265 267 215 171 201 214 r.ct. - 2 - i " 12 ' -27 - 7 - 9 -18 ■-is'" -25'"' 6 -ie"" 1 Mi'e'"' P.ct. 3L4 28.8 28.5 30.0 28.8 30.2 31.9 28.8 28.8 27.2 27.7 28.8 22.1 22.2 28.8 27.6 26.7 28.8 24.8 26.3 28.8 19.9 25.5 28.8 23.8 27.6 28.8 25.6 25.5 28.8 27.2 29.2 28.8 30.7 30.0 28.8 26.0 27.4 28.8 27.4 29.3 28.8 32.2 29.2 28.8 33.7 32.0 28.8 28.1 29.8 28.8 Pounds. 122.1 138.8 119.4 138.6 135. 3 100. 5 127.4 136.0 126.1 105.6 132.3 14.5. 3 109.1 143.1 128.2 102.8 123.1 1.36.0 106.7 134.8 139.6 82.5 126.7 126.8 105.2 120.2 140.3 87.0 125.9 124.6 125.9 122.4 128.2 116.4 116.9 132.5 108.8 130.7 137.4 100.2 119.5 131.7 121.4 152.2 123.9 108.7 138.7 132.5 117.2 129.3 128.9 P.ct. -12 4 Selection 137 5 7 Selection 137 X Selection 119. Selection 119, 1909 1 8 Selection 138 9 11 Selection 138 X Selection 119. Selection 119, 1909 - 6 12 14 Selection 119 X Selection 119. Whitecap, original -10 15 17 Whitecap X Selection 119.... Selection 119, 1909 - 6 18 19 Ohio Learning, original Ohio Learning X Selection 119 5 21 Selection 119, 1909 22 23 Illinois Learning, original Illinois Learning X Selection 119 _ 7 25 Selection 119, 1909 . 26 27 Reid Yellow Dent, original.. Reid Yellow Dent X Selec- tion 119 — 2 29 Selection 119, 1909 30 Sturges Hybrid Flint, origi- na 31 Sturges Hybrid Flint X Se- lection 119 — 5 32 Selection 119, 1909 33 Silvermine, original 34 35 Silvermine X Selection 119 . . Selection 119, 1909 -10 36 37 38 Golden Eagle, original Golden Eagle X Selection 119. Selection ll9, 1909 "J. "5 39 40 Fraley Yellow Dent, original. Fraley Yellow Dent X Selec- tion 119 — 3 41 Selection 119, 1909 42 Selection 77 43 44 45 46 47 48 Selection 77 X Selection 119.. Selection 119, 1909 Red Blaze, original Red Blaze X Selection 119.. . Selection 119, 1909 Cross 100 -10 ■■■"i;'3 49 50 Cross 100 X Selection 119 Selection 119, 1909 -11 51 Cross 120 52 53 Cross 120 X Selection 119 Selection 119, 1909 19 54 55 Hickory King, original Hickory King X Selection 119 8 56 Selection 119, 1909 57 Selection 78 58 59 Selection 78 X Selection 119.. Selection 119, 1909 - 1 12305°— Bul. 218—12- 1 Length of row 598 feet. -3 18 CROSSBREEDING CORN. Eleven of the fourteen crosses of distinct varieties produced less grain than the better yielding of the two parents. Wlien the pounds of ears harvested is reduced to a water-free basis, according to the percentage of water in the shelled grain at harvest time, the general results remain the same, namely, 11 comparisons in which the first- generation cross produced less and 3 in which it produced more than the better yielding of the two parents. In Table IV those crosses which produced better than either parent are classed as advantageous. The others are classed as disadvan- tageous. Table IV. — First-generation crosses of corn (male parent, Selection 119), showing pounds of grain produced {water-free basis) and classified as advantageous and disadvantageous. Yield. Female parent and classification. Of parent. Of cross. Increase over Female. Male. better parent. Disadvantageous — Crosses less productive than the better parent: Whitecap Pounds. 106 103 107 83 105 87 126 116 109 100 117 Pounds. 141 132 138 133 1.34 132 126 130 135 135 131 Pounds. 132 123 135 127 120 126 122 117 131 120 129 Per cent. - 6 Illinois Leamine. . - 7 Reid Yellow Dent - 2 Sturges Hybrid Flint - 5 Silvermine -10 Golden Eagle — 5 Fraley Yellow Dent - 3 Selection 77 -10 Red Blaze — 3 Cross 100 — 11 Selection 78. - 1 Average 105 133 126 - 6 Advantageous— Crosses more productive than the better parent : Ohio Leaming 109 121 109 137 128 128 143 152 139 5 Cross 120 19 Hickory Kine 8 Average 113 131 145 10 ADVANTAGEOUS CROSSES. Without consideration of water content the Oliio Leaming cross would be a disadvantageous cross, but the dryness of the ears, due doubtless in some degree to the earliness of the female parent, causes it to fall into the class of advantageous crosses with an increased yield of 5 per cent over Selection 119. A cross made in 1900 in which this strain of Leaming was used as male parent also produced dry and unusually solid ears. Cross 120 was originated in 1902 by planting occasional rows of Hickory King in a field of Selection 119. All Hickory King stalks were detasseled. Since 1902 Cross 120 and Selection 119 have been improved in yield and adapted to climatic and soil conditions near Washington, D. C, by yearly growing ear-to-row breeding plats and saving seed from the best stalks of the highest yielding rows. 218 TESTS IN MARYLAND. 19 It is of especial interest that these two unproved, acchmated, and related strains when crossed in 1909 should give a first-generation cross of much greater yielding power than either parent. This first-generation cross pro(hiced better than any of the other first- generation crosses and better than any of the other varieties tested. It is the only cross that produced far better than either parent in all four tests. By these tests the value of the seed of this particular first-generation cross for tlie conditions prevailing at these points in Maryland in 1910 has been demonstrated. These two strains are now being crossed extensively in producing seed for general planting. This cross-pollinated seed is designated " First-Generation Cross No. 182." The third and last advantageous cross of the 14 crosses, as classi- fied in Table TV, is the same cross that gave origin to Cross 120 which, after six years of selection and adaptation, produces some- what less than the first-generation cross of the same parents made in 1909, after each parent has undergone six years of selection and adaptation. This fact mdicates that it is more j^rofitable to acch- mate and improve the parents of an advantageous cross separately and cross them yearly to obtain seed than to cross them once and then rely upon the acclimatization and improvement of the cross. Furthermore, since Cross 120, after six years of improvement, when crossed with Selection 119 gives a first-generation cross of superior productiveness, it would seem that the recrossing of a cross some- times gives better seed than the crossing of the origmal pure-bred varieties. The advantage may be due to adaptation, as one of the original parents. Hickory King, has not been adapted to conditions near Washington, D. C. DISADVANTAGEOUS CROSSES. The Whitecap variety is adapted to conditions in Delaware, where it is quite extensively grown. It yields a very large ear, with a large cob, and yellow kernels with white caps. Neither in weight of ears as harvested nor on a water-free basis did the first generation cross of Whitecap and Selection 119 produce, as weU as the male parent. The Illinois Learning, though a pure selection from the Ohio Leaming, is now very unlike it in appearance. The Illiriois Leaming is of a rougher type, with broader kernels. According to pounds of ears at harvest the crosses of the two strains of Leaming with Selection 119 fell below the male parent in production. The Illmois Leaming cross did not produce as well as the Ohio Leaming cross, and the grain contained more water at harvest time. Making the comparison of yields on a water-free basis the Ohio Leaming cross is advantageous and the Illinois Leaming cross is disadvantageous. 218 20 CROSSBREEDING CORN. Sturges Hybrid Flint, tlie only flint variety used in these experi- ments, is a.v«large-eared yellow corn adapted to Connecticut condi- tions. It has stalks considerably shorter than those of the male parent and is 20 da^'s earlier. The cross was intermediate between the two parents in size and time of maturit}'. The first-generation cross produced much better than the female parent, but not quite as well as the male parent. Silvermine, a white dent, and Golden Eagle, a yellow dent, are the earliest varieties used in these experiments except Sturges Hybrid Flint. Their first-generation crosses with Selection 119 produced much better than the female parents, but not quite as well as the male parent. In comparison with the results from this same seed as tested in California (discussed later) it should be noted here that, wliile in ^Maryland Silvermine is but an average producer and Golden Eagle is second to the poorest of all the varieties, under California conditions both these varieties rank very high in production. Fraley Yellow Dent is the variety that for 15 years has been grown on the Derwood farm on which two of these four tests were made. It is a productive variety adapted to the conditions at Derwood and unrelated to Selection 119. Among the 14 fii'st- generation crosses tested this is the only instance m which both parents are more productive than the first-generation cross. The 1908 seed of the female parent produced slightly better than the cross. Except that Fraley Yellow Dent differs in color from the male parent and has not been improved by ear-to-row selection, the conditions of this disadvantageous cross are similar to those of the most advantageous cross of the series, both parents being well adapted to climatic and soil conditions and highly productive. Selection 77 resembles Cross 120 and like it has undergone man}'' years of selection. Cross 120 is adapted to Maryland conditions, and Selection 77 to Scioto River Valley conditions in Ohio. With Selection 119 as male parent Cross 120 makes a higldy advantageous cross and Selection 77 a disadvantageous cross. Cross 100 was made at the same time (1902) and in the same manner as Cross 120, Boone County White being the male parent m each case. Hickory King, a broad-kerneled small-cobbed corn, was female parent of Cross 120, and Dotson, a long-kerneled, small- eared, small-cobbed corn, was female parent of Cross 100. The two crosses have had similar ear-to-row selection smce 1902. Cross 100 has yearly been grown on poorer soil than has Cross 120. Although of such similar history and treatment, when these crosses are crossed with the related variety, Boone County White, one 218 TESTS IN MARYLAND. 21 makes a highly advantageous first-generation cross and the other a disadvantageous first-generation cross. Of all the varieties used as female parents, the most productive and the seven least productive formed disadvantageous first-genera- tion crosses with Selection 119. COMPARISON OP FIRST-GENERATION CROSSES WITH THE 1908 SEED OF BOTH PARENTS. Although placing the odds in favor of the crosses, a comparison is here made between the productiveness of first-generation crosses and that of the parents as grown from the original (1908) seed. There are 31 instances in which the first-generation cross occu- pied a row between rows of either parent in which the 2-year-old seed was planted. In these 31 comparisons the cross exceeds the better of the two parents in 14, equals it in 1, and produces less in 16. Of these 16 cases the male parent exceeds the cross in 15 and the female parent (the Fraley Yellow Dent variety) once. It should be noted here that if these Maryland tests had been restricted to the original seed of the parents, as has been done in a few reported tests of this nature, the first-generation crosses would have stood much higher in production in comparison with the parent varieties. RELATIVE GRAIN PRODUCTION OP PARENT VARIETIES AND FIRST-GENERATION CROSSES. Expressed in terms of bushels per acre, allowing 70 pounds of ears containing 15 per cent of moisture to the bushel, the parents and crosses rank as follows for the four tests combined: Male parent, 1909 seed 49 First-generation crosses, 1909 seed 47 Male parent, 1908 seed 45 Female parents, mostly 1908 seed 39 This relative production is shown in figure 1. As the yield for each field row shown in the diagram is the combined yield of a row from each of the four tests, the curves show the relative production of the different lots of seed with fluctuating variations and varia- tions due to soil conditions somewhat reduced. The four Maryland tests show the production of the crosses in general to be much above the average for the parents and somewhat below the male parent. Of the 14 crosses between distinct strains the cross of Cross 120 with Selection 119 is the only one that is remarkably superior to Selection 119 for the soil and climatic con- ditions under which the tests were conducted. The increased 218 22 CROSSBREEDING CORN. productiveness of this cross seems sufficient to warrant the crossing of these two strains in producing seed for general use in Maryland and Virginia, where conditions similar to those of the tests exist. As 1909 seed of the male parent occupied every third or fourth row in all four of the tests, a check or standard is afforded for com- paring the productiveness of all the varieties and crosses. In Table V the varieties and first-generation crosses are classified and arranged in separate columns in the order of their productiveness, the most productive being mentioned first and ranked as 1. In computing the comparative productiveness of the varieties and crosses for this table the yield of a variety is decreased or increased proportionately / S m /S 20 25 30 JS ^0 ^5 SO SS S9 S6 /SO i C Af^ - l^-'^^^r^ /\\w ^'l Si' iiU:''T/\l!f"'^J-' ^HmH /^>^ ti. ^^ r's -' \ " . t" T^ i/ y k i-.L. - . . - /2o\ It h /"' A 1 \ / > :\tXV4--X ^^i 1 "i 3" L_ 1 1.. I ez -^ Fig. 1.— Diagram showing the relative production of parent varieties of com and their first-generation crosses in Maryland, 1910: A, Male parent, variation of 1909 seed; B, male parent, mean of 1909 seed; C, mean of crosses; D, variation of crosses; E, male parent, variation of 1908 seed; F, male parent, mean of 1908 seed; G, variation of female parents; H, mean of female parents. as the average yield of the two nearest rows of Selection 119 exceeds or falls short of the general average of Selection 119 for all rows in all the tests. From the seven best female parents the crosses of six are found among the seven best crosses, Selection 77 being the only high- producing variety whose cross is a poor producer. ^Uong with this indication that the productiveness of the parents influences the productiveness of the cross there are sufficient exceptions to indi- cate that the productiveness of a first-generation cross is sometimes determined to a great degree by other factors. 218 TESTS IN MARYLAND. 23 Table V. — Parent varieties and crosses classified and ranked according to the computed production of ear corn {basis of 15 per cent moisture). Rank. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 First-generation cross (X Selection 119). Cross 120 Hickory King. Ohio Learning. Selection 78 Reid Yellow Dent Fraley Yellow Dent. . Red Blaze Sturges Hybrid Flint. Golden Eagle Whitecap Illinois Learning. Silvermine Selection 77 Cross 100. Parent variety. Selection 119 (average for 60 rows). Fraley Yellow Dent Cross 120. Selection 78. Selection 77. Hickory King Red Blaze Ohio Learning Silvermine Illinois Learning Reid Yellow Dent "Whitecap Cross 100 Golden Eagle Sturges Hybrid Flint. Yield per acre. Btisheh. 58 53 51 49 48 48 47 47 47 46 46 46 46 45 44 44 44 43 43 41 39 39 38 38 38 36 36 32 30 STOVER WEIGHTS OP PARENTS AND CROSSES COMPARED. As no determinations were made of the water content of the stover, a comparison of weights of stover at liarvest time does not repre- sent food value and is of httle importance except in indicating the earliness of maturity of the crosses and parent varieties. The stalks of the later maturing varieties contained considerable sap when weighed the latter part of October, while those of the earlier matur- ing varieties contained very little sap. In 4 cases out of the 14 the stover weight of the crosses is lighter than the average of the two parents. In 3 of these 4 cases the female parent matures fully 10 days earlier than Selection 119. In general, the crosses seemed intermediate between the parents regarding height and time of maturing. It seems that the earlier maturing parents transmitted to their crosses their early-maturing character in sufficient degree to cause the stover to weigh less than the average for the two parents. Sturges Hybrid, the only flint variety in the test, is an exception in this respect. In no instance was the stover weight of a cross as light as that of the lighter pro- ducing parent. The cross of Cross 120, which gave so remarkable an increase in grain production, also gave 14 per cent increased stover weight over 218 24 CROSSBEEEDING CORN. the heavier producmg parent and 16 per cent increase over the average of its two parents. The 'VMiitecap cross also gave 16 per cent increase over the average of its two parents and 12 per cent over the heavier producing parent, but in grain production it fell 6 per cent below the better of its two parents. Of the 14 first-generation crosses of distinct varieties 10 produced fewer pounds of stover than the heavier yielding of the two parents. CORN CROSSES AT CHICO, CAL., 1910. CONDITIONS OF THE TEST. The crosses made in 1909 in Marjdand were also growTi at Chico, Cal., in 1910, in comparison A\ith their parent varieties. The plant- ine:s were so arrano;ed that each row of the cross came between rows of its parent varieties. The soil upon which these plantings were made was medium loam which had gro\\^l alfalfa for four years previous to 1910. The land was broken to a depth of about 10 inches in December, 1909, with a second breaking in April, 1910, to a depth of 6 inches, and marked out in shallow furrows 3^ feet apart. Both plowings were made in lands running north and south and the corn rows were marked out east and west, so that no rows would fall on dead or back furrows. On April 14 three kernels were dropped by hand in each hill in the furrows and lightly covered with the foot. Hills were 3| feet apart in the row and 80 to each row. Four cultivations were given during the season. On account of the surface soil being somewhat dry at planting time and some seed being taken by gophers, an uneven stand resulted. The rainfall after planting amounted to less than one-half inch and no irrigation was given. Sufficient water was contained in the soil early in the season to give all varieties a good growth of stalk, the average height being about 8^ feet. This moisture supply was not great enough, however, to produce a good crop of ears. Many of the ears were small and about 25 per cent of the stalks were barren. The number of stalks per row, number of hills, average number of stalks per hill, pounds of ears per row, average number of pounds per stalk, percentage increase in yield per stalk of cross over the better parent, number of good and poor ears, and weight of stover are given in Table VI. 218 CORN CROSSES AT CIIICO, CAL., 1910. 25 The order of plantings is preserved in the table, but for greater ease in comparing the cross with its parent varieties each row of Selection 119 is given twice. The yield per stalk of the different varieties is represented graphi(;- ally in diagram 1. Diagram 1 —Variation in yield per stalk of crosses and parent varieties of com at Chico, Cal, 1910} Field row No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Variety and cross. Pound. 0.0 0.1 0.2 0.3 0.4 Selection 119 Illinois LeamingXll9 Illinois Learning Selection 78 Selection 78X119 Selection 119 Reid Yellow DentXll9 Raid Yellow Dent Fraley Yellow Dent Fraley Yellow Dent X 119- - - Selectionll9 SilvermineXll9 Silvermine Selection 137 Selection 137X119 Selection 119 Selection 138X119 Selection 138 Hickory King Hickory KingXll9 Selection 119 Golden EagleXll9 Golden Eagle Whitecap WhitecapXUg Selection 119 Cross 100X119 Cross 100 Selection 159 Selection 159X119 Selection 119 Ohio LeamingXll9 Ohio Learning Sturges Hybrid Flint Stiirges Hybrid FlintXll9 . Selection 119 Selection 77X119 Selection 77 Selection 119 (1908) Selection 119 (1908)X119.-.. Selection 119 Cross 120X119 Cross 120 Red Blaze Red BlazeXll9 Selection 119 1 The yield of first-generation crosses is indicated by the heavier lines. 12305°— Bul. 218—12 4 26 CROSSBREEDING CORN. Table VI —Tests of production of parent varieties and first-generation crosses of com at Chico, Cal., 1910. 1 Variety and cross. 1 55 2 "3 m Yield. AVeight of ears. Number of ears. Weight of stover. 