Part 7

SALICACEAE, the Willow Family

Trees or shrubs, with dioecious flowers in catkins.

1a. Leaves less than twice as long as broad, on petioles 3 cm. long or more --2.

1b. Leaves more than twice as long as broad, on petioles 2.5 cm. long or less. (The genus Salix, or Willow, contains about 30 species in Michigan, of which only the commoner are mentioned here. For the others the Manuals should be consulted.) --8.

2a. Petioles strongly flattened laterally --3.

2b. Petioles not flattened laterally --6.

3a. Leaves broadly ovate or nearly circular --4.

3b. Leaves broadly triangular or deltoid in shape --5.

4a. Leaves coarsely toothed =Large-toothed Aspen, Populus grandidentata.=

4b. Leaves finely crenulate or serrate =Quaking Aspen, Populus tremuloides.=

5a. Tree with narrow spire-shape crown =Lombardy Poplar, Populus nigra var. italica.=

5b. Tree with spreading crown =Cottonwood, Populus deltoides.=

6a. Lower side of leaf densely tomentose =White Poplar, Populus alba.=

6b. Lower side of leaf glabrous or nearly so --7.

7a. Petioles glabrous =Balsam Poplar, Populus balsamifera.=

7b. Petioles ciliate =Balm of Gilead, Populus candicans.=

8a. Trees --9.

8b. Shrubs --13.

9a. Petioles without glands --10.

9b. Petioles with glands --11.

10a. Petiole short (about 5 mm.), broad and flat =Black Willow, Salix nigra.=

10b. Petiole slender, about 10-20 mm. long =Peach-leaved Willow, Salix amygdaloides.=

11a. Leaves green beneath =Crack Willow, Salix fragilis.=

11b. Leaves pale beneath --12.

12a. Branches and twigs conspicuously drooping =Weeping Willow, Salix babylonica.=

12b. Branches and twigs not conspicuously drooping, yellow =Yellow Willow, Salix alba var. vitellina.=

13a. Shrubs of bogs --14.

13b. Plants of sand-dunes along the Great Lakes --15.

13c. Plants of dry upland hills --16.

13d. Plants of wet ground, river-banks, and swamps --17.

14a. Leaves densely white-tomentose beneath =Willow, Salix candida.=

14b. Leaves pale beneath but not tomentose =Willow, Salix serissima.=

14c. Leaves glabrous and green beneath =Willow, Salix pedicellaris.=

15a. Leaves linear =Willow, Salix longifolia.=

15b. Leaves ovate-lanceolate, tomentose beneath =Willow, Salix syrticola.=

15c. Leaves ovate-lanceolate, glabrous =Willow, Salix glaucophylla.=

16a. Leaves about 3 times as long as broad =Willow, Salix rostrata.=

16b. Leaves narrower, nearly sessile =Willow, Salix tristis.=

16c. Leaves narrower, distinctly petioled =Willow, Salix humilis.=

17a. Leaves linear or nearly so =Willow, Salix longifolia.=

17b. Leaves shining =Willow, Salix lucida.=

17c. Leaves silky =Willow, Salix sericea.=

17d. Leaves not as in the preceding 3 species --18.

18a. Leaves rounded at base =Willow, Salix cordata.=

18b. Leaves acute at base --19.

19a. Leaves finely serrulate =Willow, Salix petiolaris.=

19b. Leaves remotely serrate or nearly entire =Willow, Salix discolor.=

MYRICACEAE, the Sweet Gale Family

Shrubs, with monoecious or dioecious flowers in catkins, and aromatic foliage.

1a. Leaves pinnately lobed =Sweet Fern, Myrica asplenifolia.=

1b. Leaves merely serrate --2.

2a. Shrub of sandy soil, shore of Lake Erie =Bayberry, Myrica carolinensis.=

2b. Shrub of bogs and shores, northern half of state =Sweet Gale, Myrica gale.=

JUGLANDACEAE, the Walnut Family

Trees with alternate pinnately compound leaves and flowers in catkins.

1a. Leaflets 11-23; pith divided by partitions into chambers --2.

1b. Leaflets 5-11; pith not partitioned (Hickory) --3.

2a. Pith brown; bark with flat longitudinal ridges =Butternut, Juglans cinerea.=

2b. Pith cream-color; bark of trunk without flat ridges =Black Walnut, Juglans nigra.=

3a. Bark of the trunk essentially smooth, not deeply furrowed or shaggy --4.

3b. Bark of the trunk deeply furrowed or shaggy --6.

4a. Leaflets glabrous beneath; buds greenish --5.

