H. Marshall Ward

“ Although in the actual number of species the Grass family is by no means the largest in the vegetable kingdom, for there are far more Composites or Orchids, the curious sign of success in the struggle for existence comes out in grasses in that the number of individuals far transcends those of any other group, and that they have taken possession of all parts of the earth’s surface. Some species are cosmopolitan—e.g. our common Reed, Arundo Phragmites; while others—e.g. several of our native species of Festuca and Poa—are equally common in both hemispheres. ”

“ Even when three stigmatic plumes are developed, as in some Bamboos, close investigation does not confirm the view that the ovary consists of more than one carpel.
We must therefore regard the flower of the grass as typically composed of one carpel and three stamens, with no perianth whatever. It is subtended by one or more bracteoles (the lodicules) , and enclosed in a pair of bracteoles one higher than the other (the paleæ) . The glumes are bracts of the partial inflorescence—the spikelet. ”

“ The stigma of an ordinary grass consists of two divaricating plume-like structures composed of thin-walled cells. When the paleæ open these stigmatic plumes protrude, one on either side, and readily catch pollen shed from the dangling stamens and carried by the wind, and since the pollen of the same flower is usually shed at a time when the stigmas of many neighbouring plants are mature, there is every opportunity for cross-fertilisation. ”

“ If all the shoots are barren, the grass is a biennial in its first year of growth: if all have flowering stems in them, but show traces of old leaf-bases of the previous year, then the grass is a biennial in its second year. ”

“ It is impossible to avoid the question of variation in work of this kind, and students will without doubt come across instances—especially in such genera as Agropyrum, Festuca, Agrostis and Bromus—of small variations which show how impossible it is to fit the facts of living organisms into the rigid frames of classification. ”

“ Alopecurus pratensis, L. (Meadow Foxtail) . Large grass with stolons; very early, and much prized as pasture and hay, but soon dies out on light poor soils. Especially good for stiff soils. Sheaths long, ridged, brown or nearly black at the base as they age. Ligule distinct and obtuse,53 entire. Leaves numerous. Blades long, dark green, succulent and scabrous: ridges numerous and flat above, but distinct (Fig. 9) .
A. agrestis, L. in S. England has shorter leaves, and ridges not flattened; it is a troublesome pest of arable land, but does not usually invade pasture. ”

“ Alopecurus geniculatus is also a moisture-loving grass with strongly ridged leaves, but the interspaces are far less translucent and the whole habit is different.
All the other species of Aira have involute and setaceous leaves, and even A. cæspitosa is apt to roll in its leaves in mountain varieties, but they are easily flattened out, and show the ridges.
Psamma arenaria, Beauv. (Sea Mat-grass) . This is one of the most valuable “sand-binders," its long matted rhizomes holding loose sand together. It is a sea-shore grass, of no use for fodder. ”

“ The fruit is 167 flattened in the antero-posterior plane, and usually shines through the closely investing palea. A rachilla is visible. In Brachypodium the caryopsis is less flattened, and the apex tapers into the awn without teeth. In Lolium and Agropyrum the caryopsis is still more wheat-like and grooved.
All our Bromes are weeds, but some of them are important adulterants, requiring careful examination.
B. inermis is cultivated, and is a valuable grass. Awn short or wanting. Paleæ strongly 5-7 ribbed, inner with a marked central rib, closely adhering to caryopsis. ”

“ Ridges rounded, about twice as high as thickness between. Stomata more abundant above. Cuticle very thin and leaf soft. All bundles except the mid-rib with girders. Motor-cells fairly well developed between the ridges (Fig. 15) .
Kœleria cristata. Very hairy on both surfaces. Ridges irregular, the largest flat and high, the others rounded or triangular. Vascular bundles isolated, and the sclerenchyma reduced to a few cells in a single layer beneath the epidermis at the apex of each ridge and below the bundle. Motor-cells well developed in each furrow. Stomata more numerous above. ”