6 1 2 a ■3 M t-i P.1 11 ■6 0 0 0 8 1 1 Splpfition 119 169 140 111 131 142 155 155 122 146 142 149 159 159 160 107 108 148 147 147 141 146 122 129 103 163 144 122 109 116 126 126 123 121 99 107 115 115 114 102 79 106 80 80 95 71 95 83 95 95 111 75 67 111 89 72 65 50 52 61 71 71 56 68 67 70 68 68 68 60 60 64 63 63 67 69 59 00 70 70 66 58 50 59 53 53 61 58 53 54 52 52 53 54 49 50 41 41 44 35 45 50 46 46 59 39 37 57 44 2.4 2.1 2.2 2.5 2.3 2.2 2.2 2.2 2.1 2.1 2.3 2.4 2.4 2.3 1.8 1.8 2.3 2.3 2.3 2.1 2.1 2.1 2.1 2.3 2.3 2.2 2.1 2.2 2.0 2.4 2.4 2.0 2.1 1.9 2.0 2.2 2.2 2.1 1.9 1.6 2.1 2.0 2.0 2.2 2.0 2.1 1.7 2.1 2.1 1.9 1.9 1.8 1.9 2.0 Lbs. 41 37 28 31 35 35 35 34 41 27 32 34 34 51 41 31 47 39 39 50 50 27 39 58 58 64 47 26 37 37 37 40 21 26 31 37J 37§ 37 39 19 35 29i 29i 30i 27 23* 31' 29i 29J 41 25 22 43J 22 Lbs. 0.242 .264 .254 .247 .248 .226 .226 .278 .281 .190 .215 .214 .214 .318 .383 .287 .331 .265 .265 .355 .342 .221 .303 .3.56 .3.56 .445 .385 .238 .319 .294 .294 .325 .173 .263 .290 .326 .326 .324 .382 .241 .330 .369 .369 .369 .380 .248 .373 .310 .310 .373 .334 .328 .395 .247 P.ct. ""0 "Hi" ""0 '-17' "is ""4 '-is' "ie" ""s ...... '-ii' '—is' '-ii' "6' "26' '"12 '"26 52 48 40 48 52 40 40 52 57 38 40 36 36 65 55 42 60 57 57 62 68 56 72 74 74 92 72 35 44 37 37 55 52 34 40 46 46 50 64 40 52 42 42 36 44 26 32 36 36 45 43 38 64 26 75 68 48 42 57 68 t 51 58 60 75 75 68 54 58 60 68 68 72 70 62 52 80 80 47 42 52 56 69 69 60 63 54 57 57 57 62 40 40 60 40 40 52 32 63 63 52 52 68 37 38 54 58 Lbs. 130 106 69 83 106 137 137 85 97 118 133 121 121 123 70 99 134 117 117 156 135 106 122 132 132 120 75 110 129 110 110 113 101 85 104 111 111 92 60 67 106 77 77 90 70 93 94 93 93 125 67 54 97 80 Lbs. 0.770 2 Tllinoi"? Tjeaminey 119 .757 3 Tllinois Leamiiitr- .622 4 Splpotlon 78 .633 5 Selection 78X119 .747 G Selection 119 .884 c Selection 119 .884 7 Reid Yellow DentXll9 .697 g Reid Yellow Dent .665 9 Fralev Yellow Dent .832 10 11 Fraley Yellow DentXll9 Selection 119 .894 .761 11 Selection 119 .761 1? SilvennineXll9 .769 n SUvennine .654 14 Selection 137 .916 15 Selection 137X119 .906 16 Selection 119 .796 16 Selection 119 .796 17 Selection 138X119 1.105 18 Selection 138 .925 19 Hickorv Kine .870 90 Hickory KingXll9 .946 ?1 Selection 119 .810 91 Selection 119 .810 20 Golden Eaglexll9 .834 93 Golden Eagle .615 ''•1 Whitecap 1.010 95 WhitecapX119 1.113 96 Selection 119 .872 96 Selection 119 .872 27 Cross 100X119 .918 ?8 Cross 100 .834 •X) Selection 159 .859 30 Selection 159X119 .972 31 Selection 119 .965 31 Selection 119 .965 32 Ohio LeamingX 119 .806 33 Ohio Leamine .587 34 35 36 Sturges Hybrid Flint Sturges Hybrid Flint X 119 Selection 119 .849 1.000 .961 36 Selection 119 .961 37 Selection 77X119 .946 38 Selection 77 .986 39 Selection 119 (1908) .930 40 Selection 119X119 1.130 41 Selection 119 .930 41 Selection 119 .930 4? Cross 120X 119 1.125 43 Cross 120 .893 44 Red Blaze .806 45 Red BIazeXU9 .875 46 Selection 119 .900 218 CORN CROSSES AT CHICO, CAL., 1910. 27 COMPARISON OF CROSSES WITH PARENT VARIETIES. It has been claimed, though not universally accepted, that first- generation corn crosses are superior in pro(hicing power to the varieties crossed. The (hita herein submitted seem to bear out such a conclusion when the majority of cases and the average of all are considered. Of the 18 crosses included in this test, only 2 do not exceed in yield the average of the two varieties crossed. The average yield per stalk of the 10 plantings of Selection 119 is 0.280 pound; for the 18 varieties used as female parents, 0.284 pound; and for the crosses, 0.320 pound; an increase of 0.038 pound per stalk in favor of the average of the crosses. There is no special advantage in growing first-generation crosses unless such crosses can be depended upon to yield consistently and constantly more than either of the varieties used in making the cross. This gain must be sufficiently large to insure compensation for the rather careful work necessary in making the cross and in keeping pure two varieties of corn for tliis purpose. Of the 18 crosses in this test, 9 exceed either parent in the yield per stalk, and 9 are e([ualed or exceeded by one or the other of the parents. The difference in the yields of the better parent and of the cross ranges in amount from 4 to 20 per cent in the 9 comparisons in which the crosses exceed, and from zero to 17 per cent in the 9 in which the better parent exceeds the cross. Not only are there the same number of comparisons in which the cross exceeds and fails to exceed the better parent, but the average yield per stalk of the crosses and that of the better parents is the same, being 0.320 pound in each case. These data do not show that first-generation crosses can, in the greater number of cases, be depended upon to produce more than the better of the two varieties crossed. Two additional crosses were grown in the test at Chico. The male parent used was Selection 160, a large yellow flint. This corn has been grown in California for 12 years or more and at Chico for 5 years. It seems to be well acclimated and has proved to be the best yielder of a number of varieties grown at Chico in the last 3 years. The two varieties used as female parents were Ohio Leaming and Silvermine. Next to Selection 160 these have been the liighest yielding of the varieties tested at Chico. The crosses were made by hand-pollinating ears of these two varieties with pollen from Selection 160 in the varietal test rows at Chico in 1909. Several ears in each variety were also poUinated with pollen from different stalks of the same variety. In this way seed of the cross and that of the female parent used in the experiment 218 28 CKOSSBREEDING CORN, in 1910 was grown under identical conditions in 1909. Tlic Selection 160 seed was also taken from the 1909 crop and from detasseled stalks in a near-by, though sutliciently isolated, field. These two crosses are compared with their parent varieties in Table YII. Table VII. — Relative productiveness of first-generation crosses and parent varieties of corn crosses viade and tested at Chico, Cal. Variety and cross. Stalks. Hills. Stalks per hill. Yield. Weight of ears. Number of ears. Row No. In row. Per stalk. De- crease per stalk under better parent. Good. Poor. 47 Silvern! ine 149 139 140 140 152 144 65 61 64 64 63 67 2.3 2.1 2.2 2.2 2.4 2.1 Pounds. 54 53 59.5 59.5 60.5 42 Pounds. 0.362 .382 .425 .425 .398 .282 P.ct. io' 9' 72 88 112 112 HI 58 52 48 49 SilvennineXSelection 160 Selection 160 46 44 49 Selection 160 44 .50 51 Ohio LeamingX Selection 160. Ohio Learning 61 50 RELATION OF ADAPTATION AND YIELD OF PARENT VARIETIES TO THE BEHAVIOR OF THE CROSSES. Since there is a wide range of variability in the behavior of crosses between different varieties, it is of importance to discover, if possible, whether these differences have an}^ relation to the yielding power of the parent varieties. In this test, as is usual in a series of varieties collected from differ- ent localities and subjected to adveree conditions, a wide chfference exists in the response of the different varieties to these conditions. Since all of the varieties are well selected and improved for the locali- ties from which they came, the yield of each may be taken as an indication of its adaptation to the con(Htions of the test. The highest yielcUng crosses (x Selection 119), arranged accorchng to productiveness, are: Golden Eagle, Red Blaze, Cross 120, Selec- ti(m 77, and Selection 138. A comparison of the yields of the original varieties shows that tlie female parents of these crosses rank in pro- ductiveness as follows: Golden Eagle, lirst; Red Blaze, seventh; Cross 120, sixth; Selection 77, fourth; Selection 138, fifth. The fact that the female parents of these high-yielding crosses rank high in yield among the original varieties is an indication that the adaptiv- tion and i)i()(ki(tivity of the parent variety determine the adaptation and productivity of tlie cross to some extent; or, in general, the highest yielding crosses may be expected to result from crossing the 218 CORN CROSSES AT CHICO, CAL., 1010. 29 highest yiekhng varieties. This view is supported by the results of a test of the same varieties and crosses in ISIarylanrl and also by the results obtained from the two crosses with Selection 160. While this influence apparently exists, it is not sufficiently constant to be relied upon, as is shown by comparing the crosses Silvermine X Selection 119 and Ohio Learning X Selection 119. The female parents of these crosses rank second and third in yield among the original varieties; the crosses are surpassed in productiveness by the crosses Sturges Hybrid Flint X Selection 119 and Cross 100 X Selection 119, the female parents of which rank low in yield. The four best producers of the original varieties are Golden Eagle, Silvermine, Ohio Leaming, and Selection 77. The crosses of these four varieties with Selection 119 are distributed in the following manner as regards the degree of benefit from crossing: One case in which the cross shows a decided increase over the better parent, one in which the cross is intermediate between the two parents, and two in which the cross about equals the poorer parent. The five poorest producing varieties are Cross 100, Fraley Yellow Dent, Hickoiy King, Whitecap, and Sturges Hybrid Flint. The crosses of these five varieties with Selection 119 are distributed as follows as regards benefit from crossing : Three better than the better parent, and two intermediate between the two parents. The crosses with Selection 119 that show the greatest gain in yield over the better of their two parents are those of Red Blaze, Golden Eagle, Selection 137, and Cross 120. If yields of the original varieties and of the crosses are both considered, the female parents of these high-yielding crosses may be classed as one good and three interme- diate in respect to yield. From the examples set forth in the preceding paragraphs it would seem that no constant relation exists between the productivity of varieties and the increase or decrease in yield of their crosses as compared with the parent varieties. The lack of constancy in this relation may be seen in the following crosses: Ohio Leaming X Selection 119 produces less than either parent, although both are high-yielding varieties that have been pure bred for many years; the cross of Red Blaze (a high-yielding and well-selected variety) X Selection 119 gives an increase in yield of 20 per cent over the better parent; the cross of Cross 100, the lowest yielding variety in the test, vnth Selection 119 gives an increase in jaeld of 11 per cent over the better parent and practically equals in yield that of Ohio Leaming X Selection 119 (ranking eighth in yield among the crosses); while Fraley Yellow Dent, the next lowest yielding variety, crossed with Selection 119 is the lowest yielding cross in the test and is exceeded by all the varieties except Cross 100 and Fraley Yellow Dent. 218 80 CROSSBREEDING CORN. These results show that some varieties combine or "nick" well' when crossed, forming crosses that arc superior in yielding power to either parent, while other varieties do not combine well and the crosses are either less productive than the better parent or inferior to both parents. The factors that determine what the productive- ness of the cross will be are not known, and apparently no external characters are discernible by which we can judge of their presence or absence. It is important, therefore, that crosses of varieties should be tried experimentally to ascertain their productiveness before growing them commercially or before making a general agricultural application of tliis method of corn breeding. It is worthy of note that the crosses which produced best under the somewhat adveree conditions at Chico are not from the same combi- nations as those which produced best under conditions of normal rainfall in Marvland. Table VII shows a comparison between an acchmated, well-adapted variety, the crosses of this with two varieties of later introduction, and these two varieties themselves. In each of tliese comparisons the cross is intermediate in yield per stalk between the two varieties crossed. In other words, nothing was gained in yield by crossing an adapted, well-acclimated variety with a variety of later introduction, even though this variety is also a good yielder. TESTS IN TEXAS. WORK OF 1909. Seed of a number of pure-bred varieties of corn was obtained early in 1909 for use in crossbreeding experiments in Texas A list of these varieties and a brief description is given in Table VIII. The varieties were planted at Waco, Tex., early in March, 1909, one row of each of the other varieties alternating with two rows of Chisholm (the variety chosen to be the male parent). Tassels were removed from the stalks of all varieties except the Chisholm before any pollen had been shed. The crosses made in this manner, each lmA"ing the same male parent but a different female parent, were planted in 1910 at Sherman, at Waco, and at Corsicana. 218 TESTS IN TEXAS. ai "a n gg . CO C3 b4 fr- u o V « 3.S HI c3 I I I ^ '7 CO CO CO CO CO xoocooor~cD CO CO t^ CO l^ t^ 1^ I- r^ i^ II I I a C3 p CD » d a 5^ a X) o o o o o ^ « o 13 O 13 00 P o B s 1 00 I s 8 tS PQ ■< M 3 OB 51 u^i I o Id o « bX) a o CO CO o:j w O t, O CO ra CO l_i *^ r^ ^ ^ ni «0 c3 03 "^e 03 . CU <3^ o H qi t t^lO ^>o to O O w w O O CA CO k^ K<< O) a 03 C3 S £ C3 Q> © o ^^ '^ a> ia d c fc fc a 52 S ■* Sim ^ X <1^ Qi> c b "-• r oi o ■^^ +J +J CO fc-< f-1 03 O 5 tic a _o ^ o "e S? * >>(*> too coco X 3 o o H^ Ss ■^ !;1 -^ 'I' ,J o ^§SE -M -fc^ -*-^ -M e 3 b 3 Q> Ok2 o CO tH 03 CO 03 X > "rt ■^ (Tl a !-l VH ^ fl o 0) m o CO S o 03 CO 03 y, HI a o be 03 4J a £ 03 Ph I o o • CO O Qi P-g§ ■r '^ d te 03." ^ >.£P h >- " B >> 03 O u> Ph CO 03 X Eh « X5 "" o ° S> C3-? S'-B t>>03 : * o ° e5 CO > d d — 03 ■3 K — O d ■g >H 3 d — 3c3O'"^^>031> ^jK o._ « P, ^ ft O CO = i d ' 1^ w 03 : P< CO 03 ,dx: s ■ " ris; -t^ Jh ^ t- -t- ; C3 03 O g O 03 eH;z;^M 12; •c > 03 o «C 3 00 • ,d ® d a 2^ gbfO-g wtaSo 03 PL, d 03 V 1-3 S3m pit Ph o 3 CO o A o 218 32 CKOSSBEEEDING COEN. WORK OF 1910. TEST AT SHERMAN, TEX. The test at Sherman was located upon fertile black upland of uniform appearance. All the land used had been cropped the same the previous year, had been broken deep, and was in good condition when the corn was planted. The planting was made in hills 3^ feet apart each way; the crop was cultivated frequently, and the ground kept free of grass and weeds. The season at Sherman was extremely dry and the yields were very light. The order in which the varieties and crosses were planted and their field-row numbers are shown in Table IX. Because of lack of uni- formity in number of stalks per row of the different varieties, the comparisons have been made on the basis of production per stalk rather than on row yields. This method is followed in all cases. The comparison is made between the yield of the cross and the higher yielding of the two parents. For practical purposes the cross can not be regarded as an improvement upon existing conditions or as worthy of propagation unless it is superior to the better parent. Where the comparison is between the cross and male parent the average of the two rows of the male parent nearest the cross has been used. This was also done in the test at Waco and Corsicana. The seed of the female parents used in the experiment is in every case taken from the 1908 crop, that is, from the same lot of seed that was used for the beginning of the experiment in 1909. The seed of the crosses is from the 1909 crop. The seed of Chisholm (the male parent) is in part from the 1908 crop, but mostly from the 1909 crop, entirely so at Sherman and Corsicana, and also in the greater part of the Waco test. When the crop was harvested, determinations showed the per- centage of moisture to be approximately the same for the different varieties. Taking into consideration the unavoidable percentage of error, it was believed that notliing would be gained by calculating the yields to a water-free basis. In computing the production per stalk only the main stalks were considered, as the suckers were not productive at any of the three places. 218 TESTS IN TEXAS. 33 Table IX. — Comparative productiveness of parent varieties of corn and first-generation crosses at Sherman, Tex., in 1910. [Area of each row one-seventieth of an acre.] Row No. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Variety and cross. Chisholm Uuffinan X Chisholm Huffman Chisholm Schiebcrle X Chisholm Schieberlc Chisholm Munson X Chisholm Munson Chisholm Gourd Seed X Chisholm Gourd Seed Chisholm Lily of the Valley X Chisholm. Lily of the Valley Chisholm Blow X Chisholm Blow Chisholm Selection 130 X Chisholm Selection 136 Chisholm Surcropper X Chisholm Surcropper Chisholm Dan Patch X Chisholm Dan Patch Chisholm Selection 137 X Chisholm Selection 137 Chisholm Mosby Prolific X Chisholm Mosby Prolific Chisholm Gorham Yellow X Chisholm . . Gorham Yellow Chisholm Ferguson Yellow X Chisholm . Ferguson Yellow Chisholm McCullouph X Chisholm McCuUough Chisholm Singleton X Chisholm Singleton Main stalks per row. 76 101 106 81 107 101 84 100 97 79 96 98 89 100 95 78 101 101 84 100 101 81 106 100 94 93 94 89 102 92 81 103 92 101 103 96 101 101 98 95 98 100 100 96 98 Suck- ers per row. 3 17 39 4 7 5 6 19 21 1 13 4 0 7 6 2 27 11 3 9 13 8 3 6 8 8 5 7 22 6 8 15 35 10 17 13 14 10 13 6 3 10 10 12 0 Yield of ears (husked). Per row. Pounds. 9i 9 3 10 91 Hi 111 12 9 13 17 14 12^ 18i 16i 12§ 141 9 154 19i 16 lOi 23i 231 12 23 20i 12 17i 1G| 14 12 8 18 Hi Hi 13 12i 13i 15i 15' 13 15 111 11 Per stalk. Poundn. 0.125 .089 .029 .123 .089 .114 .140 .120 .093 .105 .177 .143 .140 .182 .174 .160 .144 .089 .184 .195 .158 .130 .219 .238 .128 .247 .218 .135 .172 .182 .173 .117 .087 .178 .141 .120 .129 .124 .138 .103 .153 .130 .150 .122 .112 In- crease over better .parent. Per ct. -28 -32 -21 16 -17 23 Number of ears. Good. 13 - 6 -33 -15 -22 Poor. 37 40 16 39 41 49 44 49 43 45 68 57 39 57 56 43 61 49 57 66 72 48 79 80 47 83 74 45 71 62 51 58 61 62 53 56 53 69 65 68 56 63 70 59 52 In 11 out of 15 comparisons the cross ranges from 2 to 33 per cent lower in yield than the better parent; in the remaining four com- parisons the cross oiityields the better parent by 5 to 23 per cent. TEST AT WACO, TEX. At Waco the test was located on deep Brazos Valley sand and the corn was drilled in rows 3 J feet apart. A late frost Idlled some of the plants and so interfered to some extent with the uniformity of the stand. For this reason the comparisons of yields, as in the test at Sherman, have been made on the basis of i)roduction per stalk. The stands of three of the crosses were so uneven and irregular 12305°— Bui. 218—12 5 34 CROSSBREEDING CORN, that the comparisons could not be regarded as of value, and accord- ingly have not been considered in the results. The order of planting the varieties and crosses and their field-row numbers are shown in Table X. Table X. — Comparative productiveness of parent varieties of corn and first-generation crosses at Waco, Tex., in 1910. [Area of each row one-seventieth of an acre.] Row No. Variety and cross. Main Suck- stalks ers per per row. row. 46 0 54 0 38 0 37 0 53 0 37 0 53 0 49 0 48 0 54 0 60 0 50 0 65 0 51 0 34 0 40 0 55 0 55 0 65 0 75 0 38 0 51 0 46 0 35 0 51 0 63 0 48 0 66 2 68 0 35 0 45 0 52 0 49 0 44 3 53 5 41 0 Yield of ears (husked). Per row. Per stalk. In- crease over better parent. Number of ears. Good. I Poor. 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 26 27 28 29 30 31 32 33 34 38 39 40 41 42 43 44 45 46 47 48 49 Chisholm SchieberieXChisholm Sehieberle Chisholm Singleton X Chisholm Singleton Chisholm McCuUoughX Chisholm McCullough Chisholm Ferguson YellowxChisholm Ferguson Yellow Chisholm Gorham YellowxChisholm. Gorham Yellow Selection 137 Selection 137XChisholm Chisholm Selection 136 Selection 136XChisholm Chisholm Surcropper Surcropperx Chisholm Chisholm Blow BlowxChisholm Chisholm Gourd Seed Gourd Seed X Chisholm Chisholm Munson Munson XChisholm Chisholm Mosby Prolific Mosby ProliflcXChisholm... Chisholm Pounds. 19 30^ 20 14 26i 18 20 24 15 20i 32 22 29 26 12 12 20 24 34 43 17 21 20 14 19 28J 22 m 42J 14 25 30 23 16 23 20 Pounds. 0.413 .565 .526 .378 .500 .486 .377 .490 .312 .380 .533 .440 .446 .510 .353 .300 .364 .430 .523 .573 .447 .412 .435 .400 .373 .452 .458 .583 .625 .400 .556 .577 .469 .364 .434 .488 Per ct. \ 29 21 23 -18 10 - 9 19 31 20 11 34 14 20 30 13 19 38 15 23 21 10 4 21 30 38 45 12 20 23 14 15 25 22 40 56 10 26 30 22 24 42 16 21 24 14 26 16 22 27 20 30 30 23 34 38 32 19 30 32 20 30 30 27 33 23 18 34 41 26 25 15 23 21 25 24 24 13 32 In 10 of the 12 comparisons the cross out34elds the better parent, the increase ranging from 3 to 20 per cent; in the remaining 2 com- parisons the cross yields 1 8 and 9 per cent less than the better parent. TEST AT CORSICANA, TEX. At Corsicana tlie test was located on sandv loam of medium fer- tility. The corn was planted in hills 3^ feet apart each way, culti- vated well, and kept free of grass and weeds. The planting was made in a difTerent manner from that at Sherman and at Waco, a smaller number of rows of Chisholm were planted and these were 218 TESTS IN TEXAS. 