£<* ^ Q r U. S. DEPARTMENT OF AGRICULTURE. "' °^ r '*^ BDREAD OF PLANT INDUSTRY -BULLETIN NO N-0 1!. T. SALLOW W < hiej o/ Bureau. TILE SEEDS OF THE BU'KGRAS f. THE GERMINATION, GROWEfG, HANDLING, AND ADULTERATION OF BLUEGRASS SEEDS. By Edgar Brown, Botanist in Chargt of Seed Laboratory. 11. DESCRIPTIONS OF THE SEEDS OF THE COMMERCIAL BLUEGRASSES AND TIIK1K IMPURITIES. By F. II. Hillman, Amslant Botahist, Seed Laboratory. [881 ED NOVEMBER 14, 1905. / OF FL LIB. DOCUMENTS DEPT. ::.::-:-.: i^BMHlMy eposh WASHINGTON: GOVERNMENT PRINTING OFFICE. 1 905. BULLETINS OF THE BUREAU OF PLANT INDUSTRY. The Bureau of Plant Industry, which was organized July 1, 1901, includes Vege- table Pathological and Physiological Investigations, Botanical Investigations, Farm Management (including Grass and Forage Plant Investigations), Pomological Inves- tigations, and Experimental Gardens and (hounds, all of which were formerly sepa- rate Divisions; and also Seed and Plant Introduction and Distribution; the Arlington Experimental Farm; Investigations in the Agricultural Economy of Tropical and Subtropical Plants; Drug and Poisonous Plant Investigations; Tea Culture Investi- gations; the Seed Laboratory; and Dry Land Agriculture and Western Agricultural Extension. Beginning with the date of organization of the Bureau, the several series of Bulle- tins of the various Divisions were discontinued, and all are now published as one series of the Bureau. A list of the Bulletins issued in the present series follows. Attention is directed to the fact that "the serial, scientific, and technical publica- tions of the United States Department of Agriculture are not for general distribution. All copies not required for official use are by law turned over to the Superintendent of Documents, who is empowered to sell them at cost." All applications for such publications should, therefore, be made to the Superintendent of Documents, Gov- ernment Printing Office, Washington, D. C. No. 1. The Relation of Lime and Magnesia to Plant Growth. 1901. Price, 10 cents. 2. Spermatogenesis and Fecundation of Zamia. 1901. Price, 20 cents. 3. Macaroni Wheats. 1901. Price, 20 cents. 4. Range Improvement in Arizona. 1902. Price, 10 cents. 5. Seeds and Plants Imported. Inventory No. 9. 1902. Price, 10 cents. 6. A List of American Varieties of Peppers. 1902. Price, 10 cents. 7. The Algerian Durum Wheats. 1902. Price, 15 cents. 8. A Collection of Fungi Prepared lor Distribution. 1902. Price, 10 cents. 9. The North American Species of Spartina. 1902. Price, 10 cents. 10. Records of Seed Distribution and Cooperative Experiments with Grasses and Forage Plants. 1902. Price, 10 cents. 11. Johnson Grass. 1902. Price, 10 cents. 12. Stock Ranges of Northwestern California. 1902. Price, 15 cents. 13. Range Improvement in Central Texas. 1902. Price, 10 cents. 14. The Decay of Timber and Methods of Preventing It. 1902. Price, 55 cents. 15. Forage Conditions on the Border of the < treat Basin. 1902. Price, 15 cents. 16. A Preliminary Study of the Germination of' the Spores of Agaricus Campes- tris and Other Basidioinvcetous Fungi. 1902. Price, 10 cents. 17. Some Diseases of the Cowpea. 1902. Price, 10 cents. 18. Observations on the Mosaic Disease of Tobacco. 1902. Price, 15 cents. 19. Kentucky Bluegrass Seed. 1902. Price, 10 cents. 20. Manufacture of Semolina and Macaroni. 1902. Price, 15 cents. 21. List of American Varieties of Vegetables. 1903. Price, 35 cents. 22. Injurious Effects of Premature Pollination. 1902. Price, 10 cents. 23. Berseem. 1902. Price, 15 cents. 24. Unfermented Grape Must. 1902. Price, 10 cen.ts. 25. Miscellaneous Papers: I. The Seeds of Rescue < irass and Chess. II. Saragolla Wheat. III. Plant Introduction Notes from South Africa. IV. Congres- sional Seed and Plant Distribution Circulars. 1903. Price, 15 cents. 26. Spanish Almonds. 1902. Price, 15 cents. 27. Letters on Agriculture in the West Indies, etc. 1902. Price, 15 cents. 28. The Mango in Porto Pico. 1903. Price, 15cenis. 29. The Effect of Black Rot on Turnips. 1903. Price, 15 cents. 30. Budding the Pecan, 1902. Price, 10 cants. 31. Cultivated Forage Crops of the Northwestern States. 1902. Price, 10 cents. 32. A Disease of the White Ash. 1903. Price, 10 cents. [Continued on page 3 of cover.l U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF PLANT INDUSTRY BULLETIN NO. 84. li. T. GALLOWAY, Chitf oj But Til K. SHEDS OF THE BLUEGRASSES. I. Till'. GERMINATION, GROWING, HANDLING, AND ADULTERATION OF HI. I EGRASS SEEDS. By Edqak Brown, Botanistin <'lt'irij< of Seed Laboratory. II. DESCRIPTIONS OF THE SEEDS OF THE COMMERCIAL BLUEGRASSES AND THEIR IMPURITIES. By !•'. II. IIii.i.man, Assistant Botanist, Seed Laboratory. Lssi ed November 14, 1905. WASHINGTON: GOVERNMENT PRINTING OFFICE, 1 !» 1 1 ;, . BUREAU OF PLANT INDUSTRY. B. T. GALLOWAY, Pathologist and Physiologist, and Chief of Bureau. VEGETABLE PATHOLOGICAL AND PHYSIOLOGICAL INVESTIGATIONS. Albert F. Woods, Pathologist and Physiologist in Charge, Acting Chief of Bureau in Abst nee of Chief. ]•>< >TANICAL INVESTK iATK >NS. Fkederick V. Coville, Botanist in Charge. FARM MANAGEMENT. W. J. Spillman, Agriculturist in Charge. POMOLOGICAL INVESTIGATIONS. G. B. Brackett, Pomologist in Charge. SEED AND PLANT INTRODUCTION AND DISTRIBUTION. A. J. Pieters, Botanist in Charge. ARLINGTON EXPERIMENTAL FARM. L. C. Corbett, Horticulturist in Charge. INVESTIGATIONS IN THE AGRICULTURAL ECONOMY OF TROPICAL AND SUBTROPICAL PLANTS. < >. F. Cook, Bionomist in Charge. DRUG AND POISONOUS PLANT INVESTIGATIONS. AND TEA CULTURE INVESTIGATIONS. Rodney H. True, Physiologist in Charge. DRY LAND AGRICULTURE AND WESTERN AGRICULTURAL EXTENSION. Carl S. Scofield, Agriculturist in Charge. EXPERIMENTAL GARDENS AND GROUNDS. E. M. Byrnes, Superintendent. SEED LABORATORY. Edgar Brown, Botanist in Charge. J. E. Rockwell. Editor. James E.Jones, Chief Clerk. SEED LABORATORY. SCIENTIFIC STAFF. Edgar Brown, Botanist in Charge. F. H. Hillman, Assistant Botanist. J. W. T. Duvel, Assistant. 2 'RANSMITTAL l'. 8. I >! I' \i; IMI N I i >l Ai.KH'1 III R] . 1W re \i <>i Plant Imh stri . ( )lTI< 1. <>!' THE ( 'llll'.F. Washington, />. <\. July /■'>. I nor,. Sir: I have the honor to transmit herewith and to recommend for publication a- Bulletin No. s l of the series of this Bureau the accom panying technical paper entitled "The Seeds of the Bluegrasses." This paper was prepared by Mr. Edgar Bi'own, Botanist in Charge of the Seed Laboratory, and Mr. F. 11. biillman, Assistant Botanist, Seed Laboratory, and has been submitted with a view to publication. The bluegrasses are among the mosl important forage plants in many sections of the United State- and Europe, and large quantities nf seed are harvested annually for use in (hi- country and for expor tat ion. The process of cleaning the seed of the bluegrasses for market is such that many of the distinguishing characters are lost, and separate descriptions are necessary for the hand-picked and commercial seed of the same species. The seeds of the differenl commercial species are so nearly alike in general appearance that at present none hut the trained observer can distinguish between them. This similarity of appearance has encour- aged the use of the cheaper and less desirable species, especially Canada bluegrass, for the adulteration of or substitution for the more expensh e species. The descriptions and illustrations herewith given of the bluegrasses and of their impurities will be of great value in furnishing seedsmen the necessary information to enable them to distinguish the different species. The accompany ing illustrations are necessary for a complete under standing of t he text. Respect fully, B. T. ( i \i.ii >\\ at, ( 'hiefqf Bui\ an. 1 Ion. .1 \mi> Wils< IN, Si • /■- tary of . Vgricultun . 