“ Agropyrum repens, Beauv. (Couch-grass) . A troublesome weed of arable land and gardens, &c., owing to the extraordinary vitality of its underground stolons. The young shoots are readily eaten by stock. Perennial, and extensively stoloniferous; bright or glaucous green. Blade thin, dry, rough edged, hairy and rough above, glabrous or hairy below. The short ligule fringed. Ears long, or sometimes short, pointed; often obliquely crossing in front of the sheath. Ridges inconspicuous. Hairs may be absent from the sheath, and nearly so from the blade. ”

“ Poa annua—though in some cases these ruderal plants indicate the presence of rotting substances, on ash-heaps and rubbish of various kinds.
With reference to the above, however, the student must not forget that very complex relations are concerned in changes of soil, shade, moisture, elevation, &c. and that although experienced observers can draw conclusions of some value from the presence of numerous species and individuals on a given soil, no one must conclude too readily that a soil is so and so, from observing solely that a particular kind of grass will grow there. ”

“ If all the shoots have flowering stems in them, and are evidently of the current year, the grass is an annual; but if any shoots have leaves only, it is either biennial or perennial: to determine which is not always easy, but in perennial grasses there will generally be evident remains of older leaf-bases and shoots, and if there are distinct underground stolons or creeping rhizomes as well the point may be considered decided, and the grass is perennial, as is the case with most of our important species. ”

“ The principal features of the Hordeum-grain are the closely adherent paleæ and angular fruit, the stiff awn appearing to come off from it as in Barley. The rachilla remains.
They are all weeds of no use in agriculture, though H. pratense is not uncommon in good pastures.
(2) Palea investing the caryopsis, often closely, but not fused with it, and its tip and awn quite free. ”

“ Aira is distinguished by the awn: Agrostis by the very different paleæ and caryopsis.
The other Poas are devoid of web, though they may have hairs below, and require very careful examination. The whole group is excessively difficult to deal with in “seed," and a special study of it is needed, since several species are important, and it forms a type.
(b) No web or pencil of hairs below the “seed."
(1) Apex of palea rounded, blunt, notched, or at most bluntly pointed, but with no trace of awn-or bristle-tip.
142
✲ Palea inflated, round-backed and somewhat winged, membranous. ”

“ Alopecurus pratensis has more depressed, flatter and broader ridges than Festuca, and a longer ligule, and lacks the pointed ears.
✲✲ Ligule whitish, membranous, long, or at least well developed. Sheaths not coloured or brown. Leaves thin and rough, at least at the base. Ridges not very prominent, but numerous and distinct.
Agrostis stolonifera, L. (Fiorin) . Stolons, with numerous short offsets bursting through the leaf-sheaths. Blade flat, rough, tapering, with rounded ridges, and convolute in bud: there are no auricles, but the blade may narrow, and form ledges, as it runs into the sheath. ”

“ The next point to notice is that not every grass has so many as two fertile flowers and one barren one in its spikelet, as the Oat has. A spikelet may have one (Phleum) , two (Aira) or three (Avena) or more (Poa) fertile flowers, and no barren ones or several, the number of flowers being counted by the number of pairs of pales found inside the pair of glumes. Moreover every flower is not necessarily fertile (e.g. Arrhenatherum, Holcus) and several grasses have one or more flowers in each spikelet containing stamens only—male flowers—while others may have ovaries only—female flowers. ”

“ The work is a many sided one, acting not only as a guide to the naturalist in the field, but also as a laboratory handbook, where the use of the lens and microscope may be employed to amplify the study of objects already observed in their natural habitats. ”

“ The whole theory of agriculture turns on this pivot, and the by no means3 small modicum of truth in such sayings as “All flesh is grass,” and that the man who can make two blades of grass grow where one grew before deserves well of his country, obtains a larger significance when it is realised that the only real gain of wealth is that represented by the storage of energy from without which comes to us by the action of green leaves waving in the sunshine. ”

“ Margins and keel rather rough.
These two species of Glyceria are distinguished by their shoot-sections and the ridges of the leaves of G. fluitans: they often occur in the same ditch.
They cannot readily be confused with others on account of their aquatic habit, and the characters given. The only other aquatic or semi-aquatic species are forms of Catabrosa, Digraphis, Arundo, Alopecurus geniculatus, Molinia cærulea and the rare Calamagrostis. ”