35 arranged so that two of the crosses were planted adjacent to tlie same row of Chishohn. One of the crosses (SchieberleXChishoJm) was cut by mistake when green and fed to stock. Tlie order of phmting the varieties and crosses, and tlieir fiehl-row numbers, together with the results of the test, are shown in Table XI. Table XI. — Comparative productiveness of parent varieties of corn and first-generation crosses at Corsicana, Tex., in 1910. [Area of each row one eighty-sixth of an acre.] Row No. 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 46 47 48 Variety and cross. Singleton Singleton X Chisholm Chisholm McCulloughX Chisholm McCullough Ferguson Yellow Ferguson Yellow X Chisholm. Chisholm Gorham Yellow X Chisholm. . Gorham Yellow Selection 136 Selection 136 X Chisholm Chisholm SurcropperXChisholm Surcropper Dan Patch Dan Patchx Chisholm Chisholm BlowXChisholm Blow Lily of the Valley Lily of the Valley X Chisholm Chisholm Gourd Seed X Chisholm Gourd Seed Munson MunsonX Chisholm Chisholm Mosby Prolific X Chisholm Mosby Prolific Selection 137 Selection 137XChisholm Chisholm Chisholm Huffman X Chisholm Huffman Main stalks per row. 74 76 70 78 75 83 83 84 77 69 83 80 65 87 79 78 84 85 95 77 75 74 67 78 76 77 84 76 85 81 68 77 75 77 79 77 Suck- ers per row. 6 2 4 0 2 0 0 4 0 0 0 5 0 3 0 2 12 3 5 3 2 0 5 7 0 3 4 0 8 11 0 0 3 4 8 0 Yield of ears (husked). Per row. Pounds. 23^ 24J 20i 27' 23* 34| 32 26J 30J 22 35 35 22 35J 33 34 39 30 34J 25 30i m 26 34* 3l| 25J 30^ 27 34 27i 25 28i 30 23 21* 18' Per stalk. Pounds. 0.317 .322 .293 .346 .313 .416 .386 .315 .396 .319 . 422 !437 .338 .408 .418 .436 .464 .353 .303 ..325 .407 .534 .388 .442 .414 .331 .303 .355 .400 .340 .368 .370 .400 .299 .272 .234 In- crease over better parent. Number of ears. Per ct. 2 ii' - 7 '2i' Good. 31 - 2 -14 24 27 28 32 30 40 40 30 40 20 48 40 23 40 36 44 38 35 36 26 26 51 28 40 28 28 32 35 52 52 30 32 28 24 24 16 Poor. 32 37 28 30 33 35 30 33 31 40 28 36 30 40 43 28 47 38 48 40 34 26 30 36 41 40 43 30 27 30 28 36 34 44 44 36 The cross outyields the better parent in 8 comparisons out of the 14, the increase ranging from 2 to 31 per cent; in the remaining 6 com- parisons the better parent outyields the cross by 1 to 9 per cent. THE THREE TEXAS TESTS CONSIDERED COLLECTIVELY. In considermg the three tests collectively the relatively higher production of the Chisholm variety (male parent) at Shei-man than at Waco and Corsicana is apparent. At Sherman it outyitdds the cross in 9 and the female parent in 10 out of 15 comparisons. At Waco it 218 36 CROSSBREEDING CORN. outyields the cross in but 2 and the female in 5 out of 12 comparisons. At Corsicana it outyields the cross m 4 and the female parent in 5 out of 14 comparisons. The results at Waco and Corsicana are prac- tically a reversal of the results with Chisholm at Sherman. The 5 varieties that outyield Chisholm at Sherman are Surcropper, Dan Patch, Selection 137, Lily of the Valley, and Ferguson Yellow Dent. The first three varieties are earlier maturing than Chishohii; their increase in yield over Chisholm is considerably greater than the increase of Lily of the Valley and Ferguson Yellow Dent over Chis- hohn. Tliis would indicate that the superiority of the first three varieties has been due cliiefly to their earliness, wliich made them particularly suited to the drought conditions that prevailed at Sherman in 1910. From previous experience there is reason to believe that durmg a normal season Chisholm would be considerably more productive than an}^ of these three varieties. The fourth variety (Lily of the Valley) is another strain of the same variety as Chisholm, its increase over Cliisholm is not especially significant, although perhaps indicating a slight superiority, as Lily of the Valley outyielded Chisholm also at Corsicana. The increase of Ferguson Yellow over Chisholm is slight, and can not be regarded as indicating very much, if any, superiority. Taking into consideration the aver- age behavior of Chisholm in all the rows m which it was planted, it perhaps should be considered as superior to any of the varieties for practical growing at Sherman. The relativel}^ greater productiveness of Chisholm in the Sherman test than at Waco and at Corsicana is due probably to the fact that Chisholm is a northern Texas variety, and the particular strain used in these experunents has been grown for many years on fertile black lands near Sherman. This doubtless has caused the variety to be better adapted to its en\aronment at Sherman than it was at Waco or at Corsicana. Its yields also indicate that it was better adapted to the Sherman environment than were the other varieties in the test. The higher yields of the three early maturing varieties does not seem to have been due to better adaptation, but rather that the abnormal conditions of the season were less disastrous to them than to the later maturing varieties. The increase of Ferguson Yellow Dent, itself a northern Texas variety, is so slight that no generalization is warranted that it is better adapted to the Sherman environment than is Chisholm. Of the varieties used as female parents none has been bred for any length of time for the conditions encountered at any of the three places. At Sherman the conditions were very adverse and the yields very poor. At Waco, in the Brazos Valley, conditions were more favorable. The soil retained the moisture better than the soil at 218 TESTS IN TEXAS. 37 Sherman and more moisture was available for the growing crop; higher yields were made, but Chisholm seems to be less suited to the conditions than most of the other varieties. The female parents made an increase of 223 per cent in average production per stalk over their average production per stalk at Sherman; the same increase for Chisholm is 186 per cent. The results at Corsicana were similar and as pronounced, although actual yields were lower than at Waco. As has been stated, Chisholm at Sherman, to which conditions it has been thoroughly adapted, outyielded the cross in 9 out of 15 comparisons. At Waco, planted in the deep, sandy soil of the Brazos Valley, conditions to which the variety is apparently not adapted, it is outyielded by the cross in 10 out of 12 comparisons. At Corsicana, under conditions to which it was apparently also not adapted, it is outyielded by the cross in 10 out of 14 comparisons. In the Waco and Corsicana tests the crosses in the majority of comparisons outyielded the parent varieties. None of the varieties used in the tests had been bred for any length of time for the environ- mental conditions encountered at either place. At Sherman the Chisholm variety, wdiich has been grown for many years in that locality, outyielded the crosses in most of the comparisons. This would indicate that in general a variety well adapted to its environ- ment is not improved nor its productiveness increased by crossing with other varieties possibly less adapted to the environment. Wliat results would be obtained by crossing varieties that have been bred in the same locality and under the same conditions for a long period will have to be determined by further experimental work. Although m this connection attention should be called to the fact that crosses with such varieties as McCullough, Ferguson Yellow, and Singleton (all established northern Texas varieties that have been bred under very smiilar conditions to Chisholm) are less productive than Chisholm. THE PRODUCTIVITY OF THE PARENT VARIETIES AND ITS INFLUENCE UPON THE PRODUCTIVITY OF THE CROSSES. In Table XII an attempt has been made to trace as far as the fifth or sixth rank in yield the factors showing to what extent the highest yielding crosses are progeny of the highest yielding varieties ; also to what extent the highest yieldmg crosses may be identical with the crosses showing highest percentage of gain over better parent. Table XIII is a similar enumeration of the poorest yielding varie- ties, poorest yielding crosses, and crosses showmg the greatest per- centage of decrease as compared with the better parent. In the Sherman test the six highest yieldmg crosses are identical with the crosses of the six highest yielding female parents, but they 218 38 CROSSBREEDING CORN. do not rank in exactly the same order as the parent varieties. The crosses shoAnng the greatest percentage of increase over the better parent are identical with four of the highest yielding crosses. In the list of poorest yielding crosses four are identical with four of the crosses of the poorest jaelding female parents with Chisholm. The crosses showing the greatest percentage of decrease as compared with the better parent are the same as the poorest yielding crosses and, with one exception, are progeny of the poorest yielding female parents. In the Waco test four of the highest jdelding crosses are identical with four of the crosses of the highest yielding female parents. Of the crosses listed as showing the greatest percentage of increase over the better parent four are identical with four of the highest yielding crosses, three are progeny of three of the highest yielding female parents, and two are progeny of two of the poorest yielding female parents. Four of the poorest 3delding crosses are progeny of four of the poorest yielding female parents. The two crosses that are less productive than the better parent are both progeny of low-yielding female parents. 218 TESTS IN TEXAS. 39 .c JtOCO 0 0 i CO*-H o^-t^ - 1*— 1 t^cOCD 1 ■w;C> 0 s 6^ 0 : :S& X a J ■3 > : :S5 : :-i Moi 0-=: 3UU 1 35^51^ lo«3 ^8&li :dd ■ * • • a. lO t^co»o cc ; -^ Tt*c^ t^oo 1 2^^ c^» ^-^ CD cc ■ CO!© -^ coo 0 »0 0 lO 1-" • ic '^ " CO ^ CO cd" ; c *"2 CO 0--' E X 13 :c^ „>- 5 .2 > c3 p. o r^ "-* o ^c^lf : !^-ga : 2Qo^,g 4^ ai r- IN iM lo b- ,2 ^ Tf- t~ QC 01 t^ g IM cc '^ -rco" i ^ico--!"- t. -"" ""O •a _cot^ - 4^ s^'S X S f3 -^ 2 -H u CU(M Qi '^ D.03 o^! 0^ "■^ K q; 0 S g§2^g : 03 0 ftow 0 3h ■;: 0 S T3 : c^sog-s .2 o3 >■ : 5 ffi s >^ ■S'-3 s§ : O-a 1^2 >. ^ ^ ^ 0 2- 2 a 5 o 'C -.' l^> ;c • c CCS ■ 3 03 ij _, CO' co-a ■a 0) »• CO i -gSfe^-g P< o3 0 ^ 0 -^ nil • C3 0 P.O°2 ^ « d ffl 0 >> 03 a 3 Ci .0 bl £ ! ^ 0 0 1 03 d 03 u O ID o 218 40 CROSSBREEDING CORN, Ol «M >>( sc" r3 C e cS H Sii 0 " _i 5.S .2 0 w tl^ 5; ■«6 MO ^ C *-■ e p. li o-o Ss V s g ^ "« i •to e OD OD 09 o •a ft; o be o o .a 0 O Vi o X .2 'u > 0 2 0 P* u ' — ' 0 c I-) a 0 © wj m QJ E a c C3 O Si X" .2 > ■Bum 03 O X" go . • . C/5 '^ •*-" 'd- "^ a a>i^ f>» c^ '^^ o c e 03 o o c (^ ^ C31C1 t^ O CN SO o M -^ TT -^ -^ C^ CO CC CC 00 ■ o •-Ttg N - . ■^ 2o loo C9 Q) •-. PASS'S wS^mS f-H '"' -*— CZ) §|o2c E^'3 tr° sa MO S 1=! n* o o ■^ c^ o o 1-" M o oS '^ o -^ "^ C^ CO C<) CD CO t^ 'q^ C^ C5CO CN CC CC CC CC E '? ^- g ® — m;h g 9 — E ^o> o ■So .M -^ |||e2 3 o fl o — KSSocQ o 'A 2 &■? SO 05 t* Ci CC c^ C^ 00 OC' ^ ^^ O O OOt-H O • £ "o E>> 3 o d CO ? C M ° 3 C .ill cox! crr -^^>Hg . p :-c ; M .. C 3 C3' 3 = o G E 3 o g t, 3 CJ c O^ ■J n Eh 218 1^ g I o O TESTS IN TEXAS. 41 In the Corsicana test four of the hi 4 9 1 0 9 10 0 5 5 5 4 6 3 8 2 7 3 10 0 8 1 8 1 10 0 5 5 5 2 0 9 8 2 7 3 8 1 10 0 10 0 9 1 7 3 10 0 3 6 10 0 8 2 5 4 I'l 3 8 0 10 0 10 0 3 4 10 0 9 1 7 3 5 5 5 3 9 1 10 0 7 2 5 5 9 1 5 5 8 2 10 0 0 7 6 3 1 S 2 10 0 8 2 7 3 10 0 0 10 10 0 8 0 3 4 9 0 0 2 10 0 10 0 10 0 7 3 10 0 2 7 6 3 8 2 3 7 4 6 7 3 5 5 8 2 5 5 8 2 8 2 4 5 4 5 10 0 0 10 9 0 4.2 Weak 4.0 Cocke Prolific: 7.9 Weak 1.9 Marlboro Prolific: 7.9 Weak 1.8 Mosby Prolific: Strong ..,...,...--.-...-.---.... 8.5 Weak 1.1 Native of Statesboro: 8.4 Weak 1.6 Rodgers White Dent: 9.5 Weak .5 Sanders Prolific: Strong .........---------- 5.3 Weak 3.6 7.0 Weak 2.7 Tindal: 9.2 Weak .6 2.3 Weak 6.3 Williamson: 7.8 Weak 1.6 An unusual quantity of this seed was planted in each hill and later thinned to the stand desired. When the com came up and started to grow, the vigor of the crossed and of the uncrossed plants was not noticeably different. The productiveness of the female parents in comparison with the first-generation crosses was tested at States- boro, and upon the same farm where the crosses were produced the previous year, but in a different field. The field had been brought into cultivation more recently than those used in 1909, and altliough not rich it was quite uniformly fertile. The seed was planted in hills, and two stalks were left to the hill. The stalks stood from 6 to 8 inches apart in the hill. The iirst mem- ber of each hill in a row was from the remnant seed, and the second member of the hill was progeny of the first, which had been cross- poUinated the previous year. PLAN OF TESTING PRODUCTIVENESS IN 1910. Diagram 2 shows the arrangement of this 1910 planting. The varieties were planted in alphabetical order, and their ears in numer- ical order. As shown in the plan, each hill, for example, of row 1 in section 1 contained two stalks; the first stalk was from original ear 1 of Aldrich Perfection, and the second stalk from an ear descending directly from ear 1 of Aldrich Perfection, and which was cross- pollinated in 1909 with pollen from Rodgers White Dent. 218 48 CROSSBREEDING CORN. ■a P. ^JS o i2 3'S"' 00 !-. B S O .2 o-^ Pp 03 ■■^tt: o S o a) C b § 2 tf b J3 ■13 -o oo 09 o b •Is s o CO !>. I S e S •§. o <2! 09 s -I O a, a 8 s x)2 q pTS.t; SS=«c Sale's OSS. -B P rS o 03 O " M < Q 5 0) j= o .1 ^^g£22^=5c H O GJ mow r* •*? -^ CO C O O O CO „ ; ■ - ;i2, t3T3 ?J2 §a CO §D:;2«i^-£^^ pI^.o; 03 2,°5o ® o -o S2Q"l5S - t-— i O fe O O* o ■« 2? 5! £i-0 SS mt~ Co O »< w— • O ^ o E^ J- 5 «-S-- c- ^ 2 w o e s '/I o Or-*-*.— -^CTJcS a, § O t£^r O u o O X ^3 S2 n -=ffi8' mqco s.inBuax West. coc^s-'rTj'ioiOcocot^cocoaiOiOO ^-c^icc^iCc^t^QCaso ^—c^cc-^iccoi^ocoso ^(NCO-^iO'COt^ryjCiO ^C^rC'^»C:Ol^00ClO .-HCM^O-^iOOt^GCOiO O" CO c o o OO wMCC-^iOCOt^GCClO -.^(NCO'^OOl--XC10 ^C^CC'^'-'T'-OI^OCOSO t^oociC ^c^wi'tcccr^cccio -co: ; cc r^ GC cs o — (N COTl> . OCCt^OlOl— — C^CC"^»OCOt^GCC10 1— lC^CC*«J'tOCOt^XOiO < M cc-* in CO a 03 a 03 a 3 o .a E co"^ic;ci^xc:c: ^CMro-^iOwi^occso -^c^ico-^icor-ccoiO "-"cscc-v fei o -J rj rt'T o --c i-x o>c — o) «•»"; cot- X cic — i (M cc -"r to co i^ oc ov o — M cq a 218 TESTS AT STATESBORQ, GA. 49 CONDITIONS FOR GROWTH. The land had been thoroughly plowed several weeks previous to planting. Just before planting, furrows were opened with a large shovel, which not only permitted planting below the level in moist earth, but also helped to throw to one side hidden obstructions that might interfere with a uniform thrust of the hand planters used. A marked wire was used to regulate both the spacing of the hills in the row and the spacing of the stalks in the liills. The writer and his assistant planted all of the seed. Each man carried seed for a certain member of the hill only, and together they planted each hill. On removing the planter from the ground the foot was placed upon the spot and the weight of the body was thrown upon it in stepping forward to the next hill. Care was taken to remove trash or any other obstruction that might interfere with proper planting. Nine square feet per plant were allowed, so that very little compe- tition for sunlight was possible among the plants. The rainfall was abundant except for a week or 10 days previous to tassehng. A liberal supply of commercial fertilizer was used. Abnormal growth (barrenness, smut, etc.) was very rare among the plants, but there were missing members of some hills and a few missing hills. However, in securing the data that follow, considera- tion was taken only of hills that grew under normal conditions and whose members seemed to have had equal opportunity and were normal. MANNER OF HARVESTING. The harvesting was done by four men. One carried a notebook and kept all of the records. Another carried a knife and selected and cut the liills of a row that were suitable. The other two men took the stalks as they were cut, one carrying the first member only and the other carrying the second member only. The fodder was- thus collected and carried to the end of the rows and there weighed, and the collective weights of the two members of each hill were recorded separately. The ears were then separated from the stover, and the weight of each together with the number of ears was recorded. MOISTURE IN GRAIN HARVESTED. Through the courtesy of the Office of Grain Standardization mois- ture determinations were obtained of grain shelled from many ears of each variety and each cross. The extreme variation among the varieties and crosses was less than 2 per cent of moisture. The shelled grain of Aldrich Perfection and Whelchel contained 16 per 218 50 CKOSSBREEDING CORN. cent of moisture, and the other varieties and crosses contained about 1 per cent less. The appearance of the large cobs of the Whelchel and Aldrich Perfection varieties and the rotting of the ears indicated that the entire ears of these varieties contained a greater excess of moisture than did the shelled grain. In these two cases a correction for moisture content would give a more valuable comparison, but since the moisture content of the entire ears was not determined the comparisons of productiveness are in all cases based on the weight of ears as harvested. PRESENTATION OF RESULTS IN GEORGIA. DATA COLLECTED AT HARVEST. Table XVI gives in detail the data collected at harvest time in 1910. Table X^'I. — Yield record of 11 varieties of corn and their crossed progeny tested at Statesboro, Ga. Aldrich Perfection ? X Marlboro Prolific (f.i Num- Seed ber ear of No. perfect hills. 1 14 2 8 3 12 4 19 5 12 6 14 7 13 8 8 9 16 10 16 Kind of product. Weight of product (pounds). Total. Origi- nal. Cross. Per stalk. Origi- nal. Cross. Differ- ence. Per cent of differ- ence. Number of ears produced. Origi- nal. Cross. /Ears . . \Stalks, /Ears.. \Stalks /Ears.. \S talks /Ears.. \Stalks /Ears.. \StaIks, /Ears.. \Stalks /Ears.. \Stalks (Ears.. IStaUcs /Ears.. \Stalks /Ears.. \Stalks 9.75 13.75 4.25 6.25 5.75 8.75 11.00 15.25 6.75 10.00 4.25 17.00 8.50 16.25 5.00 8.00 4.50 15.75 8.75 13.00 9.50 14.25 5.00 8.25 7.25 11.50 11.50 17. 25 7.75 11.50 8.50 12.75 6. 75 10.25 ■5.00 7.50 7.25 12. 25 8.00 11.25 0.70 .98 .53 .78 .48 .73 .58 .80 .56 .83 .30 1.21 .65 1.25 .63 1.00 .28 .98 .55 .81 0.68 1.02 .63 1.03 .60 .96 .61 .91 .65 .96 .61 .91 .52 .79 .63 .94 .45 .77 .50 .70 -0.02 .04 .10 .25 .12 .23 .03 .11 .09 .13 .31 - .30 - .13 - .46 .00 - .06 .17 - .M - .05 - .11 - 3 4 18 32 26 31 5 13 15 15 100 - 25 - 21 - 37 0 - 6 61 - 22 - 9 - 13 15 8 'i2' 20 is" 14 "is 8 ie 'ie 14 "7 'i2 ig 'i2 "i4 "i3 "h "ih "io 1 Favoring the cross: Ears, 6 out of 10; stalks, 5 out of 10. Average weight of ears per stalk produced by the female parent, 0.52 pound; by the cross. 0.58 pound. Average weight of stover per stalk produced by female parent, 0.94 pound; by tlio cross, 0.88 pound. Increased yield of cross over the female parent: Grain, 12 per cent; stover, —6 per cent. 218 TESTS AT STATESBORO, GA. 51 Table XVI. — Yield record of 11 varieties of corn and their crossed progeny tested at Statesboro, Ga. — Continued. Aldrich Perfection $ X Rodgers White Dent cT-' Num- ber of perfect hills. Kind of product. Weight of product (pounds). Per cent of differ- ence. Number of ears Seed ear No. Total. Per stalk. produced. Origi- nal. Cross. Origi- nal. Cross. Differ- ence. Origi- nal. Cross. 14 21 8 24 14 18 15 17 8 12 yEars 8.00 9.50 11.25 17.25 3.25 7.25 13.25 19.50 7.25 11.00 8.50 14.00 9.25 14.50 9.25 14.75 3.75 6.25 7.50 10.75 6.25 12.50 13.00 20.25 5.00 8.00 13.25 21.00 8.00 12.50 11.50 16.75 9.75 16.00 11.00 17.75 5.25 8.00 6.75 10.50 0.57 .68 .54 .82 .41 .91 .55 .81 .52 .79 .47 .78 .62 .97 .54 .87 .47 .78 .63 .90 0.45 .89 .62 .96 .63 1.00 .55 .88 .57 .89 .64 .93 .65 1.07 .65 1.04 .66 1.00 .56 .88 -0.12 .21 .08 .14 .22 .09 .00 .07 .05 .10 .17 .15 .03 .10 .11 .17 .19 .22 - .07 - .02 - 22 32 16 17 54 10 0 8 10 14 35 20 5 10 19 20 40 28 -10 - 2 14 14 1 1 Stalks /Ears 21 21 2 1 Stalks (Ears 8 9 3 1 Stalks /Ears 24 25 4 1 Stalks /Ears 14 15 5 istnlks /Ears 18 20 6 1 Stalks /Ears 15 19 i is talks /Ears 17 17 8 1 Stalks /Ears 8 10 9 1 Stalks /Ears 12 12 10 1 Stalks COCKJE PROLIFIC ? X MARLBORO PROLIFIC (} ? 