3 Digitized by the Internet Archive in 2013 http://archive.org/details/bluegrassOOunit CONTENTS. I. Tin Germination, Growing, Handling, \m> Adulteration of Bi.i'k- ghass Seeds. By Edgar Brown • ' I (escriptii m ni commercial and hand-gathered seeds 9 Grades and quality of commercial seeds 10 Adulteration I" Weight per bushel II i termination 12 Growing and handling 12 /' a prati nsis | Kentucky bluegrass 12 Poa compressa (Canada bluegrass) 13 /•,„, irivialis i rough-stalked meadow grass i 13 Poa a, moralis . \\ I mead< >\\ grass i 13 Poa triflora (fowl meadow grass) 13 {'mi araehnift ra I Texas bluegrass) It I'mi annua (annual bluegrass ) 14 /',,./ nl in an (alpine meadow '_ r ra>s) 14 I'mi sudetica 11 II. Descriptions oi the Seeds of the Commercial Bluegrasses ^nd Their Impurities. By F. 11. Hillman 15 The bluegrasses 15 Key i" tin seeds of Ihe more common species of I'i>;i as found on herbarium specimens I s Key to commercial bluegrass seeds a tier preparation for market. . 1!' Comparison of the principal distinguishing characters of blue- grass seeds 20 Descriptions of species 22 Poa pratensis 1... Kentucky bluegrass, June grass 22 Poa compressa L., Canada bluegrass, Hat-stemmed bluegrass 24 Poa trivial is I.., rough-stalked meadow grass 21 Poa nemorai 'is L., wood meadow grass l'i; I'mi triflora Ehrh. i /'. flara I... /'. serotina Ehrh.), fowl meadow grass, false redtop 27 I 'in i arachnifera Tun-., Tex a- bluegrass 28 r >ni a a n I... annua] meadow grass 2!> Poa a! pi mi L., alpine meadow grass 29 Poa 1 1 at -like 30 Panicularia spp :; 1 Panicularia m rvata I Willd. ) Kuntze, nerved manna grass, s stimes called fowl meadow grass 3 1 Pa i ri i in rin ■inn i- 1,-, i mi i Tt irr. | MacM., reed meadow '_'ra?-s. water meadow grass, tall manna grass 31 5 6 CONTENTS. II. Descriptions op the Seeds of the Commercial Blueorasses and Their Impurities — ( Jontinued. Page. Weed seeds commonly found with commercial bluegrass seeds •">'_' Bursa bursa-pastoris (L.) Britton, shepherd' s-purse 32 Lepidium virginicum I.., peppergrass .. 32 ( i rastium vulgatum L., mouse-ear chickweed 32 Alsine media I.., ci nun chickweed 32 A /si m ■ 1 1 in mi in it (L. ) Britton 33 din I it us arvensis (L.) Robs., Canada thistle 33 Taraxacum taraxacum (L. ) Karst., dandelion 34 Matricaria inodora I.., scentless camomile 34 Hit fin- in in sp., hawk weed. 34 An/In inis rotitln L., dog fennel, mayweed 35 Ckenopodium album L., lamh's-quarters, pigweed 35 Plantago lanceolata I... rib-grass, buckhorn, English plantain 35 Rumex crispus L., curled dock 36 Rumex acetosella L., sheep's sorrel, sorrel 36 Veronica arvensis 1.., corn speedwell 36 J a in- ns tenuis Willd., slender rush 37 Juncoides campestre (L. ) Kuntze, lield rush 37 .1 n n mill \ s albida DC., wood rush 37 Carex cephalophora Muhl., oval-headed sedge 37 Ergot occasionally found in commercial bluegrass seed 38 Claviceps purpurea (Fr. ) Tul., ergot 38 ILLUSTR VTIOXS. TEXT FIGURES. fage. 1. A. spikelet of Poa 15 2. Unrubbed Kentucky bluegrass seed | Pou pratt wis 1 17 :;. Seeds of Kentucky bluegrass ( Poa prah nsis | 18 ■i. Differenl forms of commercial seeds ni Kentucky bluegrass pratensis ) 22 ■">. Commercial seeds of Canada bluegrass (Poa compressa) 21 0. Seeds of rough-stalked meadow grass I Poa trivialis) 25 7 Seeds of wood meadow grass 1 Poa nemoralis) 2 L'7. Seeds of rib-grase Plantago lanceolata 1. .",."> 28 Seeds of curled dock ( Rumex crispus) :>(> 29 Seeds of sun-el > l: :St; 30. Seeds of corn speedwell l Veronica ai 36 :il Seeds uf slender rush (Junrus tenuis) :;7 .-.Is of field rush > Juncoides ca M7 eds of wood rush I Juncoides alhida 1 37 'A Seeds of sedge ( ( 'arex cephalophora) 38 35. Ei ceps purpurea) of Kentucky bluegrass 38 7 B, P t.— 176. THE SEEDS OF THE BLUEGRASSES. IK GERMINATION, CROW INC. HANDLING, AND ADULTERATION OF BLUEGRASS SEEDS. By Edg \ r I Iri i\\ v Botanist in Chargi of Seed Laboratory. DESCRIPTION OF COMMERCIAL AND HAND-GATHERED SEEDS. Great difficulty is experienced in distinguishing the seeds of the species of Poa. It is especially importanl to be able to recognize them. a> the species vary greatlj in value and th< seed of one species is frequently substituted for that of another. The descriptions of the seeds of Poa already published have been largely those of complete or hand-gathered specimens. Bui the seeds of some kinds as they appear <»n the market are more or less broken and have losl many of their distinguishing characters. The process of cleaning often rubs off the web at the base of the seed and the bairs along the sides and breaks the tip. On this account descriptions based <>n specimens of perfect -reds are not to be relied upon in identifying certain commercial Poas. The mutilation of seeds during the process of cleaning is especially marked in home-grown seed of Kentucky bluegrass {Poa pratensis). Even tin' hand-gathered seed of rough-stalked meadow grass {Poa trivialis)\s frequently so much injured about the slender apex as to Increase greatlj the difficult} of distinguishing il from that of Ken tuck\ bluegrass. On the other hand, the commercial seeds of wood meadow Lira-- (/'"'//-///'//''///.viand fowl meadow grass {Poa triflora) retain much of the pubescence on the glume, often the web, and are usually not broken on the tip. It i- important that descriptions and illustrations to be used in prac- tical -eed testing be taken from the commercial as well as hand- gathered seed and be comparative in character. Those given in this paper have been prepared from both hand-gathered and commercial -eed. The term seed is here used in it- popular sense. 5813— NO. 84—05 2 9 10 THE SEEDS OF THE BLUEGRASSES. GRADES AND QUALITY OF COMMERCIAL SEEDS. The seeds of all species except Kentucky bluegrass are known to the American trade in only one grade. This is the so-called ••fancy" grade, which is based on relative cleanness and on the bright appear- ance of the seed. The quality of different samples passing under this grade name is not necessarily uniform, but among the more careful dealers a purity standard of from 80 to 90 per cent is usually maintained. The seeds of Kentucky bluegrass and of Canada bluegrass raised in this country arc usually much cleaner and freer from foreign seeds than the European-grown seeds of rough-stalked meadow grass, wood meadow grass, and fowl meadow grass. Kentucky bluegrass seed is commonly offered in two grades — "fancy," and '•extra-clean " or "extra-cleaned." The latter names are a survival of the time when the seed was hand cleaned and the "extra- clean " was the best seed on the market. With the advent of improved machinery the ''fancy" grade was established and it is now the only grade generally accepted by the intelligent purchaser. The "extra- clean" still on the market belies its name, .since it consists of the chaff or cleanings from the fancy seed, and consequently contains only light seed. Samples of "extra-cleaned" as offered usually contain less than 10 per cent of seed. In some cases the growers rind a sale for the rough or