4b. Leaflets somewhat pubescent beneath; buds bright yellow =Bitter Nut, Carya cordiformis.=

5a. Twigs hairy =Small-fruited Hickory, Carya microcarpa.=

5b. Twigs smooth =Pignut Hickory, Carya glabra.=

6a. Twigs and leaves both pubescent --7.

6b. Twigs nearly smooth; leaves smooth beneath =Shag-bark Hickory, Carya ovata.=

7a. Twigs brownish; buds densely hairy =Mocker-nut Hickory, Carya alba.=

7b. Twigs orange; buds very slightly hairy =King-nut Hickory, Carya laciniosa.=

BETULACEAE, the Birch Family

Trees or shrubs with alternate simple leaves and inconspicuous monoecious flowers, the staminate flowers in catkins, and the pistillate in catkins or small clusters.

1a. Trees, with white or yellowish bark exfoliating in thin papery plates or scales --2.

1b. Tree or shrub, with smooth, dark gray bark; trunk fluted with prominent longitudinal ridges =Hornbeam, Carpinus caroliniana.=

1c. Trees or shrubs; the bark more or less roughened, but not exfoliating; trunk not fluted --3.

2a. Bark white or chalky =Paper Birch, Betula alba var. papyrifera.=

2b. Bark yellowish =Yellow Birch, Betula lutea.=

3a. Shrubs, with leaves 4 cm. long or less --4.

3b. Shrubs or trees, with leaves 5 cm. long or more --5.

4a. Twigs glandular-warty =Dwarf Birch, Betula glandulosa.=

4b. Twigs not glandular =Swamp Birch, Betula pumila.=

5a. Twigs and bark with the odor of wintergreen =Sweet Birch, Betula lenta.=

5b. Twigs and bark without odor of wintergreen --6.

6a. Fruit clusters woody, persistent on the plant for a long time --7.

6b. Fruit clusters herbaceous, dropping in late autumn --9.

7a. Leaves rusty or whitish beneath, and pubescent at least on the veins =Speckled Alder, Alnus incana.=

7b. Leaves green beneath, and either pubescent or smooth --8.

8a. Leaves broadest at or below the middle =Mountain Alder, Alnus crispa.=

8b. Leaves broadest above the middle =Smooth Alder, Alnus rugosa.=

9a. Tree; fruit a cluster of bladder-like sacs each containing a small achene =Ironwood, Ostrya virginiana.=

9b. Shrubs; fruit a nut within a close-fitting involucre --10.

10a. Involucre of 2 broad bracts, almost separate and not much longer than the fruit =Hazel, Corylus americana.=

10b. Involucre of united bracts, prolonged into a bristly beak beyond the fruit =Beaked Hazel, Corylus rostrata.=

FAGACEAE, the Beech Family

Trees (or 1 species shrubby), with alternate simple leaves and monoecious flowers, the staminate flowers in catkins, and the pistillate solitary or in small clusters. Fruit a nut (or acorn) enclosed in a cup or bur.

1a. Leaves serrate with numerous sharp-pointed teeth --2.

1b. Leaves serrate, lobed, or entire, but never serrate with sharp-pointed teeth; fruit an acorn; pith 5-angled in the young twigs (Oak) --3.

2a. Bark gray, smooth; buds 3-4 times longer than wide; nut triangular =Beech, Fagus grandifolia.=

2b. Bark rough; buds relatively thicker; nut rounded =Chestnut, Castanea dentata.=

3a. Leaves entire, except for a bristle at the tip =Shingle Oak, Quercus imbricaria.=

3b. Leaves toothed or lobed, the points bristle-tipped --4.

3c. Leaves toothed or lobed, the points without bristles --10.

4a. Leaves entire below the middle, with a few shallow lobes beyond =Black Jack Oak, Quercus marilandica.=

4b. Leaves deeply lobed throughout --5.

5a. Cup of the acorn saucer-shape, covering less than one-third of the acorn --6.

5b. Cup of the acorn hemispherical or top-shape, covering one-third or more of the acorn --8.

6a. Length of the lateral leaf-lobes less than one-third the width of the leaf; acorn cup 2-2.5 cm. wide =Red Oak, Quercus rubra.=

6b. Length of the lateral leaf-lobes more than one-third the width of the leaf --7.

7a. Acorn depressed-globose, about 1 cm. in diameter =Pin Oak, Quercus palustris.=

7b. Acorn ovoid, 1.5-2 cm. thick =Schneck's Oak, Quercus schneckii.=

8a. Leaves pubescent beneath =Black Oak, Quercus velutina.=

8b. Leaves glabrous beneath --9.