1 22 2 18 3 21 4 20 5 18 6 23 7 24 8 19 9 21 10 18 /Ears... \S talks.. iEars... Stalks.. Ears... Stalks.. /Ears... \Stalks., /Ears... \Stalks., /Ears... \Stalks. /Ears.. \ Stalks. /Ears.. \Stalks. /Ears.. \Stalks. /Ears.. Istalks. 10.25 17.25 10.50 16.00 9.00 13.00 10.00 16.50 10.50 16.00 10.75 17.25 11.75 20.25 11.00 17.00 9.00 14.50 11.00 18.25 10.50 16.00 10.50 15.75 10.00 14.25 8.75 13.50 10.25 14.75 13.50 20.50 12.50 19. 25 12.00 17.25 12.50 19.75 11.75 17.50 0.47 .78 .58 .89 .43 .62 .50 .83 .58 .89 .47 .75 .49 .84 .58 .89 .43 .69 .61 1.01 0.48 .73 .58 .88 .48 .68 .44 .68 .57 .82 .59 .89 .52 .80 .63 .91 .60 .94 .65 .97 0.01 - .05 .00 - .01 .05 .06 - .06 - .15 - .01 - .07 .12 .14 .03 - .04 .05 .02 .17 .25 .04 - .04 2 - 7 0 - 2 11 10 -13 -18 - 2 - 8 26 19 6 - 5 9 1 39 36 7 - 4 26 20 "2\ 21 '25' 29 "27' 24 28 24 23 23 '26 '25 28 25 28 '30 23 1 Favoring the cross: Ears, 7 out of 10; stalks, 9 out of 10. Average weight of ears per stalk produced by the female parent, 0.54 pound; by the cross, 0.59 pound. Average weight of stover per stalk produced by female parent, 0.83 pound; by the cross, 0.95 pound. Increased yield of cross over the female parent: Grain, 10 per cent; stover, 15 per cent. 2 Favoring the cross: Ears, 7 out of 10; stalks, 4 out of 10. Average weight of ears per stalk produced by the female parent, 0.51 pound; bv the cross, 0.55 pound. Average weigTit of stover per stalk produced by female parent, 0.81 pound; by the cross, 0.83 pound. Increased yield of cross over the female parent: Grain, 8 per cent; stover, 2 per cent. 218 52 CROSSBREEDING CORN. Table XVI. — Yield record of H varieties of corn and their crossed progeny tested at Statesboro, Ga. — Continued. Cocke Prolific $ X Rodgers White Dent cf •' Num- ber of perfect hills. Kind of product. Weight of product (pounds). Per cent of difTer- ence. Number of ears Seed ear No Total. Per stalk. produced. Origi- nal. Cross. Origi- nal. Cross. Differ- ence. Origi- nal. Cross. 13 18 21 18 12 14 21 23 21 15 /Ears 6.75 12.00 9.25 14.00 9.00 12.75 8.25 14.25 5.75 8.75 6.25 9.75 10.25 16.25 11.75 17.00 9.00 14.50 6.50 9.25 5.75 9.25 10.00 14.50 10.00 15.25 7.00 10.00 4.25 6.25 6.75 9.25 10.50 15.25 13.75 19.50 9.50 16.00 7.25 10.50 0.52 .92 .51 .78 .43 .61 .46 .79 .48 .73 .45 .70 .49 .77 .51 .74 .43 .69 .43 .62 0.44 .71 .56 .81 .48 .73 .39 .56 .35 .52 .48 .66 ..50 .73 .60 .85 .45 .76 .48 .70 -0.08 - .21 .05 .03 .05 .12 - .07 - .23 - .13 - .21 .03 - .04 .01 - .04 .09 .11 .02 .07 .05 .08 -15 -23 8 4 11 20 -15 -30 -26 -29 8 - 5 2 - 6 17 15 6 10 12 14 13 13 1 \st.alir,s /Ears 18 20 2 tstalks /Ears 22 22 3 \Stalks /Ears 20 18 4 \Stalks /Ears 13 12 5 tStalis /Ears 16 14 0 tstalks /Ears 22 21 7 tstalks /Ears 28 31 8 tstalks: /Ears 25 22 9 tstalks /Ears 16 17 10 tstalks Marlboro Prolific $ X MiRLBORO Prolific c?' 21 18 21 20 15 19 22 25 23 23 /Ears.. . 10.75 19.00 9.25 14.50 11.00 18.50 10.75 16.25 7.75 13.25 9.00 13.50 9.75 15.25 11.50 19.50 12.25 19.00 10.00 16.00 11.00 17.25 11.50 18.75 12.00 21.25 8.00 1.3. 25 6.50 11.25 10.00 15. 25 12.25 19.25 14.25 21.75 10.75 17.00 9.25 13. 75- 0.51 .90 .51 .81 .52 .88 .54 .81 .52 .88 .47 .71 .44 .69 .46 .78 .53 .83 .43 .70 0.52 .82 .64 1.04 .57 1.01 .40 .66 .43 .75 .53 .80 .56 .88 .57 .87 .47 .74 .40 .60 0.01 - .08 .13 .23 .05 .13 - .14 - .15 - .09 - .13 .06 .09 .12 .19 .11 .09 - .06 - .09 - .03 - .10 2 - 9 24 29 9 15 -26 -18 -16 -15 11 13 26 26 24 12 -12 -11 - 8 -14 27 27 1 tstalks /Ears 19 25 2 tstalks /Ears 25 28 3 tstalks /Ears 22 30 4 tstalks /Ears 20 16 5 ■[Stalks /Ears 23 90 6 tstalks (Ears 26 33 7 \Stalks /Ears 29 38 8 ■[Stalks /Ears 30 OO 9 tstalks /Ears 27 24 10 [Stalks « Favoring the cross: Ears, 7 out of 10; stalks, 5 out of 10. Average weight of ears per stalk produced by the female parent, 0.47 pound; by the cross, 0.48 pound. Average weight of stover per stalk produced by female parent, 0.73 pound; by the cross, 0.71 pound. Increased yield of cross over the female parent: Grain, 2 per cent; stover, 2 per cent. •Favoring the cross: Ears, 6 out of 10; stalks, 5 out of 10. Average weight of ears per stalk produced by the female parent, 0.49 pound; by the cross, 0.51 pound. Average weight of stover per staLk produced by female parent, O.SO pound; by the cross, 0.82 pound. Increased yield of cross over the female parent: Grain, 3 per cent; stover, 2 per cent. 218 TESTS AT STATESBORO, GA. 53 Table XVI. — Yield record of 11 varieties of corn and their crossed progeny tested at atatesboro, Ga.— Continued. Marlboro Proufic 9 x Kodqers White Dent (/.i Num- Seed ber ear of No. perfect hills. 1 25 2 26 3 22 4 25 5 22 6 21 7 24 8 21 9 18 10 15 Kind of product. /Ears.. \Stalks. IEars.. Stalks, Ears.. Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks iEars.. Stalks Ears.. Stalks /Ears.. \Stalks /Ears.. \Stalks Weight of product (pounds). Total. OriKi- nal. 14.50 26.50 12.50 21.00 11.50 19.75 14.50 26.25 12.00 21.00 11.00 18.50 10.75 19.00 12.00 22.00 10.50 17.00 7.50 12.75 Cross. 13.25 25.25 14.00 25.00 12.00 23.25 15.00 26.75 13.00 23.00 12.00 21.00 13.50 23.50 11.75 19.50 10.50 17. 25 10.00 15.75 Per stalk. Origi- nal. 0.58 1.06 .48 .81 .52 .90 .58 1.05 .55 .95 .52 .88 .45 .79 .57 1.05 .58 .94 .50 .85 Cross. 0.53 1.01 .54 .96 .55 1.06 .60 1.07 .59 1.05 .57 1.00 .56 .98 .56 .93 .58 .96 .67 1.05 Differ- ence. -0.05 - .05 .06 .15 .03 .16 .02 .02 .04 .10 .05 .12 .11 .19 - .01 - .12 .00 .02 .17 .20 Per cent of differ- ence > - 9 - 5 12 19 4 18 3 2 8 10 9 14 26 24 - 2 -11 0 1 33 24 Number of ears produced. Origi- nal. 33 28 '29 37 '27 28 '29 29 '22 is Cross. 28 '27 '27 '27 '28 '23 '28 '22 '26 "22 MosBY Prolific 9 X Marlboro Prolific J^ 1 25 2 20 3 19 4 19 5 20 6 16 7 17 8 13 9 17 10 23 /Ears... \S talks., /Ears... \Stalks. /Ears... \Stalks. /Ears... \Stalks. /Ears... \Stalks. /Ears... \S talks. /Ears... \S talks. iEars... Stalks. Ears... Stalks. /Ears... \S talks. 12.00 21.00 12.50 20.00 8.00 14.50 8.75 14.25 9.00 15.50 7.75 13.75 8.25 14.00 8.00 13.75 8.75 15.00 9.00 18.00 13.75 22.75 13.00 20.00 10.00 16.50 9.50 15.50 11.75 18.25 9.26 14.75 9.00 14.00 8.75 15.25 9.00 14.00 10.00 18.00 0.48 .84 .63 1.00 .42 .76 .46 .75 .45 .78 .48 .86 .49 .82 .62 1.06 .51 .88 .39 .78 0.55 .91 .65 1.00 .53 .87 .50 .82 .59 .91 .58 .92 .53 .82 .67 1.17 .53 .82 .43 .78 0.07 .07 .02 .00 .11 .11 .04 .07 .14 .13 .10 .06 .04 .00 .05 .11 .02 - .06 .04 .00 15 8 4 0 25 14 9 9 31 18 19 7 9 0 9 11 3 - 7 11 0 35 34 34 30 2^1 25 20 20 22 2(i 19 18 19 18 18 19 18 23 23 25 Average weight of ears per stalk produced by Average weight of stover per stalk produced Increased yield of cross over the female parent: 1 Favoring the cross: Ears, 7 out of 10; stalks, 8 out of 10. the female parent, 0.53 pound; by the cross, 0.57 pound, by female parent, 0.93 pound; by the cross, 1.01 pounds. Grain, 7 per cent; stover, 8 per cent. „ ■, . 2 Favoring the cross: Ears, 10 out of 10; stalks, 6 out of 10. Average weight of ears per stalk produced by the female parent, 0.49 pound; by the cross, 0.55 pound. Average weight of stover per stalk pro- duced by female parent, 0.S5 pound; by the cross, 0.89 pound. Increased yield of cross over the female parent: Grain, 13 per cent; stover, 6 per cent. 218 54 Table XVI. CROSSBREEDING CORN. Yield record of 11 varieties of corn and their crossed progeny tested at Statesboro, Ga. — Continued. MOSBY PEOLIFIC $ X RODGERS WHITE DENT cf.l Niun- Seed ber ear of No. perfect hills. 1 18 2 17 3 22 4 18 5 22 6 20 7 22 8 23 9 18 10 25 Kind of product. /Ears.. \Stalks I Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks /Ears.. \Stalks Weight of product (pounds). Total. Origi- nal. 6.75 13.00 6.75 11.25 8.75 14.75 9.00 14.50 8.50 14.25 8.50 14.75 10.25 17.25 10.25 19.50 10.00 16.75 10.75 20.25 Cross. 10.00 15.75 8.25 12.25 12.50 20.25 11.50 18.50 11.00 17.50 11.50 18.00 12.75 20.50 13.00 21.75 10.75 18.50 13.75 23.25 Per stalk. Origi- nal. 0.38 .72 .40 .66 .40 .67 .50 .81 .39 .65 .43 .74 .47 .78 .45 .85 .56 .93 .43 .81 Cross. 0.56 .88 .49 .72 .57 .92 .64 1.03 .50 .80 .58 .90 .58 .93 .57 .95 .60 1.03 .55 .93 Differ- ence. 0.18 .16 .09 .06 .17 .25 .14 .22 .11 .15 .15 .16 .11 .15 .12 .10 .04 .10 .12 .12 Per cent of differ- ence. Number of ears produced. Origi- nal. 48 21 22 9 43 37 28 28 29 23 35 22 24 19 27 12 8 10 28 15 25 'is' '27' '21' '22' '23' '25' 'si' '22' '28' Cross. 23 '26 "si '22 '27 '27 "27 '26 "22 '29 Native of Statesboeo 9 X Maklboro Proufic d^ 21 20 7 23 21 13 15 /Ears 13.25 21.25 10.75 17.50 3.25 5.50 11.25 18.75 9.00 15.25 7.00 11.00 7.25 11.25 6.00 10.00 7.75 13.25 6.75 9.75 12.75 20.00 11.50 18.00 3.25 5.00 12.25 21.50 10. 50 17.75 6.75 11.50 7.00 11.00 6.25 10.50 10.00 15.25 7.00 10.50 0.63 1.01 .54 .88 .46 .79 .49 .82 .43 .73 .54 .85 .48 .75 .60 1.00 .43 .74 .52 .75 0.61 .95 .58 .90 .46 .71 .53 .93 .50 .85 .52 .88 .47 .73 .63 1.05 .,56 .85 .54 .81 -0.02 - .06 .04 .02 .00 - .08 .04 .11 .07 .12 - .02 .03 - .01 - .02 .03 .05 .13 .11 .02 .06 -4 - 6 7 3 0 - 9 9 15 17 16 - 4 5 - 3 - 2 4 5 29 15 4 8 22 23 1 \Stalks /Ears .... 21 22 2 \Stalks /Ears 7 8 3 \Stalks /Ears 24 25 4 \Stalks /Ears 22 21 5 \Stalks 6 /Ears Istalks 14 14 /Ears 15 16 7 \Stalks /Ears 11 15 8 10 18 13 \Stalks /Ears 18 19 9 ^Stalks /Ears 13 14 10 \Stalks 1 Favoring the cross: Ears, 10 out of 10; stalks, 10 out of 10. Average weight of cars per stalk produced by the female parent, 0.44 pound; by the cross, 0.56 pound. Average weight of stover per stalk produced by female parent, 0.76 pound; by the cross, 0.91 pound. Increased yield of cross over the female parent: Grain, 28 per cent; stover, 19 per cent. 2 Favoring the cross: Kars, 6 out of 10; stalks, 7 out of 10. Average weight of ears per stalk produced by the female parent, 0.51 pound; by the cross, 0.54 pound. Average weight of stover per stalk produced by female parent, 0.83 poimd; by the cross, 0.88 pound. Increased yield of cross over the female parent: Grain, 6 per cent; stover, 0 per cent. 218 TESTS AT STATESBORO, GA. 55 Table XVI. — Yield record of 11 varieties of corn and their crossed progeny tested at ^tatesboro, Ga.— Continued. Native of Statesboro ? X Rodgebs White Dent cT-' Num- ber of perfect hills. Kind of product. Weight of product (pounds). Per cent of difler- ence. Number of ears Seed ear No. Total. Per stalk. produced. Origi- nal. Cross. Origi- nal. Cross. Differ- ence. Origi- nal. Cross. 15 18 11 12 17 11 18 19 22 21 fEars 9.50 15.50 10.75 18.75 7.25 12.25 7.00 12.25 9.50 16.50 5.50 11.50 8.00 15.00 8.25 14.50 7.75 14.00 9.75 14.25 7.50 12.75 11.00 18.50 7.25 12.25 6.00 9.50 10.50 17.50 6.00 10.50 8.25 14.25 10.50 18.75 12.00 20.50 9.75 16.75 0.63 1.03 .60 1.04 .60 1. 11 .58 1.02 .56 .97 .50 1.05 .44 .83 .43 .76 .35 .64 .46 .68 0.50 .85 .61 1.03 .66 1.11 .50 .79 .62 1.03 .55 .95 .46 .79 .55 .99 .55 .93 .40 .80 -0.13 - .18 .01 - .01 .00 .00 - .08 - .23 .06 .06 .05 - .10 .02 - .04 .12 .23 .20 .29 .00 .12 -21 -18 2 - 1 0 0 -14 -22 11 6 9 - 9 3 - 5 27 29 55 46 0 18 17 15 1 1 Stalks /Ears 19 22 2 1 Stalks JEars 12 14 3 1 Stalks .. fEars 12 12 4 1 Stalks /Ears 17 17 5 Istalks /Ears 12 11 G 1 stalks /Ears 18 20 7 Istalks /Ears 19 19 8 istalks (Ears 23 22 9 Istalks /Ears 21 21 10 Istalks RODGEES White Dent 9 X Marlboro Prolific c?-^ 1 18 2 22 3 19 4 21 5 25 6 17 7 22 8 17 9 12 10 17 /Ears.. \Stalks, /Ears., tstalks, /Ears.. \Stalks, /Ears . . \Stalks, /Ears.. \Stalks /Ears.. \Stalks iEars . . Stalks Ears.. Stalks /Ears.. \Stalks /Ears.. \Stalks 10.00 15.50 11.50 10.75 9.75 15.75 12.00 17.50 11.75 18.25 7.50 12.25 10.00 15.75 9.25 14.50 5.25 8.00 8.50 13.50 10.75 16. 75 11.00 17.00 12.00 19.00 11.75 18.75 13.00 20.50 10.25 15.25 10.50 16.75 9.25 14.75 6.75 11.00 9.50 15.00 0.56 .86 .52 .76 .51 .83 .57 .83 .47 .73 .44 .72 .45 .72 .54 .85 .44 .67 .50 .79 0.60 .93 .50 .77 .63 1.00 .56 .89 .52 .82 .60 .90 .48 .76 ..54 .87 .56 .92 .56 .88 0.04 .07 - .02 .01 .12 .17 - .01 .06 .05 .09 .16 .18 .03 .04 .00 .02 .12 .25 .06 .09 8 - 4 1 23 21 - 2 7 11 12 37 24 5 6 0 2 28 38 12 11 18 26 '22' 28 '25' 17 '22' 17 "is "19 24 '22 23 '27 '36 ig "22 ig 14 '26 1 Favoring the cross: Ears, 6 out of 10; stalks, 4 out of 10. Average weight of ears per stalk produced by the female parent, 0.51 pound; by the cross, 0.54 pound. Average weight of stover per stalk produced by female parent, 0.88 pound; by the cross, 0.92 pound. Increased yield of cross over the female parent: Grain, 7 per cent; stover, 5 per cent. 2 Favoring the cross: Ears, 7 out of 10; stalks, 10 out of 10. Average weight of ears per stalk produced by the female parent, 0.50 pound; bv the cross, 0.55 pound. Average weight of stover per stalk pro- duced by female parent, 0.78 pound; "by the cross, 0.87 pound. Increased yield of cross over the female parent: Grain, 10 per cent; stover, 12 per cent. 218 56 CROSSBREEDING CORN. Table XVI. — Yield record of 11 varieties of corn and their crossed progeny tested at Statesboro, Ga. — Continued. RoDGEES White Dent 9 X Rodgers White Dent 8 34 33 — 5 1 10 11 39 41 9 3 0 7 15 9 26 35 - 9 -11 Number of ears produced. Origi- nal. 17 24 20 23 22 26 10 21 20 20 Cross. 17 24 19 19 26 21 16 21 21 19 TiNDAL 9 X Marlboro Prolific c?-' 1 22 2 19 3 23 4 21 5 18 6 15 7 24 8 17 9 18 10 24 /Ears.... \Stalks... /Ears.... tstalks... /Ears tstalks... /Ears tstalks... /Ears tstalks... /Ears tstalks... /Ears.... IStalks... /Ears.... tstalks... /Ears tstalks... /Ears tstalks. . . 11.75 17.50 9.50 14.50 12.00 18.00 11.00 17. 75 9.50 16.25 7.50 12.50 15.00 23. 75 9.00 14.00 9.00 13. 50 12. 00 18.00 12.00 18.75 9.50 14.75 12.00 18.75 12.25 19.25 8.25 13.50 7.50 12.00 11.25 18.00 9.75 15.00 8.75 13.50 12.25 18.75 0.53 .80 .50 .76 .52 .78 .52 .85 .53 .90 .50 .83 .63 .99 .53 .82 .50 .75 .50 .75 0.55 .85 .50 .78 .52 .82 .58 .92 .46 .75 .50 .80 .47 .75 .57 .88 .49 .75 .51 .78 0.02 .05 .00 .02 .00 .04 .06 .07 -.07 -.15 .00 -.03 -.16 -.24 .04 .06 -.01 .00 .01 .03 2 7 0 2 0 4 11 8 -13 -17 0 - 4 -25 -24 8 7 - 3 0 2 4 30 27 33 30 '26 19 "37' '21' 19 '33' 34 '25 '32 '33 '23 "ie '26 '2! 19 26 1 Favoring the cross: Ears, 7 out of 10; stalks, 9 out of 10. Average weight of ears per stalk produced by the female parent, 0.52 pound; by the cross, 0.59 pound. Average weight of stover per stalk produced by female parent, 0.8.5 pound; by the cross, 0.96 pound. Increased yield of cross over the female parent: Grain, 13 per cent; stover, 13 percent. 2 Favoring the cro.s.s: Ears, 4 out of 10; stalks, C out of 10. .\verage weight of ears per stalk produced by the female parent, 0..53 pound; by the cross, 0.51 pound. .Vverago weight of stover per stalk produced by female parent, 0.82 pound; by the cross, O.Sl povmd. Increased yield of cross over the female parent: Grain, —3 per cent; stover, —2 per cent. 218 TESTS AT STATESBORO, GA. 59 Table XVI. — Yield record of 11 vurieiUs of corn and their crossed progeny tested at Statesboro, Ga. — Continued. TlNDAL 9 X RODOERS WHITE DENT cf •' Num- ber of perfect hills. Kind of product. Weight of product (pounds). Per cent of differ- ence. Number of ears Seed ear No. Total. Per stalk. produced. Origi- nal. Cross. Origi- nal. Cross. Differ- ence. Origi- nal. Cross. 12 20 24 20 16 23 16 13 13 18 /Ears 6.00 9.25 9.50 15.75 10.25 15.00 9.75 15.25 7.50 11.75 11.50 18.75 9.25 14.00 7.00 10.50 6.50 10.25 10.00 14.25 5.75 9.25 10.75 17.25 12.25 19.50 10.50 16.00 8.00 12.25 14.00 21.00 8.00 13.00 7.50 11.25 7.75 10.50 9.25 14.75 0.50 .77 .48 .79 .43 .63 .49 .76 .47 .73 .50 .82 .58 .88 .54 .81 .50 .79 .56 .79 0.48 .77 ..54 .86 .51 .81 .53 .80 .50 .77 .61 .91 .50 .81 .58 .87 .60 .81 .51 .82 -0.02 .00 .06 .07 .08 .18 .04 .04 .03 .04 .11 .09 - .08 - .07 .04 .06 .10 .02 - .05 .03 - 4 0 13 10 20 30 8 5 7 4 22 12 -14 - 7 7 7 19 2 - 8 4 18 14 I IStalks /Ears 26 22 2 IS talks (Ears 29 28 3 IStalks /Ears 26 22 4 IStalks /Ears . 17 18 5 IStalks (Ears 27 32 6 IStalks (Ears 22 16 7 IStalks (Ears 14 13 8 IStalks (Ears 15 14 9 IStalks (Ears 25 22 10 IStalks Whelchel ? X Marlboro Prolific cf-^ 1 9 2 8 3 7 4 24 5 17 6 20 7 12 8 6 9 18 10 22 /Ears.. \Stalks. (Ears.. \Stalks. /Ears . . \Stalks. /Ears.. \Stalks /Ears . . IStalks /Ears . . \Stalks /Ears . , \Stalks /Ears . , \Stalks /Ears . , \Stalks /Ears . , IStalks 4.25 8.00 5.00 8.75 4.75 8.25 15.75 26.75 9.75 16.00 12.50 25.00 9.00 16.00 4.50 8.00 11.75 20.75 15.50 27.50 5.25 9.50 4.00 8.25 4.25 7.50 15.75 27.75 10.75 19.00 14.75 25.50 7.75 13.00 5.00 7.75 14.00 23.75 16.50 27.50 0.47 .89 .63 1.09 .68 1.18 .66 1.11 .57 .94 .63 1. 0.58 1.06 .50 1.03 .61 1.07 .66 1.16 .63 1.12 .74 1.28 .65 1.08 .83 1.29 .78 1.32 .75 1.25 0.11 .17 -.13 -.00 -.07 -.11 .00 .05 .06 .18 .11 .03 -.10 -.25 .08 -.04 .13 .17 .05 .00 24 19 -20 - 6 -10 - 9 0 4 10 19 18 2 -14 -19 11 - 3 19 14 6 0 9 9 9 10 8 7 26 29 17 17 21 26 12 12 7 9 19 23 22 29 1 Favoring the cross: Ears, 7 out of 10; stalks, 8 out of 10. Average weight of ears per stalk produced by the female parent, 0.50 pound; by the cross, 0.54 pound. Average weight of stover per stalk produced by female parent, 0.77 pound; by the cross, 0.83 poimd. Increased yield of cross over the female parent: Grain, 7 per cent; stover, 7 per cent. * Favoring the cross: Ears, 6 out of 10; stalks, 5 out of 10. Average weight of ears per stalk produced by the female parent, O.aS pound; by the cross, 0.69 pound. Average weight of stover per stalk produced by female parent, 1 .15 pounds; by the cross, 1.19 pounds. Increased yield of cross over the female parent: Grain, 6 per cent; stover, 3 per cent. 218 60 Table XVL- CROSSBREEDING CORN. Yield record of 11 varieties of corn and their crossed progeny tested at iitatesboro, Ga. — Continued. WiLUAMsoN 9 X Marlboro Prolific cf.' Num- Seed ber ear of No. perfect hUls. 1 11 2 14 3 13 4 13 5 17 , 6 17 Kind of product. /Ears . . \Stalks J Ears . . \Stalks I Ears.. \Stalks (Ears. . \Stalks I Ears.. \Stalks lEars.. IStalks Weight of product (pounds). Total. Origi- Cross nal. ^™''^- 4.50 7.00 0.50 11.75 7.25 11.75 6.25 10.25 0..50 10.50 8.50 13.00 5.00 8.50 9.00 13.75 7.00 11.50 6.50 9.75 10.00 17.25 8.50 13.00 Per stalk. Origi- nal. Cross. 0.41 .04 .40 .84 .50 .90 .48 .79 .38 .62 .50 .76 0.45 .77 .64 .98 .54 .88 .50 . 75 .59 1.01 .50 .76 Differ- ence. 0.04 .13 .18 .14 -.02 -.02 .02 -.04 .21 .39 .00 .00 Per cent of differ- ence. 11 21 3S 17 -3 -2 4 -5 54 64 0 0 Number of ears produced. Origi- nal. 11 16 'i3 14 "u 'is AVILLIAMSON ? X EODGERS WHITE DENT cf .^ Cross. 11 "is 'i5 i5 ig 'i? 1 18 2 22 3 18 1 4 23; 5 14 ! 6 16 7 6 S 8 9 15 0 15 1 J Ears 8. 50 \Stalks 15.50 /Ears 10. 75 tstalks 18.50 (Ears 10.50 \Stalks 16.75 /Ears 11.50 \Stalks 20.25 (Ears 6.75 \Stalks ■< 11.25 /Ears 7.00 IStalks 11.75 (Ears 3.75 \Stalks 6.75 (Ears 4.25 \Stalks 6.75 (Ears 7.75 \Stalks 13.00 (Ears 7.50 IStalks 12.00 9.50 17.50 14.75 25.75 11.00 17.50 14. 50 26.00 7.50 12.50 9.00 15.50 3.25 5. .50 5.00 8.25 8.00 13.00 6. 75 12.00 0.47 .86 .49 .84 .58 .93 .50 .88 .48 .80 .44 .73 .63 1.13 .53 .84 .52 .87 .50 .80 0.53 .97 .67 1.17 .61 .97 .63 1.13 .54 .89 .56 .97 .54 .92 .63 1.03 .53 .87 .45 .80 0.06 .11 .18 .33 .03 .04 .13 .25 .06 .09 .12 .24 -.09 -.21 .10 .19 .01 .00 -.05 .00 12 13 37 39 5 4 26 28 11 11 29 32 -13 -19 18 22 3 0 10 0 19 21 22 28 19 20 26 22 14 15 16 16 7 6 9 8 16 15 15 15 1 Favoring the cross: Ears, 4 out of 6; stalks, 3 out of 6. Average weight of ears per stalk produced bv the female parent, 0.46 pound; by the cross, 0.54 pound. Average weight of stover per stalk produced by female parent, 0.76 poimd; by the cross, 0.87 pound. Increased yield of cross over the female parent: Grain, 16 percent; stover, 14 per cent. 2 Favoring the cro.ss: Ears, 8 out of 10; stalks. 7 out of 10. Average weight of ears per stalk produced by the female parent, 0..')0 pound; by the cro.ss, 0..58 potmd. Average weight of stover per stalk produced by female parent, 0.S5 pound; by the cross, 0.99 poimd. Increased yield of cross over the female parent: Grain, 14 per cent; stover, 16 per cent. In Table XVII a comparison of the effect of crossing is made between the varieties as a whole, when crossed by Marlboro Prolific and when crossed by Rodgers White Dent. The percentage of increase or decrease in yield of the cross is given, and also the number of rows out of 10 in which the production of the crossed ears w^as greater tlian that of the original 2-year-old seed of the female parent grown in the same hills with the cross. 218 TESTS AT STATESBORO, GA. 61 Table XVII. — Summary of the 10 ears of each variety tested with their crossed progeny. Marlboro Prolific sire. Rodgers White Dent sire. Female variety. Increase of cross over 1908 seed of female parent. Rows favoring the cross. Increase of cross over 1908 seed of female parent. Rows favoring the cross. Ears. Stalks. Ears. Stalks. Ears. Stalks. Ears. Stalks. Akirich Perfection Percent. 12 8 3 13 6 10 4 12 - 3 16 Per cent. - 6 2 2 6 6 12 3 10 - 2 14 6 7 6 10 6 7 6 6 4 14 5 4 5 6 7 10 3 6 6 13 Percent. 