uncleaned seed after it has been passed through a feed cutter. In this condition it has very much the appearance of fine-cut straw with a large per- centage of chaff, and can be scattered over pastures and other areas, seeding them as effectually as could be done by the use of fancy reclcaned seed. If well cured, the germinating quality of such seed is excellent, and the mass contains from 60 to 7»> per cent of pure seed. Except for foreign trade the percentage of germination has lit tie to do with the price and grade of bluegrass seed. Aside from adulterated samples the purity of "fancy" seed of all species of bluegrass is usually good. Of the 2,887 samples of Ken- tucky bluegrass tested by the Zurich Seed Control Station from 1876 to L903 the average purity was 86.3 percent. Of the tilt samples tested in the Seed Laboratory of the Department of Agriculture dining the past year the average purity was 7r>.o - 2 per cent. ADULTERATION. The seed of Canada bluegrass (/'<>\ the bushel of II pounds, bul it is always weighed, nol measured. The cleaned seed is always sold by the pound. As the weighl per bushel of bluegrass seed depends directly on its purity. it is customary in quoting the price of "fancy' 1 seed to accompany it with a statement as to the weighl per bushel. rreatise on Permanent Lines Hunter. Chester, England, 1901. 12 THE SEEDS OF THE BLUEGRASSES. The foreign trade is much more critical than the domestic trade, and the seed exported usually weighs from 22 to 24 pounds per bushel, while the domestic trade is content with seed weighing from 18 to 20 pounds. The heavier seed costs more per pound than the lighter seed, since there is more labor in its preparation, but it is cheaper for the purchaser. GERMINATION. The germination of commercial bluegrass seed is often poor. At the Zurich Seed Control Station the average percentage from 3.< >♦'»<♦ samples of Kentucky bluegrass seed tested from 1876 to 1904 was 65 per cent, while 90s samples of Poa trivialis tested showed an average of 72 per cent. The quality of Kentucky bluegrass seed as respects germination appears, however, to be improving. Last year's tests at the Zurich station gave an average of 68 per cent, while a few years ago 50 per cent was considered fair or satisfactory. Only the best seed goes to Europe, and consequently the percentage of germination of that ottered in this country is low. As carefully cured seed will germinate from 80 to 90 per cent, the cause for the poor quality of commercial seed is doubtless to be found in the way it is harvested and cured." The usual process is to pile the freshly stripped seed in ricks, either outdoors or in barns. This mass heats quickly if not stirred often during the first few days. One pile left without stirring reached a temperature of 140 c F. in sixteen hours, killing all the seed. GROWING AND HANDLING. With the exception of our native western species, more or less seed of all the commercial Poas is gathered in Europe, where the\ r are found wild. The harvesting is done by hand from the natural mead- ows, woods, or other uncultivated areas. The seed is cleaned by hand and carried to market in small quantities and collected by dealers who supply the trade. The United States furnishes Europe with Kentucky bluegrass seed, and Europe furnishes the seed of rough-stalked meadow grass and wood meadow grass, as well as of the other commercial species of Poa used in this country. Poa pratensis (Kentucky bluegrass). — The bulk of the Kentucky bluegrass seed comes from a limited area known as the bluegrass region of Kentucky. The counties of Bourbon, Scott, Fayette, Clark, and Woodford furnish most of it, although there is a small quantity saved in Shelby County. Some is harvested in southwestern Illinois, and there is another area on the border between Missouri and Iowa where a considerable amount of ^hh\ is saved. The. seed is gathered from the natural woodland pastures as well as from those where it has «See Bulletin No. L9, Bureau of Plant Industry, "Kentucky Bluegrass Seed: liar- Vesting, Curing, ami Cleaning.'' GROWING ANH HANDLING. 13 been sown. It is customary to graze rattle on it nearly the entire year, a-* thc\ do not materially injure the crop of seed if they are kept out for two or three weeks immediately before gathering. The seed is harvested by pulling the beads <>ll with a stripper, the grass not being cut for hay. The cleaning is a rather difficult process, as it is necessary to rub the heads thoroughly in order to separate the seed from the web at the base. The last of the chaff and dirt which i- blown < nit 1 1 mill',:' tin- cleaning process is -oh I a- "ext ra-cleaned " seed. Poa compressa (Canada bluegrass). The seed of Canada bluegrass is mostly produced in the Province of Ontario, along the north shore of the eastern half of Lake Erie. The soil is a heavy clay on lime- stone. In this section Canada bluegrass is not sown, hut appears as a volunteer in any fields that are not kept under cultivation, making a thick growth and crowding out other grasses and weeds. It is nearly always found in wheat fields when the wheat crop is a partial failure. In this case the seed, ripening as it does at the same time as the wheat, i- thrashed with it and screened out in cleaning. Where the seed i- harvested alone the grass is (ait with a mowing machine and cured the same as ordinary hay. and afterwards thrashed with a clover huller or grain separator. The hay is bright green, even when not cut until after the seed is ripe, and is well liked by some farmers a- feed, while it is considered bard and of little value by others. A good crop is from 200 to 300 pounds of (dean seed per acre. There has Keen some demand for this seed in the Southeastern States under the name of Virginia bluegrass. The seed is easily cleaned, as it is comparatively free from wool at the base and does not require rub- bing, as does Kentucky bluegrass seed. No special machinery is used except rather long sieves to insure sufficient screening. Poa trimalis (rough stalked meadow grass). -The wholesale trade in the seed of rough-stalked meadow grass is largely confined to the city of Hamburg, Germany. The seed is collected in the neighbor- hood of that city and in the marshes of the Elbe. Seed of e-ood quality is also supplied from Denmark, where in one locality this grass is grown especially for seed, and it is said to yield as much as 400 pounds to the acre. The - I is stripped or the grass is cut and the seed allowed to after-ripen, when it is cleaned by hand. Poa nemoralis (wood meadow grass).