Herbs, well marked by the stipules of the alternate leaves being in the form of membranous sheaths above the usually swollen joints of the stem (these obsolete in one Genus). Flowers usually perfect. Calyx 4-6-parted. Stamens 4-9, inserted on the base of the calyx. Stigmas 2 or 3. Ovary 1-celled, with a single ovule rising from the base, forming a little nutlet.
* Flowers involucrate. Stamens 9. Stipules obsolete.
1. Eriogonum. Involucre 4-8-toothed, the flowers exserted. Calyx 6-parted, coloured (yellow in ours), enclosing the achene. - N.W. only.
* * Flowers not involucrate. Stamens 4-8.
2. Polyg'onum. Sepals 5 (occasionally 4), often coloured and petallike, persistent, embracing the 3-angled (or sometimes flattish) nutlet or achene. Flowers in racemes or spikes, or sometimes in the axils.
3. Ru'mex. Sepals 6, the 3 outer ones herbaceous and spreading in fruit, the 3 inner (called valves) somewhat petal-like and, after flowering, convergent over the 3-angled achene, often with a grain-like projection on the back. Stamens 6. Styles 3. Flowers casually in crowded whorls, the latter in panicled racemes.
4. Fagopy'rnm. Calyx 5-parted, petal-like. Stamens 8, with8 yellow glands between them. Styles 3. Achenes 3-angled. Flowers white, In panicles. Leaves triangular heart-shaped or halberd-shaped.
1. E. fla'vum, Nutt. "Woolly throughout, a few inches high. Leaves oblanceolate. Umbel of 3-9 rays, on a naked peduncle. Flowers yellow, silky. - N.W.
* Flowers along the stem, inconspicuous, greenish-white, nearly sessile in the axils of the small leaves. Sheaths cut-fringed or torn.
1. P. marit'imum, L. (Coast Knotgrass.) Prostrate with stout stems, glaucous. Leaves thick, oval to narrowly oblong. Flowers in the axils of leaves, clustered. Stipules very conspicuous. Stamens 8. Achenes smooth and shining, projecting above the calyx. - Sea-coast.
2. P. avieula're, L. (Knotgrass. Goosegrass.) A weed everywhere in yards and waste places. Stem prostrate and spreading. Stamens chiefly 5. Achene 3-sided, dull. Stigmas 3. Leaves sessile, lanceolate or oblong. Var. erectum, Roth. (P. erectum, L.) is upright and larger, with broader leaves.
3. P. pamosis'simum, Michx. Erect or ascending, yellowish-green. Leaves lanceolate to linear, acute, very small above. Sepals mostly 6; stamens 3-6. Achene smooth and shining. - Chiefly westward; sandy places.
4. P. ten'ue, Michx. Stem slender, upright, sparingly branched, angled. Leaves sessile, narrowly linear, very acute, 3-nerved. Stamens 8. Achene dull black. - Dry soil and rocky places.
* * Flowers in terminal spikes or racemes, mostly rose-coloured or pinkish, occasionally greenish.
- Leaves not heart-shaped or arrow-shaped.
5. P. lapathifo'lium, L. Sheaths not fringed, stem nearly smooth, 3-6 feet high. Leaves long, tapering from near the base to a narrow point, rough on the midrib and margins. Spikes oblong to linear and erect or nearly so. Stamens 6. Styles 2. Achene flat or hollow-sided. - In muddy places along streams and ponds.
Var. incarnatum, Watson, has the spikes more slender and elongated, nodding.
Var. inca'num, Koch, is 6-12 inches high, with small leaves more or less flocculent-hoary underneath, and short spikes. Chiefly eastward and N. W.
6. P. Pennsylvan'icum, L. Sheaths not fringed. Stem 1-3 feet high, the upper branches and the peduncles bristly with stalked glands. Spikes thick, erect. Stamens 8. Achene flat. - Low open grounds.
7. P. Persiearia, L. (Lady's Thumb.) Sheaths with a somewhat ciliate border. Stem nearly smooth, a foot or more in height. Leaves with a dark blotch on the middle of the upper surface. Spikes dense, erect, on naked peduncles. Stamens 6. Achene flat or 3-angled, according as the stigmas are 2 or 3. - Very common near dwellings in moist ground.
8. P. amphib'ium, L. (Water Persicaria.) Spike of flowers dense, oblong, showy, rose-red. Stem floating in shallow water or rooting in soft mud, nearly glabrous. Leaves long-petioled, often floating. Sheaths not bristly-fringed. Stamens 5. Stigmas 2. - In shallow water, mostly northward.
9. P. Muhlenberg'ii, Watson, differs from the last in being rough with oppressed hairs all over. - Ditches.
10. P. Hartwright'ii, Gray, is distinguished from P. amphibium by its foliaceous and ciliate sheaths. - Muddy margins of ponds and lakes.
11. P.hydropiperoi'des, Michx. (Mild Water-Pepper.) Stem slender, 1-3 feet high, in shallow water. Leaves narrow, roughish. Sheaths hairy and fringed with long bristles. Spikes slender, erect, pale rose-coloured or whitish. Stamens 8. Stigmas 3. Achene 3-angled. - In shallow water.