10 2 7 28 7 - 8 13 13 7 14 Per cent. 15 - 2 8 19 5 - 9 17 13 7 16 7 7 7 10 6 3 7 7 7 8 9 Cocke Prolific 5 Marlboro Prolific 8 Mosbv Prolific 10 Native of Statesboro 4 Rodgers White Dent 3 Sanders Prolific 8 station Yellow 9 Tindal 8 Williamson 7 General results 7 4 6.9 6.1 9 9 6.9 7 1 Only six rows considered. Table XVII shows that when crossed with Marlboro Prolific all but one variety (Tindal) gave a gain in ears, and all but two varieties gave a gain in stover. Wlien crossed with Rodgers Wliite Dent all varieties except the sire variety itself gave a gain in ears, and only two gave a loss in stover. SOME CROSSES SUPERIOR TO EITHER PARENT. Since the yields of the crosses are compared only with the female parent, it might be concluded that this general higher yield of the crosses is probably due to the still greater productiveness of the male parent. This conclusion, however, is not supported in the cases where Marlboro Prolific and Rodgers Wliite Dent serve as females in the experiment. In both instances the resulting cross produced better than its female parent and since Rodgers Wliite Dent is more productive than Marlboro Prolific, as shown in Table XVII, the cross in which Rodgers Wliite Dent served as female must be con- sidered more productive than either parent. In Table XVIII is shown the average ranking of the varieties according to their productiveness in 1910 in the test plats at States- boro, Ga., where each variety was grown in the same hills w^ith its crossed progeny. Table XVIII. — Arrangement of varieties of corn in the order of their productiveness, as indicated by the average yield per stalk when groion in hills with their crosses. Name of variety. Sanders Prolific Aldrlch Perfection. . Rodgers White Dent Tindal Marlboro Prolific Ears per Average stalk. rank. Pounds. 0.535 1 .53 2a .53 26 .515 3 .51 4a Name of varietv. Ears per stalk. Native of Statesboro Station Yellow Cocke Prolific Williamson Mosby Prolific Pounds. 0.51 ,51 .49 .48 .465 Average rank. 46 4c 5 6 7 218 62 CROSSBREEDING CORN. It will be seen that seven varieties equal or excel Marlboro Pro- lific. Wlien these seven varieties are crossed with Marlboro Prolific as sire six out of the seven first-generation crosses exceed the Marl- boro Prolific in grain production, and five in stover production. It will also be seen that two varieties equal or excel Rodgers White Dent. Wlien these two varieties are crossed with Rodgers Wliite Dent as sire both of the first-generation crosses exceed the Rodgers White Dent in grain and stover production. It will thus be seen that out of the 20 crosses made 8 have given grain yields greater than the better parent, and 7 have given stover yields greater than the better parent. RELATION OF THE PRODUCTIVITY OF THE CROSSES TO THE PRODUCTIVITY OF THE PURE STRAINS. It is a striking point in connection with the foregoing table that aU those female varieties giving more productive crosses than either parent are grouped at one end — the upper end — of the ranking list for production and with but one break in the rank. None fall below fourth in production in a total ranking of seven. With one excep- tion the varieties that can not be said to have given advantageous crosses with either sire are grouped at the other or lower end of the ranking list. Omitting Marlboro Prolific and Rodgers Wliite Dent, nine other varieties are crossed by each of these sires. In six out of the nine comparisons the crosses with Rodgers Wliite Dent are more productive than those mth Marlboro Prolific. In view of these points and the fact that Rodgers Wliite Dent is more productive than Marlboro Prolific it is found that the pro- ductiveness of both parents seems to stand out clearly as a factor in influencmg high yield in first-generation crosses. The Tindal variety, however, is a striking exception to this seem- ing tendency. The rank of this variety is third in productiveness, but when crossed by Marlboro Prolific its yield was actually less than its poorest producing parent; and when crossed by Rodgers White Dent the cross was less productive than that sire. Because of this exception, this apparent tendency can not be relied upon as a guide in the selection of suitable varieties for practical crossing. ADAPTATION AS A FACTOR IN THE PRODUCTION OF HIGHER YIELDS THROUGH CROSSING. As the difference between the lowest and the highest producers is less than 5 bushels per acre, it would seem that it might be ques- tionable to dicuss this subject with the data at hand. In justice to the subject, however, it should be stated that the appearance of the corn produced indicated more variabihty in adaptation than do the weights. 218 TESTS AT STATRSBORO, GA. 63 It is interesting to note in this connection that the variety Mosby Prohfic is farthest from home, that it has been carried to a more radically different soil than any of the other varieties, and that it is ranked lowest in yield and failed to give a practical cross. Cocke Prolific is the next farthest from home, ranks third from the bottom of the list, and was impractical for crossing with either Marlboro Prolific or Rodgers White Dent. The Williamson corn ranks next to Mosby Prolific; as it had been given considerable selection at home for years, it is reasonable to suppose that its low yield is due to poor adaptation. It is thus seen that three out of the four varieties that were imprac- tical as crosses with either of the two sires were also poorly adapted to the conditions at Statesboro. The Tindal variety again stands out as an exception. INFLUENCE OF SEASONAL DIFFERENCES. In 1909, while the crosses for this test were being grown, a careful comparison of the varieties was made. The season was different from that of 1910, and the effect is clearly shown by the ranking obtained at that time. The ranking for 1909 was: First Tindal. Second Station Yellow. Third Native of Statesboro. Fourth Rodgers White Dent. Fifth Marlboro Prolific. Sixth Williamson. Seventh Mosby Prolific. Eighth Aldrich Perfection. Ninth Cocke Prolific. Tenth Sanders Prolific. Apparently the difference between the two seasons has resulted in changing Sanders Prolific from last to first in rank and Aldrich Per- fection from eighth to second. The first year less difference in pro- duction was shown between the two sire varieties than was shown the second year. In 1909 Mosby Prolific (poorest in 1910) ranked better than Aldrich Perfection (second in 1910). Tindal ranked high both years. The differences showai by the two tests are radical, but hardly more than is frequently found in variety tests of more than one year. If, as has been previously indicated, there is usually a relation between high yield and adaptation and the advantageous crossing of corn, then it would seem that seasonal differences may play an important part. INFERENCES DRAWN FROM THE FOREGOING DATA. From these tests it would seem that the productivity of first- generation crosses is usually correlated to the productivity of the parent varieties, and the yield of the parent varieties is largely dependent upon their adaptation to the location and the season during which the test is made. 218 64 CROSSBREEDING CORN. As seasonal differences have a marked effect upon the comparative production of varieties the success of a cross one season may be found fleeting if continued. The fact that the variety Tindal in its adverse performance toward crossing has rather emphatically ignored all the influences of rank and adaptation that seem to govern other varieties may indicate that advantageous exceptions may also be found; but whatever further investigation may demonstrate, present knowledge indicates that the economic increasing of corn yields by means of crossing is attended with many complexities. GENERAL CONSIDERATION OF ALL THE TESTS. INDICATIONS OF INTERMEDIACY. As the varieties crossbred at the various points are varieties that have met with general favor as grain producers, the characters of the male and female parents of each cross are not radically different, and consequently any intermediacy of a cross is not as apparent as it might be if the parents were much unlike. However, in many instances intermediacy between the two parents was observed regard- ing various characters; such as productiveness, height of stalk, length of growing season, and percentage of moisture. Averages of many crosses usually indicate intermediacy, because exceptions in one direction from the median points are offset by exceptions in the other direction, but under the conditions of these and other tests of this nature so few instances have been shown in which the first-generation crosses produced less than the average of the two parents as to indicate that the average productiveness of first-generation corn crosses is usually above the average of the parents. It may be that this indication ^\^ll not be found entirely due to advantages regarding adaptation, age of seed, self-fertilization, etc., that most of the reported tests ^ have given to the first-generation 1 Beal, W. J. Reports, Michigan Board of Agriculture, 1876, 1877, 1S81, and 1882. Ingersoll, C. L. Seventh and Ninth Annual Reports of Purdue University, 1881 and 1883. Sanborn, J. W. Indian Com. Agriculture of Maine, Thirty-third Annual Report, Maine Board of AgrL culture, 1889-90. Kellerman, W. A., and Swingle, W. T. Crossed Varieties of Corn. Bulletin 17, Kansas Agricultural Experiment Station, 1890. McCluer, G. W. Com Crossing. Bulletin 21, Illinois Agricultural Experiment Station, 1892. Morrow, G. E., and Gardner, F. D. Bulletins 25 and 31, Illinois .Vgricultural Experiment Station, 1893 and 1S94. Webber, H. J., and Swingle, W. T. Hybrids and their Utilization in riant Breeding. Yearbook, U. S. Dept. of Agriculture, for 1897. Vanattor, Phares O. Annual Report, ^■i^ginia Agricultural Experiment Station, 1906. ShuU, G. H. The Composition of a Field of Com. Report, American Breeders' Association, vol. 4, 1908 Also A Pure Line Method in Com Breeding. Report, same, vol. 5, 1909. East, E. M. The Distinction between Development and Heredity In Inbreeding. American Natu- ralist, vol. 43, No. 507, 1909. Collins, G. N. The Value of First-Generation Hybrids in Com. Bulletin 191, Bureau of Plant Industry, U. S. Dept. of Agriculture, 19in. Increased yields of Corn from Hybrid Seed. Yearbook, U. S. Dept. of Agriculture, for 1910. Hays, II. K., and East, E. M. Improvement in Corn. Bulletin 168, Conneoticut Agrlcultiiral Experiment Station, 1911. 218 GENERAL, CONSIDERATION OF ALT. THE TESTS, 65 crosses, and that further work witli all conditions more nearly equalized will demonstrate a general tendency for first-generation crosses to pro- duce better than the average of the parents. Such a general tendency might be due to prepotency of the higher yielding parent. It is more profitable to grow the higher yielding parent except in cases in which the first-generation cross produces better than either parent. Since some first-generation crosses are more productive and some are less productive than their better parent, the greatest benefit can be obtained by planting such as may be found more productive than the highest yielding variety of a community. PERCENTAGE OF MOISTURE IN SHELLED GRAIN OF CROSSES AND PARENT VARIETIES. Because of care in allowing the ears of all varieties to dry thor- oughly before yields were weighed it has not been necessary to calcu- late corrections for moisture content except in the Maryland tests. The moisture content of shelled grain from a large number of ears of each variety at each point was determined by the Office of Grain Stand- ardization of the Bureau of Plant Industry. Regarding this char- acter, averages as given in Table XIX show the first-generation crosses to be intermediate between the parents. Table XIX. — Average percentage of moisture in shelled grain of crosses and parent varieties on dates when yields were weighed. Tests. Maryland California Texas Georgia General average Female parents. 27.29 10.22 12. 39 15.40 16.33 Male parents. 28.77 11.74 11.45 15.01 16.74 Average of both parents. 28.03 10.98 11.92 15.21 16.54 First-gen- eration crosses. 28.32 10.90 12.13 15.00 16.59 UNRELIABILITY OF AVERAGES FOR SPECIFIC INSTANCES. With investigations of this nature the investigators as well as the readers are desirous that the work should discover some law of nature. However, the development and evolution of plants furnish so many exceptions and variations to even general laws that it is impossible to foretell the effects of crossbreeding particular varieties by the effects secured previously from crossbreeding other varieties. T^-pes, varieties, strains, ears, and even kernels of corn contain in their lineage such complexit}^ of structure and characters that it is not surprising that this work, necessarily of a prehminary nature, should unfold more problems than it solves. The results are interesting because they contain evidence in sup- port of various theories, but the chief value of the work is its indi- 218 66 CROSSBREEDING CORN. cation of what can be accomplished in the field of research and more especially in estabHsliing methods of producing high-j-ielding seed corn. The influences that show with the greatest uniformity in these tests are those of acchmatization and adaptation. The results given here of these influences will be combined in a future publication with results obtained in other localities showing the effects on maize of acclimatization and adaptation. In studj^ing the effects attributable to crossbreeding it is necessary to recognize the effects due both to acchmatization and to adaptation. The distinction between the effects of acclhnatization and of adaptation is brought out in the tests of identically the same lots of seed in Maryland and in Cali- fornia. In Maryland, because of their acclimatization and adaptation some varieties produced much better than others of the same growing period which were brought from distant States. None of these varieties were acclimated to Cahfornia conditions, though some of the earliest maturing, which were least productive in Maryland, were most productive in California. Their early maturity proved an adaptation which enabled them to escape the later and drier part of the summer. In Texas, varieties that have been subjected for years to practically the same chmatic conditions indicate different degrees of adaptation to clay soils and to sandy soils. Tests of this nature thus far reported indicate that first-generation crosses usually produce better than the average of the two parents. It is not certain that this is entirely due to the advantages that these tests have given to the crosses regarding age and vitality of seed, or to the year of adaptation and selection incident to growing the crossbred seed under the same environment in which the test of productiveness was afterwards made, but to which the parent varieties were not adapted. If further tests should show that with all conditions equalized there still exists a tendency for first-generation crosses to produce betfer than the average of the two parents, it might be taken as an indication that the higher yielding parent is usually prepotent. A production better than the average of the two parents, unless it be better than the production of either parent, would furnish no practical method of originating strains superior to those already existing, except in cases in which the crossing might originate strains that combine or nick better than previously existing strains. When all influencing factors, such as age and maturity of seed, acchmatiza- tion, and adaptation are equal, and the first-generation cross is more productive than either parent, it is a clear instance in which a prac- tical advantage is derived by crossbreeding. Variations found to apply to varieties are also found to apply to different ears within a variety when they are crossbred and tested separately — in other words, some ears arc crossed with another 218 GENERAL CONSTDEEATTON OF ATJ. TTIE TESTS. 67 variety advantageously and some disadvantagcously, tliough in general there is a tendency for the difl'erent ears of a variety to respond similarly to the crossing. Another line of work being con- ducted by the Office of Corn Investigations indicates that what has just been said about the crossing of one variety with another also applies to the crossbreeding of individual plants within a variety. Just as certain pairs of varieties combine or nick advantageously, while other pairs nick disadvantagcously, so some pairs of individual plants nick advantageously, while other pairs nick disadvantagcously. Tliis shows the results obtained by crossing two varieties without reference to individual plants to be but an average of the results that would be obtained by crossing many individual plants of those varieties. The average results may be an improvement over either parent and still fall short of what could be obtained by restricting the crossing to the individuals that nick most advantageously. In connection with this consideration of crossbreeding, it is inter- esting to note that such varieties as Selection 119, Selection 160, and Chisholm, wliich are among the most profitable varieties for their respective localities, have not been crossbred or mixed with other varieties for liiany years. The same can be said of leading strains of corn of other localities, and their merits are doubtless largely due to effects of selection, acclimatization, and adaptation. The results of these tests show that with corn some first-generation crosses are more productive than either parent, that some are inter- mediate between the two parents in productiveness, and that some are less productive than either parent. They also show that the determination of the particular first-generation crosses that can be most profitably grown is attended with so many complexities that careful tests must be made in a locality before the farmers of that locality can be intelUgently advised whether it is to their interest to continue planting a pure-bred strain, or to plant a first-generation cross of certain strains. In crossbreeding corn for practical results it seems the duty of State experiment stations and of corn breeders to determine what two varieties nick to best advantage in producing seed for different environments. Whether the yearly production of a particular first- generation cross will be found advisable, or whether its use in making other crosses will be found more profitable, must be estabhshed by further work, and perhaps for each individual case. Progress in producing higher yielding strains of corn depends upon the proper combination and application of the effects of acclimatization, adapta- tion, crossbreeding, and selection. 218 INDEX. Page. Acclimatization, factor in the production of higher yields of corn 7-9, 18-19, 27, 30, 36, 63, 66-67 See also Adaptation. Adaptation, factor in the production of higher yields of corn 8-10, 18-22, 28-30, 37, 62-63, 64, 66-67 See also Acclimatization. Age of seed. See Corn, age. Alabama, adapted varieties of corn 43-44 Averages. See Crossbreeding. Beal, W. J., on crossbreeding corn 64 California, adapted varieties of corn 20, 27 tests in crossbreeding corn 20, 24-30, 65, 66 Chico, Cal., tests in crossbreeding corn. See Experiments. Climate. See Acclimatization. Collins, G. N., on crossbreeding corn 64 Connecticut, adapted variety of corn 10, 20 Corn, age of seed, factor in the production of higher yields 15-16, 64, 66 crossbreeding tests. See Crossbreeding and Experiments. crosses, advantageous and disadvantageous 18-21, 62, 66-67 comparison with parent varieties 12-30, 33^1, 50-67 need of experimental tests to ascertain yield 8, 30, 42, 67 ranked according to grain production 23, 61, 63 facility of crossbreeding due to structure of floral parts 8,11 first-generation crosses, comparison with parent varieties 7, 9, 10, 12-28, 33^2, 50-67 matmity of seed, factor in production of higher yields 66 productiveness of crosses and parent varieties. See Yield. seed, comparative yield of years 1908 and 1909 15-16 crossbred and pure-bred, growing for comparison 8, 11 vitality tests. See Germination. self-fertilization a factor in reduction of yield 8, 64 See also Yield, factors influencing. varieties, Aldrich Perfection, crossing experiments 42, 45, 47-51, 61, 63 Bloody Butcher, crossing experiments 10 Blow, crossing experiments 31, 33-35, 40 Boone County Wliite, crossing experiments 10, 20, 31, 44 Chisholm, crossing experiments 31—12, 67 Clarage, crossing experiments 10 Cocke Prolific, crossing experiments 42, 45, 47, 48, 51, 52, 61, 63 Cross 100 10, 13, 15, 17-20, 23, 25, 26, 29 120, crossing experiments 10, 13, 15-21, 23, 25, 26, 28, 29 182, crossing experiments 19 Dan Patch, crossing experiments 31, 33, 35, 36, 39, 42 Dotson, crossing experiments 10, 20 Ferguson Yellow, crossing experiments 31, 33-37, 39, 40 First-Generation Cross 182, crossing experiments 19 218 69 70 CROSSBREEDING CORN. Page, Com, varieties, Fraley Yellow Dent, crossing experiments 10, 13, 15, 17, 18, 20, 21, 22, 25, 26, 29 Golden Eagle, crossing experiments. 