- The seed of wood meadow grass is gathered by hand in the woods of Germany, and cleaned in the same manner as is the seed of Poa t ri ridl is. Poa tr'nln-'t (fowl, meadow grass). Though widely distributed throughout the northern portion of the United States, this species is chiefly a natural meadow grass of lowlands, and is usually SO mixed with sedges and other grasses that seed collection on a commercial scale ha- not thin I ai' been undertaken in this Country. The seed of this species on the market comes from Europe and is very poor. 14 THE SEEDS OF THE BLUEGRASSES. Prof. L. R. Jones, of the Vermont Agricultural Experiment Station, reports the seed production from a nearly pure stand of this grass as amounting to 6 bushels of lit pounds each per acre. A small plat yielded seed at the rate of over 7 bushels per acre. The seed is pro- duced abundantly and ripens evenly. In Vermont it is harvested in the latter part of July. The name fowl meadow grass is often applied to another lowland grass, Pa/nicularia nervata. Pan arachnifera (Texas bluegrass). — The seed of Texas bluegrass is gathered by hand in northern Texas. It is cleaned by rubbing between the hands, and, owing to the long, woolly hairs at the base of the seed, it is never "fancy clean." The best seed is produced on rich, black, waxy soil, and is ripe about May 1 to 15. Only a small quantity is gathered each year, and consequently it is high priced and can not be considered as a commercial seed at the present time. Poa annua (annual bluegrass). — The seed of the annual bluegrass is not on the market in this country, though the plant is common about dwellings, especially in the South and East, and ripens its seed throughout the summer. The seeds do not ripen evenly, the upper ones falling before the lower flowers have opened. The seed is gathered and used to some extent in Europe. Poa alpina (alpine meadow grass). — Alpine meadow grass is best known in Switzerland, where the seed ripens from the end of June to the middle of duly. The viviparous form can be propagated by scat- tering the buds during the hot weather. Poa sudetica. — The seed of Poasudetica, which is a European grass, is rare in the market, but is occasionally quoted by French and by German firms. It is sometimes mixed to some extent with the seeds of the meadow grasses, particularly water meadow grass {Panicvlaria ami ricana). In addition to the foregoing, other species of Poa occur in the western and northwestern United States, where they contribute to the native forage of the stock ranges. The seeds of these specie-.. however, are not found in commerce. II. DESCRIPTIONS OF THE SEEDS OF Till. COMMER- (1 \l. HI. I EGR \SSES VXD THEIR IMPURITIES. By F. II. Iln i max, Assistant Botanist, Seed Laboratory. THE BLUEGBASSES. The "seeds" of the species of Poa, or the bluegrasses, are the ripened florets or individual part- of the smaller clusters, or spikelets, of the general floral system of the plant. The number of florets in each spikelet varies from two to nine in the different "kinds of Poa cominonh found in commerce. There i- some variation in the num- ber of florets in the spikelets of each species. The florets separate readilj at maturity, ami well-cleaned samples of seed contain few w linlr or partial spikelets. A complete, mature -pikelet embraces, besides it- several florets, a pair of chaff} scales, termed empty glumes, between which the florets, oral least the lower ones, rest. The empty glumes, while somewhat I a i [.—A spikelet of Pou: a, stem of spikelet; />, empty ghinn tl floret, back view: a, callus; b, keel; c, intermediate veins; r', marginal veins; c, hyaline portion oi uluiin'. Ill oret, side view: a, callus; h, ruehilla segment; c, keel; '/. intermediate vein; e, marginal vein; /, margin of glume. IV. Single ment: b, mur- ginalfold; r.palea; il.V front view: ct, ruehilla segment; b, a floret; c, palcu \ I Carj opsis, or grail dissimilar, are keeled, acute, and one or three veined. The keel of each is usuall} hispid-ciliate above the middle. A portion of the stem of the spikelet often remains attached to the base of the empty glumes when these are found in commercial samples. Each mature, well-developed floi'et or seed consists of a carvopsis, commonh called grain, two inclosing scales which, together with the empty glumes, constitute the chaff, and a -lender appendage, t he rachilla segment. ( Fig. 1.) L5 16 THE SEEDS OF THE BLUEGRASSES. The caryopsis corresponds to an individual grain in wheat, rye, and barley, and consists almost entirely of the seed proper, to which is added only the thin wall of the seed vessel. This is intimately blended with the seed coat, the two forming the covering of the true seed. The caryopsis is spindle-shaped and of ten broadest between the middle and the base. It is often bluntly keeled along one face and more or less evidently grooved along the opposite face. In the commercial bluegrass seeds the grain is amber-colored or dull wine-colored and semitranslucent. The surface is finely granular and dull. The kernel of the seed forms that part of the grain within the seed and seed- vessel walls. It consists of the embryo and endosperm, the latter forming the greater part. The embryo is situated at the basal extremity of the grain and is evident externally as a small ridge, often within a slight depression, on the keeled face. The grain adheres along its grooved face to the palea in some species in which free grains are not common in well -cleaned commercial seed. The two chaffy scales of the floret differ chiefly in size, form, rela- tive position, venation, and texture. The larger one, called the flower- ing glume or simply the glume, incloses the edges of the other, termed palea. The grain rests between the glume and palea, its keeled face lying against the glume. The rachilla segment is at the base of the palea and opposite the glume. It is one of the articulating sections of the rachilla, or axis of the spikelet. The characters by which the different kinds of bluegrass seeds arc distinguished one from another are afforded by the glume, palea, and rachilla segment, and involve size, form, color, veins of the glume, form and texture of the apex of the glume, and the pubescence. The glume is stiffish and more or less pointed at the ends. Its base is marked by the presence of a small, somewhat knob-like appendage, the callus. The latter bears the scar of attachment of the floret and, in certain species, a more or less pronounced tuft of webby hairs. The back of the glume is more or less keeled along its longitudinal center. Besides the fold forming the keel, the edges of the glume are infolded along the marginal veins. The marginal folds often are most pronounced within and sometimes are confined to the lower half of the glume, in which event the upper margins usually diverge and become spreading or flaring at the apex. The keel is strongly arched length- wise in some species and in others is nearly straight. Five veins traverse the glume longitudinally; one occupies the keel, two are at the marginal folds and are termed the marginal veins, while the other two are situated midway between the keel and marginal veins and are called intermediate or, by some authors, lateral veins. The interme- diate veins exhibit considerable variation in distinctness in the differ- ent species. The vein occupying the keel extends to the apex. The apex and often the upper part of the lateral margins of the glume in ! II ! HI. I EGR ^SSES. 17 most species are thin and translucent, or hyaline. The extent of the hyaline portion of the apex has much to do with the form of the latter and is variable in the different species. The palea i- commonly more delicate in texture than the glume, heing partially hyaline. Il usually i- shorter than the glume, hut in some species equals or exceeds ii in length. The difference in length usually is most e\ ident in the lower florets of the spikelet. Tun veins traverse the palea lengthwise and nearly meel at it- apex. The mar- gins of the palea are more or less acutely infolded alone' these veins, which are called the keels of the palea. The keel- are mostly covered hy the glume in some species, while in others the} are almost wholly