9a. Buds glabrous; inner bark of the trunk yellow =Hill's Oak, Quercus ellipsoidalis.=

9b. Buds pubescent beyond the middle; inner bark of trunk red =Scarlet Oak, Quercus coccinea.=

10a. Leaves deeply pinnately lobed --11.

10b. Leaves crenate, dentate, or sinuate, not lobed --12.

11a. Leaf divided nearly to the middle by a pair of deep lateral lobes near the middle of the leaf; acorn more than half covered by the cup =Bur Oak, Quercus macrocarpa.=

11b. Leaf without a median pair of deeper lobes; acorn about one-fourth covered by the cup =White Oak, Quercus alba.=

12a. Leaves broadest at or near the middle, with numerous (8-13) sharp coarse teeth on each side =Yellow Oak, Quercus muhlenbergii.=

12b. Leaves broadest above the middle, with a few shallow, rounded or subacute teeth (7 or less on each side) --13.

13a. Large tree; leaves densely white-tomentose beneath; acorn on a stalk 3-10 cm. long =Swamp White Oak, Quercus bicolor.=

13b. Shrub; leaves thinly white-tomentose beneath; acorn sessile or nearly so =Scrub Oak, Quercus prinoides.=

URTICACEAE, the Nettle Family

Herbs or trees, with small inconspicuous apetalous flowers.

1a. Trees or tall shrubs --2.

1b. Herbs --7.

2a. Leaves oblong-ovate to lanceolate, serrate --3.

2b. Leaves broadly ovate to rotund, some of them lobed (Mulberry) --6.

3a. Leaves thick, coarsely and doubly serrate, broadest near the middle (Elm) --4.

3b. Leaves thin, simply serrate, broadest distinctly below the middle =Hackberry, Celtis occidentalis.=

4a. Some of the branches with flat corky wings; leaves smooth above =Cork Elm, Ulmus racemosa.=

4b. Branches without corky wings; leaves more or less rough above --5.

5a. Petioles and axillary buds glabrous =White Elm, Ulmus americana.=

5b. Petioles and axillary buds pubescent with rusty hairs =Slippery Elm, Ulmus fulva.=

6a. Leaves rough above =Red Mulberry, Morus rubra.=

6b. Leaves smooth above =White Mulberry, Morus alba.=

7a. Leaves alternate --8.

7b. Leaves opposite --9.

8a. Leaves 2-5 cm. long, stems pubescent =Pellitory, Parietaria pennsylvanica.=

8b. Leaves 8-20 cm. long; stem armed with stinging hairs =Wood Nettle, Laportea canadensis.=

9a. Twining plant; leaves serrate or cleft =Hop, Humulus lupulus.=

9b. Erect plant; leaves palmately compound =Hemp, Cannabis sativa.=

9c. Erect plants; leaves not lobed or compound --10.

10a. Stems armed with stinging hairs --11.

10b. Stems glabrous or rough, but not with stinging hairs --12.

11a. Leaves ovate, with a heart-shape base =Stinging Nettle, Urtica dioica.=

11b. Leaves lanceolate or ovate-lanceolate, not heart-shape at base =Slender Nettle, Urtica gracilis.=

12a. Stems glabrous, pellucid =Clearweed, Pilea pumila.=

12b. Stems rough, opaque =False Nettle, Boehmeria cylindrica.=

SANTALACEAE, the Sandalwood Family

Low herbs with alternate entire leaves and terminal clusters of small greenish-white bell-shape flowers without petals in spring and early summer.

1a. Inflorescence of several-flowered clusters terminating the stem and in the upper axils =Toad-flax, Comandra umbellata.=

1b. Inflorescence of axillary clusters of 1-5 flowers =Toad-flax, Comandra livida.=

LORANTHACEAE, the Mistletoe Family

Parasitic plants, attached to the branches of trees.

One species in Michigan, a dwarf brown plant 5-20 mm. long, with minute scale-like leaves, growing on the branches of Black Spruce =Dwarf Mistletoe, Arceuthobium pusillum.=

ARISTOLOCHIACEAE, the Birthwort Family

Flowers greenish-brown or reddish-brown, at or near the ground, with inferior 6-celled ovary.

1a. Leaves alternate, on the stem; flowers on a basal scaly branch (1-4 dm. high; summer) =Virginia Snakeroot, Aristolochia serpentaria.=

1b. Leaves a single basal pair, bearing 1 short-stalked flower between them (spring) (Wild Ginger) --2.