10, 13, 15-18, 20, 23, 25, 26, 28, 29 Gorham Yellow, crossing experiments 31, 33-35, 39-41 Gourd Seed, crossing experiments 31, 33-35, 39, 41 Hickory King, crossing experiments 10, 13-20, 23, 25, 26, 29 Huffman, crossing experiments 31, 33, 35, 40 Illinois Learning, crossing experiments. ... 10, 13, 14, 16-19, 23, 25, 26 Laguna, crossing experiments 31 Lily of the Valley, crossing experiments 31, 33, 35, 36, 39 McCullough, crossing experiments 31, 33-35, 37, 39-41 Marlboro Prolific, crossing experiments 42, 44-48, 50-63 Mosby Prolific, crossing experiments 31, 33-35, 39, 40, 43, 45, 47, 48, 53, 54, 61, 63 Munson, crossing experiments 31, 33-35, 39, 40 Native of Statesboro, crossing experiments. 43, 45, 47, 48, 54, 55, 61, 63 Ohio Learning, crossing experiments 10, 13, 14, 17-19, 23, 25-29 Red Blaze, crossing experiments 10, 13, 15, 17, 18, 23, 25, 26, 28, 29 Reid Yellow Dent, crossing experiments. . . 10, 13, 14, 17, 18, 23, 25, 26 Rodgers ^Miite Dent, crossing experiments 43, 45-48, 51-63 Sanders Prolific, crossing experiments 43, 45, 47, 48, 56, 57, 61, 63 Schieberle, crossing experiments 31, 33-35, 39, 40 Selection 77, crossing experiments 10, 13, 15-18, 20, 22, 23, 25, 26, 28, 29 78, crossing experiments 10, 14, 15, 17, 18, 23, 25, 26 119, crossing experiments 10-29, 67 136, crossing experiments 31, 33-35, 39, 41 137, crossing experiments 10, 12, 14, 17, 25, 26, 29, 31, 33-36, 39-41 138, crossing experiments 10, 12, 14, 17, 25, 26, 28 159, crossing experiments 10, 12, 14, 17, 25, 26 160, crossing experiments 27-29, 67 Silvermine, crossing experiments 10, 13, 14, 16-18, 20, 23, 25-29 Singleton, crossing experiments 31, 33-35, 37, 39, 40 Station Yellow, crossing experiments 43, 45, 47, 48, 57, 58, 61, 63 Sturges Hybrid Flint, crossing experiments 10, 13, 14, 16-18, 20, 23, 25, 26, 29 Surcropper, crossing experiments 31, 33-36, 39-41 Tindal, crossing experiments 44, 45, 47, 48, 58, 59, 61-64 Whelchel, crossing experiments 44, 45, 47-50, 59 WTiitecap, crossing experiments 10, 13, 14, 17-19, 23-26, 29 Williamson, crossing experiments 44, 45, 47, 48, 60, 61, 63 See also related topics; as, Acclimatization, Adaptation, Experiments, Germi- nation, Intermediacy, Selection, Yield, etc. Corsicana, Tex., tests in crossbreeding corn. See Experiments. Crossbreeding, facility of use of floral parts with corn 8, 11 unreliability of averages for specific instances 65-67 See also Corn, crosses; Fertilization; Experiments; Inflorescence; Methods, etc. Delaware, adapted varieties of corn 10, 19 Derwood, Md., tests in crossbreeding corn. See Experiments. District of Columbia, source of varieties of corn 10, 19, 46 EarUness, factor in productiveness of corn 18, 23, 36, 66 East, E. M., and Hays, H. K., on crossbreeding corn 64 218 INDEX. 71 Page. Eaat, E. M. , on crossbreeding corn 64 Environment. See Adaptation. Experiineuts in crossbreeding corn at Chico, Cal 24-30 Corsicana, Tex 30, 32, 34-37, 39-42 Derwood, Md 10-14, 16, 20 Pike Crossing, Md 11, 12, 14-15 Sherman, Tex 30, 32-37, 39-42 Statesboro, Ga 42-64 Waco, Tex 30,32^2 See also Corn, crosses, need of experimental tests. Fertilization of corn, method of crossing varieties 11, 27 Fertilizer, application to land used in corn crossbreeding tests 46, 49 First-generation crosses. See Corn, first-generation crosses. Gardner, F. D. , and Morrow, G. E. , on crossbreeding corn 64 Georgia, adapted varieties of corn 31, 43, 44 tests in crossbreeding corn 42-64, 65 Germination, results of tests of seed corn 9-10, 16, 46-47, 66 Grain, comparison of yield of corn crosses and parent varieties 8, 12-30, 33-42, 50-62, 66, 67 Harvesting, methods used in corn crossbreeding tests 46, 49 Hays, H. K., and East, E. M., on crossbreeding corn 64 Illinois, source of varieties of corn 10 Inbreeding, factor in reducing yields of corn 8 See also Corn, self-fertilization. Indiana, source of variety of corn 10 Indian corn. See Maize. Inflorescence of corn, relation to crossbreeding 8, 11, 30 Ingersoll, C. L., on crossbreeding corn 64 Intermediacy, indications in crosses of corn 64-65 Introduction to bulletin 7-9 Isolation, factor influencing yield of corn 8, 11, 28 Kansas, source of variety of corn 31 Kellerman, W. A. , and Swingle, W. T. , on crossbreeding corn 64 McCluer, G. W. , on crossbreeding corn 64 Maize, factors influencing evolution 7,8 See also Corn. Maryland, adapted varieties of corn 10, 19-22 tests in crossbreeding corn 9-24, 30, 65, 66 Methods, application of principles in crossbreeding corn 7-9, 11-12, 16, 18-19, 21, 22, 24, 27-28, 30, 33-35, 37, 41-42, 46-49, 65, 66 Mexico, soiu-ce of variety of corn 31 Mississippi, source of variety of corn 31 Moisture in shelled corn, crosses and parent varieties compared. 17-19, 21, 32, 49-50, 65 soil, relation to yield of com 32, 36-37, 66 See also Rainfall. Morrow, G. E., and Gardner, F. D., on crossbreeding com 64 Nebraska, source of variety of corn 10 Nick, use of term as applied to crossbreeding corn 30, 66-67 North Carolina, source of varieties of corn 42 218 72 CROSSBREEDING CORN. Page. Ohio, adapted varieties of corn 10, 20 Pike Crossing, Md., tests in crossbreeding corn. See Experiments. Pollination. See Fertilization. Productiveness of corn. See Yield. Rainfall, relation to yield of corn 24, 49 Sanborn, J. W., on crossbreeding corn 64 Seasons, influence on the production of yields of corn 7, 36, 63-64 See also Rainfall. Seed corn. See Corn, seed. Selection, factor in the production of higher yields of com 7-9, 19, 20, 67 Self-fertilization. See Corn, self-fertilization. Sherman, Tex., tests in crossbreeding corn. See Experiments. Shull, G. H., on crossbreeding corn 64 Silks of corn. See Inflorescence. Soil, conditions iu various crossbreeding tests. 7, 11, 12, 18, 20, 21, 24, 32-34, 36, 37, 45, 47 South America, source of varieties of corn 31 South Carolina, source of varieties of com 42-44 Statesboro, Ga., tests in crossbreeding corn. See Experiments. Stover, comparison of yield of com crosses and parent varieties 12-15, 17, 23-24, 26, 50-62 Swingle, W. T., and Kellerman, W. A., on crossbreeding corn 64 Webber, H. J., on crossbreeding com 64 « Tassels of com. >See Inflorescence. Tennessee, source of varieties of corn 10, 31 Tests in crossbreeding corn, general consideration 64-67 See also Corn, Experiments, Yield, etc. Texas, adapted varieties of com 10, 31, 36 tests in crossbreeding com 30-42, 65, 66 Vanatter, P. O., on crossbreeding corn 64 Varieties of corn used in tests 10, 12-15, 17, 18, 23, 25, 26, 28, 31, 33-35, 39, 40, 42-45, 47, 48, 50-61, 63 See also Corn, varieties. Virginia, adapted varieties of corn 21-22 Vitality of seed com. See Gemiination. Waco, Tex., tests in crossbreeding corn. See Experiments. Washington, D. C, source of varieties of corn 10, 19, 46 Webber, H. J., and Swingle, W. T., on crossbreeding com 64 Weevils, damage to varieties of corn 42-44 Yield, comparison of crosses and parent varieties of corn 12-30, 32-42, 50-67 See also Grain and Stover, factors influencing productiveness of corn 7-9, 19, 22, 28-30, 62-64, 66 218 o U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF PLANT INDUSTRY— BULLETIN NO. 219. B. T. GALLOWAY, Chief of Bureau. AMERICAN MEDICINAL LEAVES AND HERBS. BY ALICE HENKEL, AssistoMt, Drug-Plant Investigations. Issued December 8, 1911. WASHINGTON: GOVERNMENT PRINTING OFFICB. 1911. U. S. DEPARTMENT OE AGRICULTURE. BUREAU OF PLANT INDUSTRY— BULLETIN NO. 219. B. T. GALLOWAY, CkicJ' of Bureau. AMERICAN MEDICINAL LEAVES AND HERBS. BY ALICE HENKEL, Assistant, Drug-Plant Investigations. Issued Dkcember 8, 1911. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1911. BUREAU OF PLANT INDUSTRY. Chief of Bureau, Beverly T. Galloway. Assistant Chief of Bureau, Willlvm A. Tayloe. Editor, J. E. Rockwell. Chief Clerk, James E. Jones. Drug-Plant, Poisonous-Plant, Physiological, and Fermentation Investigations. scientific staff. Rodney H. True, Physiologist in Charge. A. B. Clawson, Hcinrich Hasselbring, C. Dwight Marsh, and W. W. Stockberger, Physiologists. H. H. Bunzel, James Thompson, and Walter Van Fleet, Experts. Carl L. Alsberg, H. H. Bartlett, Otis F. Black, Frank Rabak, and A. F. Sievers, Chemical Biologists. W. W. Eggleston, Assistant Botanist. S. C. Hood, G. F. Mitchell, and T. B. Young, Scientific Assistants. Alice Henkel, A ssuitajit. . G. A. Russell, Special Agent. 219 2 I LETTIiR OF TRANSMITTAL. U. S. Department of Agriculttjre, Bureau of Plant Industry, Office of the Chief, Washington, D. C, April 15, 1911. Sir: I have the honor to transmit herewith and to recommend for pubhcation as Bulletin No. 219 of the series of this Bureau the accom- panying manuscript, entitled "American Medicinal Leaves and Herbs." This paper was prepared by Miss Alice Henkel, Assistant in Drug-Plant Investigations, and has been submitted by the Physiolo- gist in charge with a view to its publication. Thirty-six plants furnishing leaves and herbs for medicinal use are fully described, and in some instances brief descriptions of related species are included therewith. Of the above number, 15 are official in the United States Pharmacopoeia. This bulletin forms the third installment on the subject of American medicinal plants and has been prepared to meet the steady demand for information of this character. It is intended as a guide and refer- ence book for those who may be interested in the study or collection of the medicinal plants of this country. The first bulletin of this series treats of American root drugs, and the second of American medicinal barks. Respectfully, Wm. A. Taylor, Acting Chief of Bureau . Hon. James Wilson, Secretary of Agriculture. ■219 8 CONTENTS. Page. Introduction 7 Collection of leaves and herbs 7 Plants furnishing medicinal leaves and herbs 8 Sweet fern ( Comptonia percgrina) 9 Liverleaf (Ifcpatica hepatica and H. acuta) 10 Celandine ( Chelidoniutn viajus) 11 Witch-hazel (Hamamelis virginiana) 12 American senna ( Cassia marilandica) 13 Evening primrose (Oenothera biennis) 14 Yerba santa (Eriodictyon caUfornicum) 15 Pipsissewa ( Chimaphila umbcllata) •. 16 Mountain laurel (Kalmia latifolia) 17 Gravel plant (Epigaea repens) 18 Wintergreen (Gaultheria procumbens) 19 Bearberry (Arctostaphylos ii va-ursi) 20 Buckbean ( Menyanthes trifoliata) 21 Skullcap (Scutellaria lateriflora) 22 Horehound ( Marrubium vulgare) 23 Catnip ( Ncpeta cataria) 24 Motherwort (Leonunis cardiaca) 25 Pennyroyal (Hedeoma pulegioides) 26 Bugleweed (Lycopns virginicus) 27 Peppermint ( Mentha piperita) 28 Spearmint ( Mentha spicata) 29 Jimson weed (Datura stramonium) 30 Balmony (Chelone glabra) 31 Common speedwell ( Veronica officinalis) 32 Foxglove (Digitalis purpurea) 32 Squaw vine ( Mitchella repens) 34 Lobelia (Lobelia inflata) 35 Boneset (Eupatorium perfoliatum) 36 Gum plant (Grindelia robusta and G. squarrosa) 37 Canada flea bane (Leptilon canadense) 38 Yarrow (Achillea millefolium) 39 Tansy ( Tanacetum vulgare) 40 Wormwood (Artemisia absinthium ) 41 Coltsfoot ( Tussilago farfara) 42 Fireweed (Erechthites hieracifolia) 43 Blessed thistle ( Cnicus benedictus) 44 Index ,, 45 219 5 ILLUSTRATIONS Page. Fig. 1. Sweet fern (Comptonia peregrina), leaves, male and female catkins 9 2. Liverleaf (Hepatica hepatica), flowerins; plant 10 3. Celandine {Chelidonium mnjus), leaves, flowers, and seed pods 11 4. Witch-hazel (Hamamelis virginiana), leaves, flowers, and capsules 12 5. American senna (Cassia marilandica), leaves, flowers, and seed pods. . 13 6. Evening primrose (Oenothera biennis), leaves, flowers, and capsules... 14 7. Yerba santa (Eriodictyon calif ornicum) , leaves and flowers 15 8. Pipsissewa and spotted wintergreen (Chimaphila iimbellata and C. macu- lata), flowering and fruiting plants 16 9. Mountain laurel (Kalmia latifolia), leaves and flowers 17 10. Gravel plant (Epigaea repens), leaves and flowers 18 11. Wintergreen (Gaultheria procumbens) , flowering and fruiting plants. . . 19 12. Bearberry (Arctostaphylos uva-ursi), leaves and fruitsl 20 13. Buckbean (Menyanthes trifoliata), flowering plant 21 14. Skullcap (Scutellaria lateriflora), flowering branch, showing also seed capsules 22 15. Horehound (Marrubium vulgare), leaves, flowers, and seed clusters. . . 23 16. Catnip (Nepeta cataria), leaves and flowers 24 17. Motherwort (Leonurus cardiaca), leaves, flowers, and seed clusters 25 18. Pennyroyal (Hedeoma pulegioides) , leaves and flowers'. 26 19. Bugleweed (Lycopus virginicus), leaves and flowers 27 20. Peppermint (Mentha piperita), leaves and flowers 28 21. Spearmint (Mentha spicata), leaves, flowers, and running rootstock 29 22. Jimson weed (Datura stramonium), leaves, flowers, and capsules 30 23. Balmony (Chelone glabra), leaves and flowers 31 24. Common speedwell ( Veronica officinalis), leaves and flowers 32 25. Foxglove (Digitalis purpurea), leaves and flowers 33 26. Squaw vine ( Mitchella repens), leaves and fruits 34 27. Lobelia (Lobelia injlata), leaves, flowers, and inflated capsules 35 28. Boneset (Eupatorium per/oliatum) , leaves and flowers 36 29. Scaly grindelia (Grindelia squarrosa), leaves and flowers 37 30. Canada fleabane (Leptilon canadense), flowering tops 38 31. Yarrow (Achillea millefolium), leaves and flowers 39 32. Tansy ( Tanucctum vulgare), leaves and flowers 40 33. Wormwood (Artemisia absinthium), leaves and flowers 41 34. Coltsfoot (Tussilago farfnra) , plant showing root, leaves, and flowers... 42 35. Fireweed (ErecKthites hieracifolia), leaves and flowering tops 43 36. Blessed thistle ( Cnicus benedictus), leaves and flowers 44 219 6 B. p. I.— 669. AMERICAN MEDICINAL LEAVES AND HERBS. INTRODUCTION. Less difficulty will be encountered in the collection of leaves and herbs than in the case of other portions of plants, for not only is recognition easier, since, especially in the matter of herbs, these parts are usually gathered at a time when the plants are in flower, but the labor is less arduous, for there are no roots to dig or barks to peel. Of the three dozen medicmal plants mentioned in this bulletin, 15 are recognized as official in the Eighth Decennial Revision of the United States Pharmacopoeia. This is more than half of all the leaves and herbs included in the Pharmacopoeia. Among the plants included in this bulletin are peppermint and spearmint, which are found not only in the wild state but the culti- vation of which for the distillation of the oil constitutes an impor- tant American industry. Especially is this true of peppermint? thousands of acres being devoted to the cultivation of this plant, prmcipally in the States of Michigan and New York. A number of other plants mentioned in this paper furnish usefid oils, such as oil of wintergreen, pennyroyal, fleabane, tansy, wormwood, and fire- weed. As in the case of other bulletms of this series, an effort has been made to include in it only such plants as seem most in demand, lack of space forbidding a consideration of others which are or have been used to a more limited extent. With two or three exceptions the illustrations have been reproduced from photographs taken from nature by Mr. C. L. Lochman. COLLECTION OF LEAVES AND HERBS. Leaves are usually collected when they have attained full develop- ment and may be obtained by cutting off the entire plant and strip- ping the leaves from the stem, using a scythe to mow the plants where they occur in sufficient abundance to warrant this, or the leaves may be picked from the plants as they grow in the field. Wlienever the plants are cut down in quantity they must be care- fully looked over afterwards for the purpose of sorting out such 5l9 7 8 AMERICAN MEDICINAL LEAVES AND HEEBS. other plants as may have been accidentally cut with them. Stems should be discarded as much as possible, and where a leaf is composed of several leaflets these are usually detached from the stems. In gathermg herbs only the flowering tops and leaves and the more tender stems should be taken, the coarse and large stems bemg rejected. All withered, diseased, or discolored portions should be removed from both leaves and herbs. In order that they may retain their bright-green color and char- acteristic odor after drying, leaves and herbs must be carefully dried in the shade, allowing the air to circulate freely but keeping out all moisture; dampness will darken them, and they must therefore be placed under cover at night or in rainy weather. A bright color is desirable, as such a product wiU sefl more readily. To dry them the leaves and herbs should be spread out thinly on clean racks or shelves and turned frequently until thoroughly dry. They readily absorb moisture and when perfectly cured should be stored in a dry place. Leaves and herbs generally become very brittle when they are dry and must be very .carefully packed to cause as little crushing as pos- sible. They should be firmly packed in sound burlap or gunny sacks or in dry, clean boxes or barrels. Before shipping the goods, how^ever, good-sized representative samples of the leaves and herbs to be dis- posed of should be sent to drug dealers for their inspection, together with a letter stating how large a quantity the coUector has to sell. With the changes in prices that are constantly taking place in the drug market it is, of course, impossible to give definite prices 'in this paper, and only approximate quotations are therefore included in order that the collector may form some idea concerning the possible range of prices. Only through correspondence with drug dealers can the actual price then prevailing be ascertained. PLANTS FURNISHING MEDICINAL LEAVES AND HERBS. Each section contains synonyms, the pharmacopoeial name (if any), the common names, habitat, range, descriptions, and information concerning the collection, prices, and uses of the plants. The medicinal uses are referred to in a general way only, since it is not within the province of a publication of this kind to give detailed information in regard to such mattei-s. Advice concerning tlie proper remedies to use should be sought only from physicians. The state- ments made in this paper as to medicinal uses are based on informa- tion contained in various dispensatories and other works relating to materia medica. 219 PLANTS FURNISHING MEDICINAL LEAVES AND HERBS, 9 SWEET FERN. Comptonia peregrina (L.) Coullor. Synonyms.— rComptonia as plenifolia Gaertn.; Myrira itsplenifoUa L.; Liquidambor asplenifolia L.; Liquidamhar peregrina L. Other common names. — Kern gale, fern bush, meadow fern, shrubby fern, Canada tivveet gale, spleenwort bush, sweet bush, sweet ferry. Habitat and range. — Sweet fern is usually found on hillsides, in dry soil, in Canada and the northeastern United States. It is indigenous. Description. — The fragrant odor and the resemblance of the leaves of this plant to those of a fern have given rise to the common name "sweet fern." It is a shrub with reddish-brown bark, growing from about 1 to 3 feet in height, with slender, erect or spread- ing branches, the leaves hairy when young. The thin narrow leaves are borne on short stalks and are linear oblong or linear lance shaped, about 3 to (5 inches long and from one-fourth to half an inch wide, deeply divided into many lobes, the margins of which are generally en- tire or sparingly toothed. The catkins expand with the leaves. (Fig. 1.) The staminate or male ilowers are produced in cylindrical catkins in clusters at the ends of the branches and are about an inch in length, the kidney-shaped scales overlapping. The pistil- late or female flowers are borne in egg-shaped or roundish-oval catkins, the eight awl-shaped bractlets persisting and surround- ing the one-seeded, shining, light-brown nut, giving it a burlike appearance. The whole plant has a spicy, aromatic odor, which is more pronounced when the leaves are bruised. Sweet fern belongs to the bayberry family (Myricacea^). Collection, prices, and uses. — The entire plant is used, but especially the leavc,-^ and tops. It has a fragrant, spicy odor and an aromatic, slightly bitter, and astringent taste. The present price of sweet fern is about 3 to 5 cents a pound. It is used for its tonic and astringent properties, jirincipallj in a domestic way, as a remedy in diarrheal complaints. 