exposed. There i- some variation in this respect, however, among seeds of the -anie species. The apex of the palea i- often notched. The raehilla segment i- nearly cylindrical and usually somewhat curved. It is slightly expanded at the apex, which is obliquely trun- cate, it- terminal surface constituting the -car of at- tachment to the succeeding floret. Different florets in the -ante spikelet in certain species exhibit a marked variation in the length of the raehilla segment, which i- shortest in the lower florets and conspicuously longer in the terminal one. where it usually hear- an aborted florel a- a -mall, pointed appendage. The surface of the florets of different species of Poa is subject to considerable variation. Some florets are smooth, or glabrous; others bear numerous minute, stiffish haii'-. rendering the surface rough, or scabrous: and some have a tine, appressed pubescence covering a part of the surface. Most of the species have a more or less silky pubescence on the keel and mar- ginal vein- below the middle or somewhat higher on the keel. The intermediate veins are more rarely pubescent. The keel- of the palea are usually fringed with minute hair-. <>r are hispid-ciliate, I»ut in some species the\ are silky pubes- cent. The basal web is wholly wanting in some species and in others varies from a few libers to a copious tuft. It readily separates from the florel in most species. The raehilla segment i- usually smooth, but in some species it i- appressed pubescent. The presence of the hair- on the marginal vein- often necessitates that care lie used in examining the raehilla segment with respect t<> pubescence. (Fie-. 2.) The color of mature seeds varies from verv light brown to dark brown. Sterile seeds are usually lighter or -t raw colored. Immature seeds are more or less tinged with green; some are purplish. In cer- tain species the glume i- tinged with golden yellow near the apex. The aborted terminal floret and all the hairs are w hite. The raehilla segment i- lighter colored than the glume or palea. \.. -. 2. — ("nrubbed Kentucky blue- web; '.. pubi - marginal vein; •■, |. ii I..' - 1 18 THK SEEDS OF THE BLUEGRASSES. Poorly cleaned samples are apt to contain many sterile floret-. These are slender, sometime- shrunken, and usually lighter colored than the grain-bearing florets, which are comparatively plump and often dark colored, owing to the color of the grain appearing through the thin palea. (Fig. 3.) The recognition of the several species of Poa, when the identity is questionable, requires the use of a good lens and a knowledge of the principal distinguishing characters. A sample t . ky under examination should be spread thinly on bluegrass (Poa pratensis): a, a sheet of paper, or. better still, OD a black sur- grain bearing: 6, sterile. e awi i i" l *. i e lace. \\ ith a good light and means tor turn- ing the seeds over while under the lens, they can easily be examined with reference to size, color, distinctness of veins, character of pubes- cence, the condition of the margins of the glume, etc. Exposing the different sides of the florets to the light while under examination i> often absolutely essential in determining the nature of the veins and pubescence. KEY TO THE SEEDS OF THE MORE COMMON SPECIES OF POA AS FOUND ON HERBARIUM SPECIMENS. Basal web present. Web very persistent and conspicuous - /'. arachnifera. Web easily removed, small; keel of the glume pubescent. Intermediate veins distinct. Intermediate veins sharply defined as narrow ridges; glume margins narrow, not easily seen from the side; marginal veins usually smooth. /'. tririn ~ -j- j. C - 5 - ' TT "2 J a! ^ »; * — p. U ^ s K '2c o3 S oj w C , w CL, 2;c -T'Jc- ^ is 3J ^ 0>^ 4) t3 a = r x * zz -5 'S E i - a, 5 i. =s a, H X X j. i. w - . , , • y: - ■/ -j ■ ' V ~ w — — - - t- ~ - C £ £ ■ t V % B ■ ■5 2~ s B a a; is £ C fcH " O ij o3 a "3 •o - * if is - x .B -3 M s .2 i-js a si — ■ af X af J. s-§B d - jj s o a ■ s : ' : a • ^ = c ^ - - 3g 1= " 1 ■=.; - '7 r - i a._ c - 'H - - 7 •S • if u l'g.S-3 1 1) *j ^ : : f S =1 o 1 X ,M C B o 5*7.2 to ~" 5 a S « c = ; ■j. " 3 a .s a) ■"■ fi istinct; n nt sharply de- fined, slen- der ri d ges; smootli. ndistinct or appare ntly w ami ii g; smooth. ha r ]il y de- fined as slen- der ridges; smooth. — X B | oi S M H >-> 33 M cw X _ ft < ill ■~ i.6 z - - c - ^ tuse; to fi a r i n comme seed. Acute: i ly hyi edged a tire;■ '1/3.. OS B a - b 1-- ~ i B » OS E - ; a e r: S E 2) ~ o — ic ~ .■ r»*JC -v OS QJ t 2 c - r - lis 5 o"S - - ' O a *" ►J X ri ri CO CN i|)-U.r| ~~' i c-J i 7-1 "' fi -5 »L 5 tag 5 .. 1 ^ J. t- : M ri .•'.* y. a; '3 | £5 - 5 - ft « ,s S X A 2 i s i ^1 &; a; a; a; COMPARISON <»F DISTINGUISHING CHARACTERS. •_'l ~ St r -' u - = — ■■ — Z Jz'Z — - - - _£ ~_ -*~'Z i - : 7 — / — ,G - ■- -^. - : •*•* - Z ~X j 7 mS2 -' - I bJL £ " - = 7 ■ -H:" - — r ~ — — ■' — — T -7- S2-S 3 - = Z. jj - : a x 'i 1 i- - - x r - — - — -= St— s H '- u - - ,Q .- /. St 1 2 _= — 3 ~ s, *-» o C c 1 — - — _ • / — EJ* - i = * st s I-fl £ _ S: £ - — ir - r - 5ii-§z X &. — — -■ V. V, X. cj '.-- a - - \ - - i .- _ ■8^4: - - _ 7 5'".~; ^ 5 &J: > _ st — a — a «, t. . ~ >. = / 2 - 1. * '5 - ;i j- a = = : - > ^ STT = d £ ? / C " * *" * ~ ** - ■?.-'-' - r "_ S - 2 .a s ^2-c 5 r.zi SI _ ' st . - - - c c 2 7 i =t "- i i — i ~ Sv /. 7 L - ||iii| sS|=l 22 THE SEEDS OF THE BLUEGRASSES. DESCRIPTIONS OF SPECIES. Poa pratensis L. KENTUCKY BLUEGRASS, .TUNE CRASS. Spikelets 3-5 flowered; florets 2— 2| mm., rarely 3 mm., long, lanceolate or fusiform as viewed from the back, lanceolate or ovate-lanceolate as viewed from the side, mostly acute <>r the terminal floret sometimes acuminate at the apex, glabrous between the veins, varying from light brown to dark brown, sometimes tinged with purple, sterile florets lighter; glume usually sharply keeled quite to the apex and often strongly arched, particularly at the base; its marginal folds comparatively broad, extending from the base nearly or quite to the apex, becoming hyaline-edged above the middle in the lower florets, usually not expanded or flaring at the apex, tin' edges nearly meeting in sterile florets, separated and usually distended forward in fertile lower florets, often scarcely covering the palea keels of fertile terminal florets, the hyaline edge more or less torn away and the margins jagged at the apex in rubbed commercial seed; intermediate veins distinct and glabrous; keel and mar- ginal veins silky pubescent below the middle or somewhat higher on the keel; basal web well developed; pubescence and web wanting, except occasional traces of the former, in well-rubbed commercial seed; palea nearly or quite as long as the glume, its keels finely hispid-ciliate and usually covered for the greater part of their length by the margins of the glume; rachilla segment slender, glabrous, varying from about one-sixth of the length of the glume in the lower florets to one-half its length in the terminal one; aborted floret of the sterile rachilla segment minute; grain li mm. long, somewhat keeled and grooved, often broadest below the middle, reddish brown or darker about the embryo, ami semitranslucent. 'Fig. 4.) Fig. I.