“ In Hordeum some of the glumes are so narrow and pointed as to resemble stiff awns. In Catabrosa the glumes are truncate, as if bitten off at the top.
The Paleæ are also often more or less boat-shaped, or flat ovate or oblong scales, usually more delicate than the glumes and frequently pointed, or (especially the outer pale) awned at the tip: in some cases, however, the awn springs from the middle or base of the back of the pale, and the latter may be bifid at its apex. The pale has usually a distinct middle nerve. ”

“ Alopecurus is very characteristic, and should be carefully examined as a type. A. pratensis is a valuable grass and said to be often adulterated with the undesirable A. agrestis, Holcus, &c. Arrhenatherum and Avena are easily distinguished by the basal hairs, rachilla, &c.
Fig. 68. Alopecurus pratensis. a, “seed," nat. size, and b, c, ditto, × 8; d, caryopsis, × 7. The “seed" here consists of the two glumes, connate below and hairy on the keel and ribs, including the caryopsis enveloped in a single palea with a dorsal awn. Note remains of stigma in d. ”

“ The lax spreading type of panicle characteristic of Aira and Agrostis, &c., described above, occurs in species of Avena, Bromus, Briza, Poa and Catabrosa, but the basal silky hairs and twisted awns (Avena) , long sub-terminal bristle-awns (Bromus) , habit 105 (Catabrosa) , and the presence of two, three, or more flowers in the considerably larger spikelets of all, easily distinguish them. ”

“ Sheath long. Ligule very long and bifid.
Elymus arenarius, L. (Sand Lyme-grass) . Like Psamma, this is a “sand-binder" and of no use for fodder. Leaves concave, and eared at the base of the blade: ears pointed and tend to cross in front. Ligule very short and obtuse. Ridges flattened above, not scabrid. Apex of blade rolled, forming a hard spine.
Psamma cannot easily be mistaken for the much less common Elymus, as it is not eared, and the ridges and ligule are very different.
(ii) Leaves not specially rigid and hard, and often thin; glabrous, or shining below. Ridges less evident. ”

“ In some species or varieties—e.g. Poa alpina, Festuca ovina—this viviparous condition may coexist with normal flowers and spikelets; in others—e.g. Poa laxa, var. stricta—only the viviparous state occurs.
In the following arrangement the student should note that the terms “Seed" and “Fruit" are used in the ordinary sense of the farmer and seedsman: by the former is meant the “seed" as it comes in samples into the market, when the true fruit or grain (Caryopsis) is almost invariably invested by adherent “chaff"—i.e. paleæ or glumes or both. ”

“ When the ears are well developed their points often cross one over the other in front of the sheath.
L. italicum, Braun. (Italian Rye-grass) , is an earlier and better variety for hay and sewage farms. Shoot more rounded in section, and has less marked veins on the more rolled leaf.
L. temulentum, L. (Common Darnel) , is annual and a weed of corn-fields. Foliage usually rougher.
Lolium perenne presents some difficulties in relation to such forms as L. italicum, species of Agrostis and Festuca, Alopecurus pratensis, Cynosurus and Agropyrum. ”

“ In Hordeum, for example, we never see the true fruit, the grain consisting of the caryopsis with paleæ so closely adherent to it, that we are apt to take them as part of the grain itself. The true seed, in the strict botanical sense, is never seen as a naturally separate organ in our native grasses ”

“ Moreover, the action of ruderal plants—including grasses—is to completely alter the nature of the poor soil and gradually fit it for other plants. Coverings of grass greatly affect the actions of heat and sunshine on the surface soil, and modify the effects of radiation and evaporation, to say nothing of the penetrating and other effects of the roots.
Rhizomes and stolons break up stiff soils; and every engineer and forester knows how useful certain grasses are in keeping the surface-soil from being washed down by heavy rains on steep hill-sides or embankments. ”