2a. Lobes of the perianth ending in a tubular portion 5-8 mm. long =Wild Ginger, Asarum canadense.=

2b. Lobes of the perianth ending in a tubular portion over 1 cm. long =Wild Ginger, Asarum canadense var. acuminatum.=

2c. Lobes of the perianth triangular, not tubular at the end =Wild Ginger, Asarum canadense var. reflexum.=

POLYGONACEAE, the Buckwheat Family

Herbs with alternate entire leaves, stipules surrounding the stem above the base of each leaf, and small green, white or pink flowers without petals.

1a. Erect or ascending or prostrate or floating plants --2.

1b. Scrambling or climbing plants, clinging by sharp recurved prickles on the 4-angled stems (flowers greenish or pink, summer) (Tear-thumb) --32.

1c. Twining vines (flowers white or greenish, summer) --33.

2a. Sepals 6, the 3 inner ones enlarging in fruit and surrounding the achenes; flowers in panicles --3.

2b. Sepals 4 or 5 (occasional flowers may be found with 6 sepals, but the flowers are not in panicles) (summer) --13.

3a. Leaves arrow-shape or halberd-shape, with 2 basal lobes (Sorrel) --4.

3b. Leaves without basal lobes (Dock) --5.

4a. Leaves halberd-shape, the basal lobes directed sidewise =Red Sorrel, Rumex acetosella.=

4b. Leaves arrow-shape, the basal lobes directed backward =Green Sorrel, Rumex acetosa.=

5a. The projecting wings of the fruiting calyx (known as valves) with sharp slender teeth =Bitter Dock, Rumex obtusifolius.=

5b. Valves entire or finely dentate, but without sharp slender teeth --6.

6a. Pedicels straight, thickened toward the end, all regularly deflexed, 3-4 times longer than the fruiting calyx =Swamp Dock, Rumex verticillatus.=

6b. Pedicels slender, flexuous, spreading --7.

7a. Leaves flat or nearly so --8.

7b. Leaves with strongly crisped or wavy-curled margins; plants usually of cultivated grounds or waste places (5-10 dm., summer) --12.

8a. With grain-like tubercles on all 3 valves of the fruit --9.

8b. With grain-like tubercles on only one valve, or entirely lacking --10.

9a. Valves broadly cordate, finely toothed =Water Dock, Rumex brittanica.=

9b. Valves triangular-ovate, entire or nearly so =Dock, Rumex mexicanus.=

10a. Valves oblong =Bloody Dock, Rumex sanguineus.=

10b. Valves broadly heart-shape --11.

11a. Grain-like tubercle less than half as long as the valve =Patience Dock, Rumex patientia.=

11b. Grain-like tubercle more than half as long as the valve =Tall Dock, Rumex altissimus.=

12a. The grain-like tubercle on the valves of the fruit broadly ellipsoid, with rounded apex =Sour Dock, Rumex crispus.=

12b. Tubercle ovoid with tapering apex =Sour Dock, Rumex elongatus.=

13a. Flowers inconspicuous, in small axillary clusters; leaves jointed at the base (Knotweed) --14.

13b. Flowers more or less conspicuous, in obvious spikes or racemes which terminate the stems or branches, or arise from the axils of the upper leaves --18.

14a. Leaves sharply folded lengthwise (1-4 dm. tall) =Knotweed, Polygonum tenue.=

14b. Leaves flat or nearly so --15.

15a. The small sepals pink or white at the margin (stems prostrate or ascending) --16.

15b. Sepals greenish or yellowish throughout (stems erect or ascending) --17.

16a. Leaves thin; common weed of dooryards and gardens =Knotweed, Polygonum aviculare.=

16b. Leaves thick and fleshy; a plant of sandy shores =Knotweed, Polygonum aviculare var. littorale.=

17a. Leaves narrowly lanceolate or linear-oblong; rare species =Knotweed, Polygonum ramosissimum.=

17b. Leaves broadly oblong, oval, or elliptical; common weed of yards and gardens =Knotweed, Polygonum erectum.=

18a. Leaves broadly triangular (3-7 dm. high; flowers white) =Buckwheat, Fagopyrum esculentum.=

18b. Leaves from linear to ovate or oblong --19.

19a. Sepals 4; flowers in very long and slender spike-like racemes (4-10 dm. high) =Knotweed, Polygonum virginianum.=

19b. Sepals 5; flowers in spikes or racemes --20.

20a. Flowers on slender pedicels, forming a loose raceme; leaves linear, jointed at the base (1-3 dm. high; flowers pink or white; chiefly near the Great Lakes) =Jointweed, Polygonella articulata.=

20b. Flowers sessile or nearly so, forming a spike or spike-like raceme --21.