— Different forms of commercial seeds of Kentucky bluegrass Poa pratensis : a and b, bael views; <■-/, side views: g-j, front views; /, a terminal floret. Commercial Kentucky bluegrass seed is mostly free from the silky and webby hairs present in hand-gathered samples, owing to 1 he rubbing process to which it is subjected before being marketed. The severe rubbing results in more or less injury to the thin margins of the glume, particularly at the apex, which is usually found to be more or less torn when examined with a lens. Seeds of a well-rubbed sample do not tend to cling in. small hunches as do those which arc unrubbed or hand-gathered. Well-developed seeds are rather robust and have the glume margins well separated and evidently distended forward. Sterile seeds, or such as have the grain wanting or poorly developed, are generally lighter colored, slenderer, and more compressed, while the glume margins more nearly meet and arc but slightly or scarcely distended. Such are much lighter in weight than well-developed seeds and consequently are mostly blown out with other chaff in well cleaned seed. DES< RIPTI0N8 01 SP] CIES. 23 Kentucky bluegrass seed is niosl readily confounded with thai of Canada bluegrass (Poa cimtpr&SHti) and rough -stalked meadow grass i/' - trivial is). Owing i<> the difference in cost, Poa eompresxa is sometimes mixed with or substituted for Kentucky bluegrass, while the latter is sometimes similarly employed with respect to Poa tri I'ialiit. The characteristic differences between Kentucky bluegrass seed and thai of Canada bluegrass, as exhibited by the bulk samples and l»y individual seeds under the lens, may be compared as follows: TCIO nil EGB ISS The usual, well-cleaned bulk samples are brown in color. Individual, well-matured seeds exhibit the same brown color of the bulk sam- pie. Nearly all the seeds taper from the cen- ter to both ends and are not broaderat the apex than at the base. The apes of commercial seeds ia usually torn, obtusely pointed, keeled, and scarcely hyaline. The intermediate veins are almost in- variably distinct, Canada blcegb Average samples lighter colored than I hose of Kentucky bluegrass. The lighter color of individual see. Is af- fords the principal character for the preliminary recognition of these seeds in mixtu i Must of the seeds are broaderat the apex than at the base, often distinctly broader at the apex than at the middle. Apex of commercial see. Is often torn, mostly expanded or. flaring, often but Slightly keeled. The intermediate veins are very indis- t incl or apparently wanting. A number of the samples of Kentucky bluegrass seed examined con- tained seed of the Canada bluegrass. As the latter seed found in com- merce usually contain- the prickles or even the seeds of Canada thistle (Carduus arvensis), these are often found in samples of Kentucky blue- grass seed containing the ( -anada bluegrass seed. Their presence indi- cates the admixture, since the Canada thistle does not grow in the seed producing localities of Kentucky, while it is abundant in Canada, where the Canada bluegrass is produced. Samples of pure Kentucky bluegrass seed are apt to contain the prickles of horse nettle < Solan um carolineme), sometimes wrongly called bull thistle, a prickly plant common in the bluegrass region of Kentucky. These prickles tire similar to those of the Canada thistle, but may be distinguished, as shown hereafter in this paper in describing the impurities of the blue- grass seeds. The fact that Canada bluegrass only begins to flower at the time Kentucky bluegrass is ripe precludes the possibility of the mixture of the two kinds of seed owing to the fact of growth toe-ether. Such mixture can occur only after the seed is gathered, through acci- dent or intent. 24 THE SEEDS (>F THE !!LI'Ki ; KASSKs. Poa coinpressa L. CANADA BLUEGRASS, FLAT-STEMMED BLX'EGRASS. Spikelets 3-9 flowered; florets2-2£ mm. long, oblong-obovate or the terminal one lanceolate as viewed from the back, somewhat narrowly oblong as viewed from the side, obtuse or the terminal one acute, smooth between the veins, straw colored or light brown; glume somewhat arched, especially at the base, and strongly keeled at the back, the keel often less pronounced at the apex than at the base: margins infolded from the base for about three-fourths the length of the floret in the lower florets ami nearly to the apex in the upper ones, hyaline-edged above the middle, often broadly so at the apex, which is more or less flaring in the lower florets, the thin apex often torn and jagged in commercial seed; intermediate veins very indis- tinct or not evident, glabrous; keel and marginal veins silky pubescent below the mid- dle; basal web present, slight; palea nearly or quite equaling the glume, finely hispid- ciliate on the keels, which are usually more or less exposed above the middle, sometimes from the base; rachilla segment glabrous, varying from about one-fifth the length of the glume in the lower florets to one- half its length in the terminal one; aborted floret of the sterile rachilla segment min- ute; grain 1-1 J mm. long, keeled and slightly grooved, s e m i t ra nsl ucent . ( Fig. 5. I The seed of Canada bluegrass is the cheapest of the bluegrass seeds, and is therefore, not adulterated with other Poas, although it is itself used as an adulterant to a considerable extent. Pure samples of Canada bluegrass seed almost always contain the prickles and sometimes the seeds of Canada thistle (Cardans arvensis)\ therefore, the occurrence of these prickles with other kinds indicates the use of this species as an adulterant. Their occurrence with seed of Poa trivial')* without evidence of the presence of Canada bluegrass seed is noted under the discussion of /'. trivialis. i"iG. 5. — Commercial seeds oi Canada bluegrass {Poa compressa) : a and 6, buck views; c-e, side views; f-i, front viewsof florets; i, a terminal floret. Poa trivialis L. ROUGH-STALKED Mi:\l>ow GRASS. Spikelets 2 or 3 flowered; florets 2-21 mm., rarely 3 mm., long, narrowly lanceolate or the fertile terminal one ovate-lanceolate as viewed from the back, usually lanceolate and curved as viewed from the side, laterally compressed as compared with other spe- cies, straw colored or light brown and sometimes purplish, sharply keeled, the l<> *1 somewhat arched; margins of the glume scarcely or but slightly distended, narrowly and rather sharply infolded nearly or quite to the apex, which is hyaline-edged, very acute and rarely expanded; intermediate veins very distinct as narrow and sharply defined ridges; keel slightly pubescent below the mid. lie. or rarely smooth; marginal veins smooth or sometimes pubescent, basal web present: palea nearly equal to the glume, its keelssmooth or finely hispid-ciliate near the apex and mosth covered by the margins of the glume excepl in the larger terminal florets; rachilla segment very slender, glabrous, varying from one-fourth to one-hall the length of the glume; gram I \ \ mm. long, keeled and grooved, scniitranslucent. reddish brown. I Fig. 6. | in 31 aiPTIONS OF 3PEOIES. 25 Rough-stalked meadow grass is chiefly band gathered; consequently tlic commercial seed is apt to bear more or less of the web as well as the silky pubescence on the keel. In man} 7 samples, however, both are rubbed awaj . This seed resem hies that of /'"■' pratensis and thai <>l Poa, compressa so closely that both are employed as adulterants, t he Fig. 6.