“ When the pollen-grain, having adhered to the hairy stigma, has begun to germinate, the resulting pollen-tube creeps down between the cells of the stigma, and hands over its enclosed nuclei to the embryo-sac, where fertilisation of the egg-cell is accomplished, by the fusion of one of the pollen nuclei with the nucleus of the egg-cell. ”

“ No hair on surface of leaves or sheaths.
✲ Margins of leaves smooth and even. Blades without ridges, a keel and flanking lines, acute, base rounded. Ligule of lower leaves very short.
Poa pratensis, L. (Smooth-stalked Meadow-grass) . An early and valuable dry pasture-grass, but though deep-rooted, it yields thin hay: its chief value is for "bottom grass" and in lawn mixtures, &c. Leaves stiff and pointed. Extra-vaginal rooting underground stolons, and intra-vaginal branches. Shoots smooth. Keel slight: seven principal veins and smaller ones between. ”

“ Ligule long and pointed, and often toothed at the margins. The leaves vary in breadth.
This and A. vulgaris, With. with shorter ligules, and, possibly, A. canina, L. with finer leaves, are varieties of52 A. alba, L. Only the variety A. stolonifera is of moderate value for pasture, especially on poor soils, as it lasts late into autumn: the others are weeds, like couch-grass.
Agrostis is full of difficulties for the beginner. The weed-forms often spring up after wheat has been cut, and count as “twitch," like Agropyrum. ”

“ Anthoxanthum, Alopecurus, &c.—and some care is necessary in examining grass “seed" in these circumstances (see p. 134) .
Interesting biological adaptations are met with in the distribution of grass “seeds." The very small and light125 fruits of Agrostis easily fall and are scattered by the wind, but in many cases the glumes (Holcus) or paleæ (Briza) are expanded and serve as “wings" offering extensive surfaces to the wind. In Arundo, Calamagrostis, Aira, &c., fine silky hairs attached to the rachilla serve a similar function, reminding us of the coma of true seeds and the pappus of Composites. ”

“ Again, A. stolonifera has a long, serrated, acute ligule, while A. vulgaris has a much shorter, entire and truncate one, and narrower leaves.
Agropyrum is the grass most likely to lead to confusion. Its ears, lower ridges, very short or obsolete ligule, and pubescence (sometimes glabrous) distinguish it.
Cynosurus sometimes gives trouble (see p. 50) with Alopecurus pratensis: the sheaths, ligule and flattened ridges should suffice for distinction. ”

“ Melica nutans, M. uniflora, and Calamagrostis Epigeios also come here.
⊙⊙ Motor-cells confined to the innermost 2-4 furrows. Sclerenchyma in a continuous band just inside the thick cuticle below.
Festuca duriuscula. The ridges are only about half to one-third as high again as the thickness between, and the motor-cells in four series at the base of the three innermost ridges. Each ridge has only one isolated sheathed bundle, without girders. Stomata on the flanks of the ridges, and few in number. The sclerenchyma forms a thick band just inside the strong cuticle below. ”

“ Considering their multifarious uses as fodder and food, for brewing, weaving, building and a thousand other purposes, it is perhaps not too much to say that if every other species of plant were displaced by grasses of all kinds—as many indeed gradually are—man would still be able to supply his chief needs from them. ”

“ An almost worthless grass, on sandy soils, but important as an impurity in Avena flavescens (see note, p. 158) .
Aira cæspitosa, L. (Fig. 44) .
The palea, about 2·5 mm. long, toothed above, has a fine straight hair-like basal awn not longer than itself. Caryopsis 1·3 mm., grooved. Rachilla distinctly hairy.
Easily distinguished when mixed with Poa nemoralis, &c.—e.g. by the awn, hairs on rachilla, &c. It requires scrutiny in regard to Agrostis, which also has no awn or basal hairs.
✲✲ No basal tuft, or merely a few short microscopic hairs below. Paleæ not bifid above. ”