97225°— Bui. 219—11 2 Fig. 1. -Sweet fern (Comptonia peregrina), leaves, male and female catkins. 10 AMERICAN MEDICINAL LEAVES AND HERBS. LIVERLEAF. (1) Jfepatica hepatica (!>.) Karst.; (2) TTepatica acuta (Pursh) Britton. Synonyms. — (1) Hepatica triloba Chaix.; Anemone hepatica h. (2) Hepatica triloba var. acuta Pursli: Ilepatica acuiiloba DC. Other common names. — (1) Round-leaved hepatica, common liverleaf, kidney liver- leaf, liverwort (incorrect"), noble liverwort, heart liverwort, three-leaved liverwort, liverweed, herb-trinity, golden trefoil, ivy flower, mouse-ears, squirrel cup; (2) heart liverleaf, acute-lobed liverleaf, sharp-lobed liverleaf, sharp-lobed hepatica. Habitat and range. — The common liverleaf is found in woods from Nova Scotia to northern Florida and west to Iowa and Missouri, while the heart liverleaf occurs from Quebec to Ontario, south to Georgia (but rare near the coast), and west to Iowa and Minnesota. Description. — The hepat- icas are among the earliest of oTir spring flowers, blos- soming about March, and frequently before that time. They grow only about 4 to 6 inches in height, with leaves pro- duced from the roots on long soft-hairy stalks and spreading on the ground. The thick and leathery evergreen leaves are kid- ney shaped or roundish and deeply divided into three oval, l)lunt lobes; the young leaves are pale green and soft hairy, but the older ones become leathery and smooth, expanding when mature to almost 3 inches across; they are dark green above, sometimes with a purplish tinge, and also of a purplish color on the under surface. The flowers, which are about one-half inch in diameter, are borne singly on slender, hairy stalks arising from the root, and vary in color from bluish to purple or white. Immediately beneath the flower are three small, stemless, oval, and blunt leaflets or bracts, which are thickly covered with soft, silky hairs. (Fig. 2.) The heart liverleaf is very similar to the common liverleaf. It grows perhaps a trifle taller and the lobes of the leaf and the small leaflets or bracts immediately under the flower are more sharply pointed. The hepaticas are members of the crowfoot family (Ranunculacese) and are perennials. The name "liverwort," often given to these plants, is incorrect, since it belongs to an entirely different genus. Collection, prices, and uses. — The leaves, which were official in the United States Pharmacopoeia from 1830 to 1880, are the parts employed; they should be collected 219 Fig. 2. — Liverleaf (^fpgtico hepatica), flowering plant. PLANTS FURNISHING MEDICINAL I.KAVES AND IIKKBS. 11 in April. They lowt; about three-fourths of their \vei<^ht in dryiuf^. The price at j)renent paid for them is al)out 4 to 5 cents a pound. Liverleaf is employed for its tonic properties and is said lo he useful in affections of the liver. CELANDINE, Chelidonium run jus l>. Other common names. — Chelidonium, garden celandine, greater celandine, tetter- wort, kilhvart, wart flower, wartweed, wartwort, felonwort, cockfoot. devil's-milk, Jacob's ladder, swallow- wort, wretweed. Habitat and range. — Cel- andine, naturalized from Europe, is found in rich damp soil along fences and roadsides near towns from Maine toOntarioandsouth- ward It is common from southern Maine to Penn- sylvania. Description. — This plant, which has rather weak, brittle stems arising from a reddish-brown, branch- ing root, is a biennial be- longing to the poppy fam- ily (Papaveraceae) and, like other members of this family, contains an acrid juice, which in this species is colored yellow. It is an erect, branched, spar- ingly hairy herb, from about 1 to 2 feet in height with thin leaves 4 to 8 inches in length. The leaves, which are lyre shaped in outline, are deeply and variously cleft, the lobes thus formed be- FlG. -Celandine (Chelidonium majus), leaves, flowers, and seed pods. ing oval, blunt, and wavy or round toothed, or rather deeply cut. They have a grayish-green appearance, especially on the lower surface. The small, 4-petaled, sulphur-yellow flowers of the celandine are produced from about April to Septem- ber, followed by smooth, long, pod-shaped capsules crowned with the persistent style and stigma and containing numerous seeds. (Fig. 3.) Collection, prices, and uses. — The entire plant, which was official in the United States Pharmacopoeia for 1890, is used. It should be collected when the herb is in flower. At present it brings about 6 or 8 cents a pound. The fresh plant has an impleasiant, acrid odor when bruised, but in the dried state it is odorless. It has a persistent acrid and somewhat salty taste. Celandine is an old remedy. It has cathartic and diuretic properties, promotes perspiration, and has been used as an expectorant. The juice has been employed externally for warts, corns, and some forms of skin diseases. 219 12 AMEEICAN MEDICINAL LEAVES AND HEKBS. WITCH-HAZEL. Hamamelis virginiana L. Phannacnpoeml name. — Hamamolidis folia. Other common names. — Snapping hazel, winterbloom, wych-hazel, striped alder, spotted alder, tobacco wood. Habitat and range. — The home of this native shrub is in low damp woods from New Bruns\\'ick to Minnesota and south to Florida and Texas. Description. — This shrub, while it may grow to 25 feet in height, is more frequently found reaching a height of only 8 to 15 feet, its crooked stem and long forking branches covered with smoothish brown bark sometimes with an addition of lichens. A peculiar feature about %\-itch-hazel is its flowering in very late fall or even early winter, when its branches are destitute of leaves, the seed forming but not ripen- ing until the following season. The leaves are rather large, 3 to 5 inches long, thick, and borne on short stalks; they are broadly oval or heart- shaped oval, sometimes pointed and sometimes blunt at the apex, with un- even sides at the base, and wavy margins. The older leaves are smooth, but when young they are covered with downy hairs. The upper surface of the leaves is a light- green or bro\vnish-green color, while the lower surface is pale green and somewhat shining, with prominent veins. The threadlike bright-yellow flowers, which appear very late in autumn, are rather odd looking and consist of a 4-parted corolla with four long, narrow, strap- shaped petals, which are twisted in vari- ous ways when in full flower. The seed capsule does not mature until the follo\\-ing sea- eon, when the beaked and densely hairy seed case bursts open elasticall y , scattering with great force and to a considerable distance the large, shining-black, hard seeds. (Fig. 4.) This interesting shrub is a member of the witch-hazel family (Hamamelidacete). Collection, prices, and t/sfs.— Witch-hazel leaves are official in the United States Pharmacopoeia. They should be collected in autumn and c'arefully dried. Formeriy the leaves alone were recognized in the United States Pharmacopoeia, but now the bark and twigs are also official. The leaves have a faint odor and an astringent, some- what l)itt('r, and aromatic taste. They bring about 2 to 3 cents a pound. The soothing projjerlies of witch-liazel were known among the Indians, and it is still employed for the relief of inflammatory conditions. 219 Fig. 4.- -Witch-hazel( //a ;nom(7/4i;r(/jnmn«), leaves, flowers, and capsules. PLANTS FURNISHING MEDICINAL LEAVES AND HERIJS. 13 AMERICAN SENNA. Cassia marilandica Ij. Synonym. — Senna vfiarilandica Link. Other common names. — Wild soiina, locust plant. Habitat and range. — American senna generally frequents wet or swampy soils from New England to North Carolina and westward to Louisiana and Nebraska. Description. — This is a native species, a member of the senna family (Caesalpini- acese), which is closely related to the pea family. It is a perennial herb, its round grooved stems reaching about 4 to 6 feet in hei,^Cr k ^m:^^ W$!^ ^^ ^^L^i 'W/'.^ > k^iif iii^i v^ ^mk^T' m^w ^M^ \ FiCr. 7.— Yerba santa (Eriodictyon califomicum), loaves and flowers. ' A popular but misleadine; name. 219 16 AMERICAN MEDICINAL LEAVES AND HERBS. PIPSISSEWA. Chimnphila umbellata (L.) Niitt. Pharmacopoeial name. — Chimaphila . Synonyms. — PyroJa umbellata L.; Chimaphila corymbosa Pursh. ()th<'r common nanies. — Prince's pine, pyrola, rheumatism weed, hitler wiutergreen, groiind holly, king's cure, love-in-winter, noble pine, pine tulip. Habitat and range. — Pipsissewa is a native of this country, growing in dry, shady woods, especially in pine forests, and its range ex- tends from Nova Scotia to British Columbia, south to Georgia, Mexico, and Cali- fornia. It also occurs in Europe and Asia. Description. — This small perennial herb, a foot or less in height, has a long, run- ning, partly underground stem. It belongs to the heath family (Ericaceis) and has shining evergreen leaves of a somewhat leath- ery texture placed in a cir- cle around the stem, usually near the top or scattered along it. They are dark green, broader at the top, with a sharp or blunt apex, narrowing toward the base and with margins sharply toothed; they are from about 1 to 2 inches long and about three-eighths to a lit tie more than half an inch wide at the broadest part. From about June to August the pipsissewa may be found in flower, its pretty waxy-white or ))inkish fra- FiG. 8.— i'ii)sisse\va (B) and spotted wiiiteri^reeii {A) (Chimaphila umbellata and C. maculala), flowrrins and fruiting plants. grant flowers, consisting of five rounded, concave petals, each one with a dark-pink spot at the base, nodding in clusters from the top of the erect stem. The brown capsules contain numerous very small seeds. (Fig. 8.) Collection, prices, and uses. — Although the United States Pharmacopoeia directs that the leaves be used, the entire i)lant is frecjuently employed, as all parts of it are active. Pipsissewa leaves have no odor, but a bitter, astringent taste. They bring about 4 cents a ])ound. Pipsissewa has slightly tonic, astringent, and diuretic prop- erties and is sometimes employed in rheumatic and kidney affections. Externally it has been applied to ulcers. ,'.'.• Another species. — The leaves of the spotted wintergreen (C/imap/aVa maculata Pursh) were ofTicial in the Pharmacopa'ia of the United States from 1830 to 1840. These may be distingui.shod from the leaves of ('. umbellata (pii)sissewa) by their olive-green color marked with white along the midrib and veins. They are lance shaped in out- line and are broadest at the base instead of at the top as in C. umbellata. PLAJMTS i''L'KjSIlSllIi\C! MKDK J NAI. I.KAVKS AND IlKKDS. 17 MOUNTAIX LAUREL. Kalmia latifoUa L. Otlicr common navies. — Broad-leaved laurel, broad-leaved kalmia, American huiiol, sheep laurel, rose laurel, spurge laurel, suiall laurel, wood laurel, kalmia, calico bush, sjjoouwood, s])oou- hiuit, ivy bush, big-leaved ivy, wdcky, calmoun. Habitat and range. — The mountain laurel is found in sandy or rocky soil in woods from New Bruns- wick south to Ohio, Flor- ida, and Louisiana. Description. — This is an evergreen shrub fromabout 4 to 20 feet in height, with leathery leaA-es, and when in flower it is one of the most beautiful and showy of our native plants. It has very stiff branches and leathery oval or elliptical leaves borne on stems, mostly alternate, pointed at both ends, with margins entire, smooth and bright green on both sides, and having terminal, clammy- hairy clusters of flowers, which appear from about May to June. The buds are rather oddly shaped and fluted, at first of a deep rose color, expanding ^lo- 9.— Mountain laurel {Kalmia lafifolia).\e^\es and flowers, into saucer-shaped,. more delicately tinted, whitish-pink flowers. Each saucer-shaped flower is provided with 10 pockets holding the anthers of the stamens, but from which these free themselves elastically when the flower is fully exj^anded. (Fig. 9.) The seed capsule is somewhat globular, the calyx and threadlike style remaining attached until the capsules open. Mountain laurel, which belongs to the heath family ( Ei'icaceaO, is poisonous to sheep and calves. Collection, prices, and uses. — The leaves, which bring about 3 to 4 cents a pound, are collected in the fall. They are used for their astringent properties, 97225°— Bui. 219—11 3 18 AMERICAN MEDICI^'AL LEAVES AND HERBS. GRAVEL PLANT. Epigaea repens L. Other common names. — Trailins^ urbulus. Mayflower, shad-flower, ground laurel, mountain pink, winter pink. Habitat and range. — This shrubby little plant, spreads out on the ground in sandy soil, being found especially under evergreen trees from Florida to Michigan and northward. Description. — The gravel plant is one of our early spring flowers, and under its more popular name "trailing arbutus" it is greatly prized on account of its delicate shell-pink, waxy blossoms with their faint yet spicy fragrance. Gra^■el plant is the name that is generally applied to it in the drug trade. It spreads on the ground with. stems 6 inches or more in length and has rust-colored hairy twigs bearing ever- green leaves. The leaves are green above and below, thick and leathery, oval or roundish, sometimes with the top pointed, blunt, or having a short stiff point and a rounded or heart- shaped base. The mar- sins are unbroken and the Fig. 10.— Gravel plant (Epigaea repens), leave.s and flowers. upper surface is smooth, while the lower surface is somewhat hairy. The leaves measure from 1 to 3 inches in length and are about half as wide, the hairy stalks sup- porting them ranging from one-fourth of an inch to 2 inches in length. Early in the year, from about March to May, the flower clusters appear. These are borne in the axils of the leaves and at the ends of the branches and consist of several waxy, pinkish-white, fragrant flowers with saucer-shaped, 5-lobed corolla, the throat of the corolla tube being very densely hairy within. (Fig. 10.) The seed capsule is some- what roundish, flattened, five celled, and conti\ins numerous seeds. The gravel plant belongs to the heath family (Ericaceae) and is a perennial. Collection, prices, and uses. — The leaves are collected at flowering time and are worth about 3 or 4 cents a pound. Tliey have a bitter, astringont taste and are said to possess astringent and diuretic properties. 219 PLANTS FURNISHING MEDICINAL LEAVES AM) IIEKBS. 19 WINTERGREEN. Gaultheria procumbens L Other common names. — (laiiltheria, spring wintergreen, creeping wintergrecn, aromatic Avintergreen, spicy wintergreen, checkerberry, teaberry, partridge berry, grouseberry, t1 BUCK liEAN. Menyanthes Irifoliata I>. Other common names.- — ^Bog bean, bog luyrtJe, l)()g hop, bog nut,, brook 1)ean, l)ean trefoil, nuirsli trefoil, water trefoil, bitter trefoil, waler shann-ock, marsh clover, moonfiower, bitterworin. Ilahitut and range. — The l)iick bean is a marsh herb occurring in North America as far south as Pennsylvania, Minnesota, and California. It is also native in Europe. Description. — This per- ennial herb arises from a long, black, creeping, scaly rootstock, the leaves be- ing produced from the end of the same on erect sheathing stems measuring about 2 to 10 inches in height. The leaves con- sist of three oblong-oval or broadly oval leaflets H to 3 inches long, somewhat fleshy and smooth, blunt at the top. with margins entire and narrowed to- ward the base; the upper surface is pale green and the lower surface some- what glossy, with the thick midrib light in color. The flower cluster is produced from May to July on a long, thick, naked stalk arising from the rootstock It bears from 10 to 20 flowers, each with a funnel-shaped tul)e terminating in five segments which are pink- ish purple or whitish on the outside and whitish and thickly bearded with white hairs within. (Fig. 13.) The capsules which follow are ovate, blunt at the top, smooth and light brown, and contain numerous smooth and shining seeds. Buck bean is a perennial lielonging to the buck-bean family (Menyanthacese). Collection, prices, and uses. — The leaves are generally collected in spring. They lose more than three-fourths of their weight in drying. The price paid per pound is about 6 to 8 cents. Buck-bean leaves have a very bitter taste, but no odor. Large doses are said to have cathartic and sometimes emetic action, but the })rincipal use of buck-bean leaves is as a bitter tonic. They have been employed in dyspepsia, fevers, rheumatic and skin affections, and also as a remedy against worms. The rootstock is also sometimes employed medicinally and was recognized in tlie United States Pharmacopoeia from 1830 to 1840. 219 Fig. 13.— Buck bean {Menyanthes trifoHata), flowering jilanl. 22 AMERICAN MEDICINAL LEAVES AND HERBS. SKULLCAP. Scutellaria later ijlorn L. Pharmacopoeial name. — Scutellaria. Other common naviea. — American skullcap, blue skullcap, mad-dog skullcap, side- flowering skullcap, madwoed, hoodwort, blue pimpernel, hooded willow-herb. Ilahitat and range. — This species is native in damj) ])laces along banks of streams from Canada southward to Florida, New Mexico, and Washington. Description. — The lip- shaped flowers and squar- ish stems of the skullcap indicate that it is a member of the mint family (Men- thacese). It is a perennial of slender, erect habit, its square, leafy, branching stem ranging from 8 inches to 2 feet in height, smooth, or sometimes hairy at the top . The leaves are placed opposite to each other on the stem on slender stalks and are about 1 to 3 inches in length and about one- third as wide, thin in tex- ture, oblong or lance shaped, with margins coarsely toothed. They gradually become smaller toward the top, and sometimes those at the very top have the margins unbroken. The flowers are borne in narrow, spikelike, one-sided clus- ters, generally in the axils of the leaves, but frequent- ly also at the top, and are Fig. 14.— SkuUoap (Scutellaria laloi/lora}, floworin;; also seed capsules. branch, showing interspersed with leafy bracts. They appear from about July to September and are blue, shading off to whitish. Tlie tubular, 2-lipped flowers are about a quarter of an inch in length, and the calyx, or outer green covering of the flower, is also two lipped, the upper lip shaped like a helmet and closing in fruit. (Fig. 14.) Collection, prices, and uses. — The dried plant is at present official in the United States Pharmaropnria. The entire plant is collected when in flower and should be carefully dried in the shade. The price ranges from about 3 to 1 cents a jwund. Very frequently collectors will gather some other species in place of the official plant, most of those thus wrongly finding their way into the market being generally of stouter growth, with broader leaves and much larger flowers. This plant was once considered valuable for the prevention of hydrophobia, whence the names "mad-dog skullcap " and "madweed," but it is now known to be useless for that j)urpose. It is used principally as a tonic and to a limited extent for allaying nervous irritation of various kinds. 21lt PLANTS FURNISHING MEDICINA]. J. EAVES AND HERBS. 23 HOREiinrxi). Marruhium rulgarc L. Pharviacopceial name. — Marrubium. Other common muxes. — lloundsbene, nuirvcl, marrube. Habitat and range. — Ilorehound grows in dry sandy or stony soil in waste j^laces, along road.sides and near dwellings, in fields, and pastures. It is found from Maine to South Carolina, Texas, and westward to California and Oregon. It is very abundant in jiastures in Oregon and California, and especially in southern California, where it is a very trouble- some weed, covering vast areas and in such dense masses as to crowd out all other vegetation. It has been naturalized from Europe. Description. — The entire plant is thickly covered with hairs, which give it a whitish, woolly appearance. It is a bushy, branching herb, having a pleasant aromatic odor, and is about 1 to 3 feet high, with many woolly stems rounded below and four augled above, with opjiooite, oval or round- ish, wrinkled, strongly veined, and very hoary leaves. The leaves are about 1 to 2 inches in length, placed opposite each other on the stem, oval or nearly round, somewhat blunt at the apex, and narrowed or somewhat heart shaped at the base, the margins round toothed; the upper surface is wrinkled and somewhat hairy, while the lower surface is very hoary and prominently veined. The lip- shaped flowers, which appear from June to September, show that it is a member of the mint family (Mentha- ceae). These are borne in dense woolly clusters in the axils of the leaves and are whitish, two lipped, the upper lip two lobed, the lower three lobed. The hooked calyx teeth of the mature flower heads cling to the avooI of sheep, resulting in the scattering of the seeds. (I'^ig. 15.) Collection, prices, and nses.