— Seeds ,,f rough-stalked meadow friiss (Poa tririuli* : " and 6, former annarent I \ back views; • <-, side views; /and ■■" ial K I.N I I (KV BLUEGR ISS at Canada bli egrass I Poa romp) • Commercial seeds are usu- Commercial seeds rarely pubescent on the veins and ally pubescenl on the the webby hairs wanting; consequently mobile in bulk, keel vein, usually s tli not clinging in masses; unrubbed seed pubescent on on the marginal veins the marginal and keel veins. and bear mi ire or less of the webby hairs, conse- quently cling together in masses A- viewed from the side, Seeds mostly straight as Seeds straight, the glume the seeds are somewhal viewed from the side, margins somewhat evi- curved, much narrower glume margins often dent from the side, than the others, the strongly distended, glume margins usually only slightly evident. Apex of the glume usually Apex of the glume more or Apex of the glume often uninjured, strongly less tern in commercial torn, otherwise some- keeled, acute, slightly seed; keeled, sharph what keeled, obtusely hyaline-margined, often pointed, hyaline-edged pointed, broader than the curved. and not curved in un- base, hyaline-edged. rubbed seed. Intermediate veins sharply Intermediate veins d is- Intermediate veins indis- defined as narrow ridges. tinct as rather coarse tinct or apparently want- ridges, in ^r. Rachilla segment very slen- Rachilla segment coarser than in /'. trivialis &ad often der and less variable in verj short, length than iii /'. /ini- i, nsii • »r /'. compressa. 26 THE SEEDS OF THE BLFEfiRASSES. Poa nemoralis L. WOOD MEADOW 1. 1: \.-s. Spikelets 2 or 3 flowered; florets '2\~'l mm. long, lanceolate or ovate-lanceolate, mostly acute at the apex, light brown, sometimes yellowish tinged near the apex; glume rather broadly keeled and somewhat arched at the back; margins of the glume narrowly infolded quite to the apex or hyaline-edged and often flaring above the middle; intermediate veins very indistinct; keel and marginal veins silky pubescent below the middle; basal web slight; surface between the veins glabrous; palea nearly equal to the glume, evidently shorter in florets having a flaring apex, its keels hispid-ciliate and usually covered by the margins of the glume; rachilla segment varying from one-fourth to three-fourths of the length of the glume, the sterile rachilla segment very uniformly much longer than the others, more or less appressed pubescent, the pubescence somewhat variable and sometimes nearly want- ing; aborted floret of the sterile rachilla segment often one-half as long as the seg- ment; grain lij mm. long, rather slender, semitranslueent. (Fig. 7.) 7 3 7, r -j Fig. ' Seeds of wood meadow grass (Poa nemoralis): a-c, back views; mm. long. Seeds mostly narrower at the apex than at the cen- ter. Seeds usually yellowish at the apex. Intermediate veins usually evident but indistinct. Pubescence of the veins and the web often pres- ent in commercial seed. Rachilla segment mostly smooth, sometimes slight- ly rough, often two- thirds the length of the glume. Canada BLUEGKASS (Poa compressa). Seeds 2-2i mm. long. Seeds mostly broader at the apex than at the center or base. Seeds not yellowish at the apex. Intermediate veins indis- tinct or more commonly not evident. Pubescence of the veins and the web mostly absent in commercial seed. Rachilla segment smooth, not exceeding one-half of the length of the glume. Wood meadow grass (Poa nemoralis). Seeds 2j-3 mm. long. Seeds narrower or not broader at the apex than at the center. Seeds sometimes yellowish at the apex. Intermediate veins indis- tinct. Pubescence of the veins usually present in com- mercial seed. Rachilla segment pubes- cent or sometimes only rough, often three-fourths the length of the glume. The name fowl meadow grass is often applied, both by seedsmen and by writers upon grasses, to Punicularla nervata. Poa arachnifera Torr. TEXAS BLUEGRASS. Spikelets 4 or 5 flowered; florets 4-6 mm. long, narrowly lanceolate, acuminate, straw colored or light brown; glume strongly keeled quite to the apex and somewhat arched; margins narrowly infolded below and becoming broadly hyaline above the middle, not widely flaring at the apex; marginal and keel veins strongly pubes- / 9 Fig. 9. — Seeds of Texas bluegrass [Poa arachnifera): a and 6, back views, seeds showing the long hairs of the web; c and tl, side views; <-!//, a Fig i*. Seeds <>i mouse ear chickweed 1 1 '< rastium i ulgatum i; o, side views; 6, natural size of seeds, Alsine media L. COMMON CHICKWEED. Seeds circular-ovate, about 1 mm. in diameter with little variation in size, flattened with plane laces and flattened edges; scar in a small notch in the edge; surface dull. Slightly tubercled, the tubercles in rows on the edges and in more or less evidently WEED SEEDS FOUND WITH HI. I EGRA8S -111'-. 88 concentric rows "ii the similar fares; color brown, or reddish in immature seeds embryo cylindrical, curved aboul the endosperm, its extremities nearly meeting al the scar, i Fig. 19, «. i l ., media is very common in the United States, bul is so low-growing thai the American method of seed stripping prevents the occurrence of its seeds in abundance in commercial bluegrass seeds It- seeds are common in European bluegrass seeds, particularly those of rough-stalked meadow grass Alsine graminea t I-. ) Britton. a Fig. 19. — Seeds of chickweeds: a, Alsh ng, very slender, yellowish, usually expanded and lateralis flattened at the base, which con- sists of a portion of the leaf ti -sue and is darker Colored than the rest of the prickle, some w hat rounded oi angular in form and jagged-edged. I Fig. 21, cand d The prickles of horse nettle (Solanun tin, ns, i are coarser, I s mm. in length, light yellow in color, usually nol darker at the base. They are produced on the stems and the coarse midribs of the leaves, and i in breaking i iff ha\ e a transversely flattened scar. They occur fre- quently in sample-, of Kentucky-grown /'"" pratensia and are easily mistaken for those of Canada thistle. | Fig. 21, , natural size of seeds. wilD 81 l DS l"i N D w l 111 BL1 EGB V8 SI l D9. 35 Anthemis cotula I.. DOG FENNEL, MAYWEED. !- akenes cylindrical, broadly club-shaped, IJ-2 curved; suTface < lull and usualh roughened by man} small tubercles more or less distinctly arranged in ten rows, indistinctly few-tubercled or nearly smooth, but commonly more or less ■ ibbed; base tipped bj the rounded, whitish scar; apex rounded or slightly pointed; color varying from lighl to dark brown, i I ij Found occasionally, l>ui never abundantly, in both American and European bluegrass Beed. nun. long, straight <>r i Is of dog fennel I Anthemis eotula): a, side views; 6, natural size oi si eds Chenopodium album L. i vmb's-qd vrters, pigweed. Is nearly circular, lens-shaped, with blunt edges, l-lj nun. in diameter, occur- ring in commercial seeds as free seeds or as fruits, the seeds proper being invested by the thin pericarp; free si eds jet black, smooth hi- nearly so, and highly polished; sear occu- pying a curved groove extending from the cen- ter tn the edge of one face and usually e\ idenl as a light-colored line; fruits only slightly larger than tin- seeds, mostly gray or black and dull; pericarp wall often broken away, expos- ing theshining black surfaceof the seed; again, this wall and the seed coat are often broken, exposing the yellowish or whitish embryo and endosperm; embryo cylindrical, occupying the border of the seed and Burrounding the endosperm, its extremities almost meet- ing, the tip of the caulicle occupying an extension of the seed coal at the edge beside the sear. i Fig. L'li. ) Found chiefly in Kentucky bluegrass and Canada bluegrass seeds, but nut frequently and never abun- dantly. Plantago lanceolata L. b ' a Seeds of lamb's-quarti ilium album): a, various forms natural size of seeds. RIB-GB ISS, BCCKHORN, ENGLISH PLANTAIN. Seeds oval-oblong, I ; 3 nun. long, Battened, one \ views of seeds; b, natural si/'' oi seeds. faee convex, the other having a deep groove and fig. 27.