“ Our other grasses have two, but often unequal in size.
In shape they are usually boat-like, pointed or obtuse (Briza) and frequently with a distinct keel (Anthoxanthum, Digraphis, Phleum, &c.) or with ridges, green lines (veins) and other characteristic markings (e.g. Digraphis) . The tip may be extended into a stiff long point or awn (Agropyrum, Phleum, Nardus) and the keel, ribs, and awn may have hairs or serrulæ on them. The rule is, however, that the glumes are not awned. ”

“ On dry hills a close tufted grass, with setaceous leaves, and in rich soils creeping and luxuriant with broad leaves. It is one of the few grasses that thrive in wet soils.
The chief points in the flat-leafed forms are the thin, dry leaves, rough on both sides and on the margins, with distinct raised ridges, and the base of the leaf narrowing suddenly into its insertion with the sheath, with no auricle, but with a long membranous ligule. The sheath not coloured, and the blade convolute. ”

“ As we shall see later the degree of inrolling of many grass leaves varies with circumstances.
In most others the blades are either flat (Figs. 8-12) , or more or less conduplicate on the mid-rib. The latter case occurs, for example, in grasses with flattened shoots, especially at the lower part of the blade—e.g. Lolium perenne, Dactylis, Glyceria, and some species of Poa, and the cross-section of the leaf below, just before it enters the sheath, is V-shaped. In Glyceria the leaf-bases may show yellow or brownish triangles. ”

“ Ridges are less prominent in Phleum pratense, Briza, Agropyrum, Triodia, Arrhenatherum avenaceum.
Leaves practically devoid of ridges.
26
In some grasses the tissue over the mid-rib is considerably raised and strengthened on the dorsal side of the blade as a “keel."
Keel more or less prominent.
Most grasses are glabrous, but there are a number in which hairs are nearly always a prominent feature. It must be remarked, however, that with grasses, as with other plants, the character of pubescence is apt to vary with the situation. ”

“ Many Graminaceæ are pronounced xerophytes, the epidermis often being developed as a water-storing tissue, while the erect leaves roll themselves in intense light, the stomata being situated accordingly. The halophytic strand-plants Psamma arenaria, Elymus arenarius, Agropyrum junceum, and other Dune-species, as well as species of Aira, Festuca, Anthoxanthum, Stipa, Lygeum, Aristida, &c. are examples. The heath-grasses—e.g. Festuca ovina, Nardus stricta, Molinia cærulea—also come under this category. ”

“ These grass-carpets may be composed of nearly pure growths of a few species, or of very many different grasses and other herbage. They are common in Arctic regions, on Alps, and in temperate climates generally, where we know them as meadows, hay-fields, pasture and lawns.
The Bamboos in the wider sense have a physiognomy of their own, e.g. in India, and may drive out most other plants and form dense undergrowths or jungle of interlaced stems and leaves and thorny shoots. Similar growths occur on the Andes and elsewhere in South America. ”

“ On the other hand, luxuriant growths of tall grasses may do harm to young plants, by their action as weeds and especially as shade-plants; though foresters can employ them in the latter capacity, under restrictions, to shelter young trees from the sun. Again, too much dry grass near a forest offers dangers from fire; and it is a well known fact that certain injurious animals, e.g. mice and other vermin, are favoured by a covering of grass.
Graminaceæ are for the most part chalk-fleeing plants, in spite of the fact that certain species can grow in very thin layers of soil on chalk downs. ”

“ An excellent example of what may be done by applying such knowledge as exists of the habits of grasses, is afforded by the historic case of the planting up of shifting35 sand-dunes with species like Psamma arenaria, Elymus arenarius, Agropyrum junceum, &c. ”

“ Glyceria is longer and corn-shaped, and Briza usually larger. Anthoxanthum and Phalaris are easily distinguished. Agrostis is smaller and “corn-shaped." Certain species of Panicum present resemblances, but the enveloping paleæ, &c. are very different. Melica also occurs as “naked fruits,” but is rarely seen, and its colour and brilliant lustre distinguish it.
B. Glumes not cuspidate. “Fruit" not yellow.
(a) “Fruit" white, owing to the closely investing palea.
Milium effusum.
A common grass, but not often met with in “seed" grasses. It is eagerly eaten by birds. ”