12. P. acre, H. B. K. (Water Smartweed.) Sheaths fringed with bristles. Leaves transparent-dotted. Stem root-ing at the decumbent base, 2-4 feet high, in shallow water or muddy soil. Leaves narrow, taper-pointed. Spikes slender, erect, pale rose-coloured. Sepals glandular-dotted. Stamens 8. Achene 3-angled, shining. - Muddy soil or shallow water.
13. P. Hydrop'iper, L. (Common Smartweed or Water-pepper.) Sheaths and leaves as in the last, the leaves, however, larger. Spikes slender, nodding, greenish. Sepals glandular-dotted. Stamens 6. Achene dull. - Wet places.
14. P. Virginia'num, L. Calyx greenish, unequally 4-parted. Stamens 5. Styles 2, persistent on the flat achene. Flowers in long and slender naked spikes. Stem upright, nearly smooth. Leaves ovate or ovate-lanceolate, taper-pointed, rough-ciliate. Sheaths hairy and fringed. - Thickets, in rich soil.
- - Leaves heart-shaped or sagittate. Sheaths much longer on one side than on the other.
15. P. arifo'lium, L., (Halberd-leaved Tear-thumb) with grooved stem, halberd-shaped long-petioled leaves, flowers in short loose racemes, 6 stamens, and a flattish achene, is not uncommon on the Lower St. Lawrence; rare in Ontario.
16. P. sagittatum, L. (Arrow-Leaved Tear-thumb.) Stem 4-angled, the angles beset with reflexed minute prickles, by which the plant is enabled to climb. Leaves arrow-shaped. Stamens 8. Achenes 3-angled. - Common in low grounds, especially beaver-meadows.
17. P. Convol'VUlus, L. (Black Bindweed.) Stem twining, not prickly but roughish; the Joints naked. Flowers in loose panicled racemes, 3 of the calyx-lobes rigid in fruit. Leaves heart-shaped and partly halberd-shaped. Not climbing so high as the next. - Cultivated grounds and waste places.
18. P. dumetO'rum, L., var. scandens, Gray. (Climbing False Buckwheat.) Stem twining high, smooth; sheaths naked, 3 of the calyx-lobes winged in fruit. - Moist thickets.
19. P. cilino'de, Michx. Stem twining, minutely downy. Sheaths fringed at the base with reflexed bristles. - Sandy pine woods and rocky hills.
L. Dock. Sorrel. * Herbage not sour, nor the leaves halberd-shaped.
1. R. Orbicula'tus, Gray. (Great Water Dock.) Growing in marshes. Stem erect, stout, 5-6 feet high. Leaves lanceolate; not wavy-margined or heart-shaped, often over a foot long. Flowers nodding on thread-like pedicels. Valves nearly orbicular, finely net-veined, each with a grain on the back. - Wet places.
2. R. salicifo'lius, Weinmann, (White Dock) may be looked for in marshes on the sea-coast and far northward. The whorls of flowers are dense and form a very conspicuous spike, owing to the great size of the grains on the back of the valves.
3. R. verticilla'tus, L. (Swamp Dock.) Leaves lanceolate or oblong-lanceolate, not wavy, the lowest often heart-shaped. Stem tall. Fruit-bearing pedicels slender, club-shaped, abrubtly reflexed, several times longer than the fruiting calyx. Valves dilated-rhomboid, strongly wrinkled, each bearing a very large grain. - Swamps, common.
4. R. crispus, L. (Curled Dock.) Leaves with strongly wavy or curly margins, lanceolate. Whorls of flowers in long wand-like racemes. Valves grain-bearing. - Cultivated soil and waste places.
5. R. obtusifo'lius, L. (Bitter Dock.) Lowest leaves oblong heart-shaped, obtuse, only slightly wavy-margined; the upper oblong-lanceolate, acute. Whorls loose, distinct. Valves somewhat halberd-shaped, deeply toothed at the base, usually one only grain-bearing. - Waste grounds.
6. R. sanguin'eus, L. Leaves oblong-lanceolate, often fiddle-shaped, wavy-margined. Whorls distant, in long slender leafless spikes. Valves narrowly oblong, obtuse, entire. Veins of the leaf red or green. - Atl. Prov. chiefly.
7. R. marit'imus, L. (Golden Dock.) Low, slightly-pubescent, much branched. Leaves linear-lanceolate, wavy-margined, the lower auricled or heart-shaped at base. Flowers in whorls forming leafy spikes. Valves oblong, lance-pointed, each bearing 2-3 long bristles on each side, and a large grain on the back. - Sea-shore, Atl. Prov.
* * Herbage sour; leaves halberd-shaped. 8. R. Acetosel'la, L. (Field or Sheep Sorrel.) Stem 6-12 inches high. Flowers dioecious, in a terminal naked panicle. - A very common weed in poor soil.
1. F. eseulentum, Moench. (Buckwheat.) Old fields and copses, remaining after cultivation. Achene smooth and shining.
2. F. TartaP'ieum, Gaertn., has very small flowers, and a dull roughish achene. - Escaped from cultivation in a few places.