— seeds of rib-i rounded, infolded edges which scarcely meet at one tagolanc front and back end; surface smooth or slightly uneven, shining in fresh seed, brown or somewhal amber-colored; scar situated at the tei i the grooved face; embryo straight, in the center of the endosperm, usually evidenl through the somewhat trans) .a rent endosperm and seed coat. When placed in water the seeds develop a coat of transparent mucilage. Small seeds are found t.i s extent in both American and European seed; more commonly in Kentucky bluegrass than in Canada bluegrass seed. 36 THE SEEDS OF THE BLUEGKASSES. Eumex crispus L. CURLED DOCK. Seeds (akenes) 1 i— 2A mm. long, triangular with equal faces and broadly ovate- lanceolate; color dark reddish brown; surface smooth, polished; apex acute; base obtuse, contracted, and narrowly truncate at the scar; edges narrowly margined; faces longitudinally concave in poorly developed seeds; true seed coat thin; embryo cylindrical, rest- ing in the center of one face of the endosperm; caulicle pointing to the base of the akene. (Fig. 28.) Found occasionally, especially in Kentucky blue- grass and in Canada bluegrass seeds; small, imper- FiG.i Seeds of curled dock (.Ru- fectly developed s.-cd more commonly found than mexcrispus): a, broad and narrow i„ i „ i tu • i i " ,i , ■, large, heavy seed. 1 heir sharply three-angled, forms; 6, natural size of seeds. " . ...... beechnut-like form distinguishes them trom other impurities, except one or two other kinds of dock. The docks are destructive weeds, and care should be taken to prevent the sowing of their seeds. Rumex acetosella L. SHEEP S SORREL, SORREL. Seeds (fruits) acutely oval, three-angled, with equal faces, 1-1$ mm. long; repre- sented in commercial seed by the seed-like akene only or by the akene covered by the thin, closely fitting perianth segments, which are six in number, three broad ones covering the sides of the akene and three small ones cover- ing the angles at the base; covered by the perianth, the seeds are finely roughened, dull, and red- dish brown; venation of the three broad segments evident; small segments at the basal angles often broken away; akenes but slightly smaller than when covered by the perianth, bluntly three-angled; surface smooth, somewhat polished, reddish brown or wine colored, often semitranslucent; angles dark at the apex; internal structure essentially the same as in Rumex crispus. ( Fig- 29. ) < )ne of the commonest impurities in commercial seed, found "in all seed of the cultivated bluegrasses. a e Fig. 29. — Seeds of sorrel (Rumex acetosella): a, b, and c, seed enveloped by the perianth; h. i Fig. 32 Found frequently in the seed of wood meadow ^r&ss ami of the Poa sudelica of European origin. Juncoides albida IK' Fig. 82.— Seeds of Beld rush coidet campextre): ", different \ leu v t>, natural si/'- of Beeds \\,1\ of the Beed reddish brown or wine- colored, often semitranslucent. (Fig. 33. Found in various species of European-grown blue- grass see. I. The usually smaller size, absence of the basal appendage, and more distinct and constanl red- dish-brown lateral ridge serve to distinguish these from the seeds of .fiincniilt s rmn/irntre. Carex cephalophora Muhl lase without an appendage of h Pig. 33.— Seeds of wood rush coides albid ■ rent \ iews; h, natural si/r of seeds. 0\ M -III IDEO -I I" I Seeds (akenes) Lj 2 mm. long, lens-shaped and broadly ovate, contracted at the base and tipped al the apes by a conical appendage the base of the style ; surface smooth and dull; color varying from lighl to .lark brown; apical appendage often broken away in seeds found in commercial samples; perigynium broadly ovate- lanceolate, plano-convex, the tapering extremity usually rough-edged and notched at 38 THE SEEDS OF THE BLUEGRASSES. the apex; surface sometimes slightly grooved or ridged lengthwise, otherwise smooth; color varying from light brown to greenish or dark brown. (Fig. '.'A.) Seeds of sedge (Carex) are found in both American and European bluegrass seed. Owing to the wide area of their production, the seeds of various species of Carex occur in commercial blue- grass seed. The seeds of Carex are fruits (akeues) and occur free or in- closed within a sac-like covering (the perigynium). Carex cephalophora is Fig. 34. — Seeds of sedge ( Carex cephaiophora) : a, seeds .1 , .• , • , . . ., 1 * the species most commonly found m inclosed by the iierigymuin; h ti.l r, seeds with . ' perigynium removed; cents. 45. The Physiological R61e Of Mineral Nutrients in Plants. L903. Price, 5 cents. 16. The Propagation of Tropical Fruit Trees and Other Plants. 1903. Price. 10 cents. 47. The Description of Wheal Varieties. 1903. Price, 10 cents. 18. The Apple in Cold Storage. 1903. Price, 15 cents. 40. The Culture of the Central American RubberTree. 1903. Price, 25 cents. 50. Wild Rice: Its I'ses and Propagation. 1903. Price, L0 cents. 51. Miscellaneous Papers: I. The Wilt Disease of Tobacco and Its Control. II. The Work of the Community Demonstration Farm at Terrell, Tex. III. Fruit Trees Frozen in 1904. IV. The Cultivation of the Australian Wattle. Y. Legal and Customary Weights per Bushel of Seeds. VL Golden Seal. 1905. Price, 5 cents. 52. Wither-Tip and < >ther Diseases of Citrous Tress and Fruits Caused by Colle- totricbum Glceosporioides. 1904. Price, 15 cents. 53. The Pate Palm. L904. Price. 20 cents. 54. Persian Gulf Dates. L903. Price, 10 cents. The Dry Rot of Potatoes. 1904. Price, JO cents. 56. Nomenclature of the Apple. 1905. Price, 30 cents. 57. Methods Used for Controlling Sand Dunes. 1904. Price, 10 cents. 5s. The Vitality and Germination of Seeds. 1004. Price, 10 cents. 59. Pasture, Meadow, and Forage Crops in Nebraska. 1004. Price, 10 cents. 60. A Soft Rot of the Calla Lily. L904. Price, lo cents. 61. The Avocado in Florida. 1904. Price, 5 cents. 62. Notes on Egyptian Agriculture. 1904. Price, 10 cents. 63. Investigations of Ku.-ts. 1904. Price. 10 cents. 64. A Method of Destroying or Preventing the Growth of Algse and Certain Pathogenic Bacteriain Water Supplies. 1004. Price, 5 cents. 65. Reclamation of Cape Cod Sand Dunes. 1904. Price, 10 cents. 66 Seeds and Plants Imported. Inventory No. 10. 1005. Price, 20 cents. 07. Range Investigations in Arizona. 1904. Price, 15 cents, us. North American Species of Agrestis. 1005. Price, 10 cents. 69. American Varieties of Lettuce. L904. Price, 15 cents. 70. The Commercial status of Durum Wheat. 1904. Price, 10 cents. 71. Soil Inoculation for Legumes. 1905. Price, 15 cents. 72. Miscellaneous Papers: I. Cultivation of Wheal in Permanent Alfalfa Fields. II. The Salt Water Limits of Wild Rice. III. Extermination of Johnson Grass. EV. Inoculation of Soil with Nitrogen-Fixing Bacteria. 1905. Price. 5 cents. 7:'>. The Development of Single-Germ BeetSeed. 1905. Price, 10 cents. 74. The Prickly Pear and Other Cacti as Food for Stock. L905. Price, 5 cents. 75. Range Management in the state of Washington. 1905. Price, 5 cents. 7