— The leaves and tops are the parts used in medicine and are official in the United States Pharmacopoeia. These are gathered just before the plant is in flower, the coarse stalks being rejected. They should be carefully dried in the shade. The odor is pleasant, rather aromatic, but diminishes in drying. The taste is bitter and persistent. Horehound at present brings about 1 \ to 2 cents a pound. It is well known as a domestic remedy for colds and is also used in dyspepsia and for expelling worms. 219 Fig. 15.— Horehound (Marrubium vulgare), leaves, flowers, and seed clusters. 24 AMEKlLA^S; MF-DTCTXAL LEAVES AND HERBS. CATNIP. Nepeta ratarin L. Other common names. — Cataria, catmint, calwort, calrup, field mint. ffabitat and range. — Catnip, a coinmnn weed naturalized from Europe, occurs in rather dry soil in waste places and cultivated land from Canada to Minnesota and south to Virginia and Arkansas. Description. — The fine white hairs on the stems of this plant give it a somewhat whitish appear- ance. Catnip reaches about 2 to 3 feet in height, with erect, square, and branched stems. It is a perennial belonging to the mint famih- (Menthacese). The opposite leaves are heart shaped or oblong, with a pointed apex, the upper surface green, the lower grayish green with fine white hairs, the mar- gins finely scalloped and I to 2J inches in length. About June to Septem- ber the many-flowered, rather thick spikes are produced at the ends of the stem and branches. The whitish flowers, dot- ted with purple, are two lipped, the upper lip notched or two cleft, the lower one with three lobes, the middle lobe broadest and sometimes two cleft. (Fig. 16). Collection, prices, and uses. — The leaves and flowering tops, which have a strong odor and a bitter taste, are collected when the plant is in flower and are carefully dried. The coarser stems and branches should be rejected. Catnip was official in the United States Pharmacopa^ia from 1840 to 1880. The price ranges from 3 to 5 cents a pound. Catnip is used as a mild stimulant and tonic and as an emmenagogue. quieting effect on the nervous system. IT.) Vu. ]i -CiUiiii) i.XcpcIa calnria), Icavps and flowor.- It also has a PLANTS FURNlSlllXCi .M KIMCl N A 1 l,KA\'i;S AM) IIKIIIiS. 25 MOTllKKAVOHT. Synonym. — Cardiaca riih/dris Moench. Other contnion names. — Throwwort, cowthworl, lion's-fail, lion's-ear. JIdbitat and range. — Motlierwort, naturalized from Eur()j)e and a native also of Asia, Ls found about dwellings and in v.aste i)laces, its range in this country ex- tending from Nova Scotia to North Carolina, Minne- sota, and Nebraska. Description. — The rather stout, erect, 4- angled stem of this peren- nial herb attains a height of from 2 to 5 feet, is spar- ingly hairy, and has up- right branches. The rough, dark-green leaves are borne on long stems, the lower ones rounded, about 2 to 4 inches wide and three to five lobed, the lobes pointed, toothed, or variously cut, the upper narrower ones three cleft with lance-shaped lobes. Motherwort flowers in summer, the pale-purple or pinkish lip-shai:)ed blossoms produced in the axils of the leaves being arranged in dense circles around the stem ; the up- per lip is densely covered with white, woolly hairs on the outside and the lower lip is three lobed and mottled. (Fig. 17.) Motherwort belongs to the mint family (Menthaceae). Collection, prices, and uses. — The leaves and flowering tops are collected during the flowering season. They have an aromatic odor and a very bitter taste. At present they bring about 3 to 5 cents a pound. Motherwort has stimulant, slightly tonic properties and is used also to jjromote perspiration. 97225°— Bui. 219—11 4 Fig. 17.- -Motherwort (Leonurzis cardiaca), leaves, flowers, and seed clusters. 2G AMERICAN MEDICTXAl. LEAVES AND HERBS. PEXXYROYAL. Iledcnma pulegioides (L.) Pers. T'harmacopoeial name. — Heck'oma. Other common names. — American pennyroyal, mock pennyroyal, squaw mint, tick- weed, stinking balm, mos- quito plant. Habitat and range. — Pen- nyroyal is found in dry soil from Nova Scotia and Quebec to Dakota and southward. Description. — This very strongly aromatic annual of the mint family (Men- ihacese) is of rather insig- nificant appearance, being a low-growing plant, about 6 inches to a foot or so in height, with a slender, erect, much-branched and somewhat hairy stem. •The opposite leaves are small, scarcely exceeding three-fourths of an inch in length and becoming smaller toward the top of the plant. They are borne on short stems and are ob- long ovate in shape, thin, blunt at the apex, nar- rowed at the base, and with margins sparingly toothed. The branchlets are four an- gled and somewhat hairy, and the loose flower clus- W' / ters, appearing from July to J-' 1 September in the axils of the leaves, consist of a few pale-bluish flowers with 2- uppcr tine enlirc or slightly notched or two lubed, while the I'Ki. Is.— Tennyroyal (Iltdeoma pukgiuidm), leaves and llower.s. lipped cijroUa, the ere PT.ANIS FrRNTSHIN(i M Kl il( I NA I . l.lvWKS ANH IIKHMS. 31 BALMONY. Chclntir gliihrti I,. Other cowmov vnvi('s.-T\ui]vh('a(\, (urtlc hlodiii, fislimontli, codhead, palt-rheum weed, snake-head, bitter herb, shell flower. Hahilal and range. — This native perennial grows in swamps and along streama from Newfoundland to Mani- toba and south to Florida and Kansas. Description. — Bahnony is a slender, erect herb, with a 4-angled stem 1 to 3 feet in height, occasion- ally branched. The short- stemmed leaves, which are from 3 to 6 inches in length, are narrowly lance shaped to broadly lance shaped, the lower ones sometimes broadly oval, naiTOwing toward the base and with margins fm*- nished with sharp, close- lying teeth. In late sum- mer or early fall the showy clusters of whitish or pink- ish flowers are produced. Each flower is about an inch in length, with a tubular, inflated corolla, with the mouth slightly open and resembling the head of a turtle or snake; its broad arched upper lip is keeled in the center and notched at the apex, while the lower lip is three lobed, the smallest lobe in the center, and the throat bearded with woolly hairs. (Fig. 23.) The seed capsule is oval, about half an inch in length, and contains numerous small seeds. Collection, prices, and uses.— The herb (especially the leaves), which brings from 3 to 4 cents a pound, should be collected during the flowering period. Balmony has a very bitter taste, but no odor, and is used as a tonic, for its cathnrtic properties, and for expelling worms. 219 Fig. 2.3.— Balmony (Ckclone i/Iabra). leaves and flowers. 32 AMERICAN MEDICINAL LEAVES AND HERBS. COMMON SPEEDWELL. Veronica officinalis L. Other common names.— Paul's betouy, ground-hele, fluellin, upland speedwell. Habitat and range. —This little herb frequents dry fields and woods from Nova Scotia to lilichigan and south to North Carolina and Tennessee. It also occurs in Europe and Asia. Description.— The common speedwell creeps over the ground by means of rather woody stems rooting at the joints and sends up branches from 3 to 10 inches in height. It is hairy all over. The leaves are opposite to each other on the stem, on short stalks, gi"ayish green and soft hairy, oblong or oval in shape, and about one-half to an inch in length; they are blunt at the apex, with margins saw toothed and narrowing into the stalks. From about May to July the elongated, narrow, spikelike flower clusters are produced from the leaf axils, crowded with small, pale-blue flowers. (Fig. 24.) The capsule is obo- vate, triangular, and com- pressed , and contains numerous flat seeds. The speedwell is a perennial belonging to the figwort family (Scrophulariaceir) . Collection, prices, and uses. — The leaves and flowering tops, which bring about 3 to 5 cents a pound, should be collected about Fig. 24.— Common speodwell (Vironica ofjficinulit), leaves and flowers. May or June. ^Mien fresh they have a faint, agreeable odor, which is lacking when dry. The taste is bitter and aromatic and somewhat astringent. Sl)eedwell has been used for asthmatic troubles and coughs and also for its alterative, tonic, and diuretic properties. LOXCLOVE. I>i(fit(iU,i purpurea L. Phannacopanal nairie. — Digitalis. Other common names.— Fur\)\e foxglove, thimbles, fairy cap, fairy thimbles, fafry fingers, fairy bells, dog's-finger, finger flower, lady's-glove, lady's-finger, lady's- thimble, poiidock, flap dock, floj) dock, lion's-mouth, rabbit 's-flower, cottagers, throat wort, Scotch mercury. 210 P1>ANTS FURNTSHTNO MEDICINAI. LEAVES AND HERB.S. 153 TTabitat and range. — Originally introduced into thi.s country from Europe as an orna- mental garden ])lant, foxglove may now be found wild in a few localities in parts of Oregon, Washington, and West Virginia, having escaped from cultivation and assumed the character of a weed . It occurs along roads and fence rows, in small cleared places, and on the borders of timber land. Description. — Foxglove, a liiennial or perennial Ix'longing to the figwort family (Scrophulariacea^), during the first year of its growth produces only a dense rosette of leaves, but in the second season the do\\Tiy and leafy flower- ing stalk, reaching a height of 3 to 4 feet, a])- pears. The basal leaves are rather large, with long stalks, while the upper ones gTadually become smaller and are borne on shorter leafstalks. The ovate or oval leaves, 4 to 12 inches long and about half as wide, the upper surface of which is dull green and wrinkled, are narrowed at the base into long winged stalks; the lower surface of the leaves shows a thick network of prominent veins and is grajdsh, with soft, short hau's. The apex is blunt or pointed and the mar- gins are round toothed. ^^^len foxglove is in flower, about June, it is a most handsome plant, the long terminal clusters Fig. 26. — Foxglove (Di, lit ills piirpurci), leaves and flowers. (about 14 inches in length) of numerous tubular, bell-shaped flowers making a very showy appearance. The individual flowers are about 2 inches long and vary in color from whitish through lavender and purple; the inside of the lower lobe is white, with crimson spots and furnished with long, soft, white hairs. (Fig. 25.) The capsule is ovoid, tM^o celled, and many seeded. Collection, prices, and uses. — The leaves, which are official in the United Slates Pharmacopoeia, are collected fi-om plants of the second year's growth just about the time that they are coming into flower. They should be very carefully dried in the shade soon after collection and as rapidly as possible, preserving them in dark, air- tight receptacles. The leaves soon lose their medicinal properties if not properlv dried or if exposed to light and moisture. Foxglove brings about 6 to 8 cents a pound. At present most of the foxglove or digitalis used comes to this country from Europe, where the plant grows wild and is also cultivated. Foxglove has a faint, rather peculiar odor and a very bitter, nauseous taste. Prepa- rations made from it are of great value in affections of the heart, but they are poisonous and should be used only on the advice of aphj'sician. 219 34 AMERICAN MEDICINAL LEAVES AND HERBS. SQUAW VINE. Mitchella re pens L. Other common namea. — Checkerberry, partridgeberry, deerberry, hive vine, squaw- berry, twinberrv, chickonberry, cowberry, boxberry, foxberry, partridge vine, winter clover, wild running box, oneberrj', pigeonberry, pnakebeiTy, two-eyed ber- ry, squaw-plum. Habitat and range. — The ^jquaw vine is common in woods from Nova Scotia to Minnesota and south to Florida and Arkansas, where it is generally found creeping about the bases of trees. Description. — This slen- der, creeping or trailing evergreen herb, a member of the madder family (Rubiacesc), has stems 6 to 12 inches long, rooting at the joints, and roundish- oval, rather thick, shining, dai'k-green opposite leaves about half an inch in length, whidi are blunt at the apex and rounded or somewhat heart shaped at the base, with margins entire. Sometimes the leaves show whitish veins. The plant flowers from about April to June, pro- ducing fragrant whitish, sometimes pale-pur]ilish, funnel-shajHHl and 4-lobed flowers, two borne to- gether on a stalk and having the ovaries (seed-bearing portion) united, resulting in a double, berry like fruit. These fruits are red and contain eight small, bony nutlets. (Fig. 20.) They remain on the vine through the winter and are edible, though practically tasteless. Collection, prices, andiises. — The leaves and stems (herb) are collected at almost any time of the j'ear and range in price from about 3i to 4 cents a pound . The leaves have no odor and are somewhat astringent and bitter. Squaw vine has tonic, astringent, and diuretic i:)roperties. 219 Fig. 20.— Squaw vino (Mitchella rcpcns), loaves and fruit.s. PLANTS f'URNlSHING MEDICINAL LEAVES AND HERBS. 35 LOBELIA. Lobelia inflata L. Pharmacopmal name. — Lobelia. Other common names. — Indian tobacco, wild tobacco, asthma weed, gagroot, void it- wort, puke weed, emetic herb, bladder pod, low belia, eyebright. Habitat and range. ^l.ohoViA may bo found in sunny situations in open woodlands, old fields and pastures, and along roadsides nearly everywhere in the United States, but especially east of the Mississippi River. Description. — -This pois- onous plant, an annual belonging to the bellflower family (Gampanulacece), contains an acrid, milky juice. Its simple stem has but few short branches and is smooth above, while the lower part is rough hairy. The leaves are placed alternately along the stem, those on the upper portion small and stemless and the lower leaves larger and borne on stalks. They are pale green and thin in texture, from 1 to about 2 inches in length, oblong or oval, blunt at the apex, the margins irregularly saw toothed, and both upper and lower surfaces fur- nished with short hairs. Lobelia may be found in flower from summer until frost, but its pale- blue flowers, while very Fig. 27. -Lobelia (Lobdia inflata). li'avcs, capsules. flowers, and inflated numerous, are very small and inconspicuous. They are borne on very short stems in the axils of the upper leaves. The lower lip of each flower has three lobes and the upper one two segments, from the center of which the tube is cleft to the base. The inflated capsules are nearly round, marked wdth parallel grooves, and contain very numerous extremely minute dark-brown seeds. (Fig. 27.) Collection, prices, and uses. — The Pharmacopoeia directs that the leaves and tops be collected after some of the capsules have become inflated. Not too much of the stemmy portion should be included. The leaves and tops should be dried in the Bhade and when dry kept in covered receptacles. The price paid for the dried leaves and tops is about 3 cents a pound. Lobelia has expectorant properties, acts upon the nervous system and bowels, causes vomiting, and is poisonous. The seed of lobelia is also employed in medicine. 219 36 AMERICAN MEDICINAL LEAVES AND HERBS. BONESET. Eupatorium -perfoliatum L. Pharmacopoeial name. — Eupatorium. Synonym.— Eupatorium connatum Michx. Other common names. — Thoroughwort, thorouia, are collected when the plants are in flower, stri])ped from the stalk, and carefully dried. They lose considerable of their weight in drying. The price per pound for boneset is about 2 cents. Boneset leaves and tops have a bitter, astringent taste and a slightly aromatic odor. They form an old and popular remedy in the treatment of fever and ague, as implied by some of the common names given to the j)lant. Boneset is also emploj-ed in colds, dyspepsia, jaundice, and as a tonic. In large doses it acts as an emetic and cathartic. 219 Fig. 28.— Boneset {Eupatorium perfoliatum), leaves and flowers. PLANTS I'UKNlSHlNt; M KDICI N AL LEAVES AND 1 1 KKBS. 37 GUM PLANT. (1) GrindeUa rohusLa Null.; (2) GnndcUu squarrosd (Pursh) Dimal. Pharmaco panel I name. — Grindelia. Other common names. — (2) IJroad-leaved gum plant, scaly grindelia. Habitat and range. — The gum plant (Grindelia robusta) occurs in the States west of the Rocky Mountainti, while the broad-leaved gum plant (G. s(piarrosa) is more widely distributed, being of common occurrence on the plains and prairies from the Saskatchewan to Minnesota, south to Texas and Mexico, and westward to California. Description . — The name "gum plant" is applied especially to Grindelia robusta on account of the fact that the entire plant is covered with a resinous substance, giving it a gummy, varnishedappear- ance. It is an erect per- ennial herb belonging to the aster family (Aster- ace*) and has a round smooth stem, about l^- feet in height. The leaves are pale green, leathery in texture and rather rigid, coated with resin and showing numerous trans- lucent dots, and are about an inch in length. In out- line they are oblong spat- ulate^that is, having a broad, rounded top gradu- ally narrowing toward the base — clasping the stem and with margins some- what saw toothed The plant branches freely near the top, each branch some- what reddish and termi- nating in a large yellow flower. The yellow flowers are about three-fourths of an inch in diameter, broader than long, and are borne singly at the ends of the branches. Immediately beneath the flower is a set of numerous, thick, overlapping scales (the involucre), the tips of which are rolled forward, the whole heavily coated with resin. 219 Fig. 29.— Scaly grindolia {Grindelia squarrosa), leaves and flowrrs. 38 A M ERI C A .\ M J: 1 ) U ■ 1 ^ A I .KAVES A^'D HERBS. The broad-leaved gum plant (Grindelia squarrosa) is very similar to G. robusta, except that it is smaller and less gummy in appearance. It is more sparintrly branched near the top and the branches seem more reddis^h. The leaves are also clasjiing, but they are longer, about 2 inches in length, and broader, thinner in texture and not rigid, and more prominently toothed. The smaller flower heads are generally longer than broad and have narrower involucral scales, the recurved tips of which are longer and more slender. (Fig. 29.^ Collection, prices, and uses. — The leaves and flowering tops of both species of Grin- delia are official in the United States Pharmacopoeia, and should be collected about the time that the flowers have come into full bloom. The price ranges from about 5 to 10 cents a pound, ^^'hile both spe- cies are official, the leaves and tops of Grindelia squar- rosa, being more prevalent, are generally used. The odor of grindelia is balsamic and the taste resinous, sharply aromatic, and slightly bitter. The drug is sometimes used in asthmatic and similar af- fections, as a stomachic, tonic, and externally in cases of poisoning by poison ivy. CAXADA FLEABANE. Leplilon canadense (L.) Britton. Synonym . — E rigeron canadensis L. Other common names. — Erigeron, h o r s e w e e d , mare's-tail, Canada erig- eron, butterweed, bitter- weed, cow's-tail, colt's-tail, fireweed, bloodstanch, hogweed, pridewecd, scabious. Habitat and range. — Canada fleabane is common in fields and waste places and along roadsides almost throughout North America. It is also widely distributed as a weed in the Old World and in South America. Description. — The size of this weed, which is an annual, depends upon the kind of soil in which it grows, the height varying from a few inches only to sometimes 10 feet in favorable soil. The erect stem is bristly hairy or sometimes smooth, and in the larger plants usually branched near the top. The loaves are usually somewhat hairy, the lower ones 1 to 4 int-hes long, broader at the top and narrowing toward the base, with margins toothed, lobed, or unbroken, while those scattered along the stem are rather narrow with margins generally entire. This weed, which belongs to the aster family (Asteracete), produces from June to November numerous heads of email, inconspicuous white flowers, followed by an abundance of seed. (Fig. 30.) 219 Fig. 30. — Canada LlL'al>arH' {Liiilihin C(fil!i(liiis( ;, llowriiii'^' lops. PLANTS FURNISHING MEDICINAL LEAVES AND HERBS. 39 Collection, prices, and uses. — The entire herb is \ise