21a. Stipular sheaths at the base of the leaves ciliate at their upper margin --22.

21b. Stipular sheaths not ciliate at the upper margin --28.

22a. Sheaths with spreading borders --23.

22b. Sheaths without a spreading border, appressed to the stem (Smartweed) --24.

23a. Leaves ovate, acuminate; stem erect (1-2 m. high; flowers pink) =Prince's Feather, Polygonum orientate.=

23b. Leaves oblong, obtuse or subacute; spreading or ascending plant of wet soil =Water Smartweed, Polygonum amphibium var. hartwrightii.=

24a. Peduncles with glandular hairs (5-15 dm. high) =Smartweed, Polygonum careyi.=

24b. Peduncles not glandular (1-8 dm. high) (Smartweed) --25.

25a. Sepals beset with minute black dots --26.

25b. Sepals white, pink, or red, not black-dotted --27.

26a. Racemes drooping or nodding at the tip; achene dull-colored =Smartweed, Polygonum hydropiper.=

26b. Racemes erect; achene smooth and shining =Smartweed, Polygonum acre.=

27a. Sheaths smooth; leaves usually with a dark spot near the base =Smartweed, Polygonum persicaria.=

27b. Sheaths hairy; leaves not dark-spotted =Smartweed, Polygonum hydropiperoides.=

28a. Leaves obtuse or somewhat acute at the apex --29.

28b. Leaves acuminate at the apex (5-15 dm. high; flowers white to pink) (Smartweed) --30.

29a. Stem unbranched, erect, bearing a single terminal raceme (5-30 cm. high; flowers pink) =Bistort, Polygonum viviparum.=

29b. Stem branched, submerged in water or creeping on muddy shores (flowers pink) =Water Smartweed, Polygonum amphibium.=

30a. Raceme single or two; leaves broadly ovate-lanceolate, about 3 times as long as wide =Smartweed, Polygonum muhlenbergii.=

30b. Racemes numerous; leaves lanceolate, 4-6 times as long as wide --31.

31a. Racemes drooping or nodding at the tip =Smartweed, Polygonum lapathifolium.=

31b. Racemes erect =Smartweed, Polygonum pennsylvanicum.=

32a. Leaves arrow-shape, the basal lobes pointing backward =Tear-thumb, Polygonum sagittatum.=

32b. Leaves halberd-shape, the basal lobes pointing sidewise =Tear-thumb, Polygonum arifolium.=

33a. The three outer sepals becoming conspicuously winged in fruit (False Buckwheat) --34.

33b. The sepals all unchanged in fruit, except in size (Black Bindweed) --35.

34a. Wings of the fruit with wavy-curled margins =False Buckwheat, Polygonum scandens.=

34b. Wings of the fruit flat =False Buckwheat, Polygonum dumetorum.=

35a. Leaf-sheaths with a ring of bristles at the base =Black Bindweed, Polygonum cilinode.=

35b. Leaf-sheaths without a ring of bristles =Black Bindweed, Polygonum convolvulus.=

CHENOPODIACEAE, the Goosefoot Family

Herbs, with inconspicuous greenish or reddish flowers without petals, in summer.

1a. Leaves linear or nearly so, entire --2.

1b. Leaves of a broader shape, usually toothed or lobed --5.

2a. Leaves rather stiff, narrowly linear or thread-like, with spine-like tips =Russian Thistle, Salsola kali var. tenuifolia.=

2b. Leaves soft, not spine-like --3.

3a. Widely branched, rather diffuse, 1-5 dm. tall; plant of the shore of the Great Lakes =Bug-seed, Corispermum hyssopifolium.=

3b. Erect plants with ascending branches --4.

4a. Leaves glabrous (3-6 dm. tall) =Goosefoot, Chenopodium leptophyllum.=

4b. Leaves minutely ciliate on the margin (bushy branched, 5-10 dm. tall) =Kochia, Kochia scoparia.=

5a. Principal leaves with a broad truncate, rounded, or hastate base --6.

5b. Principal leaves narrowed to the base --12.

6a. Leaves broadly ovate, with 1-4 large sharp projecting teeth on each side =Goosefoot, Chenopodium hybridum.=

6b. Leaves hastate or triangular-ovate, entire or with many teeth --7.

7a. Leaves entire or merely undulate --8.

7b. Leaves sharply or sinuately toothed --9.

8a. Stem erect, simple or sparingly branched =Good King Henry, Chenopodium bonus-henricus.=