22b. Leaves deeply pinnatifid --23.
23a. Pod dehiscent when ripe by two valves, tipped with a flat or angled
beak =White Mustard, Brassica alba.=
23b. Pod indehiscent, with spongy cross-partitions between the seeds,
tipped with a conical beak =Wild Radish, Raphanus raphanistrum.=
24a. Terminal segment of the principal leaves much larger than the
lateral segments; flowers in spring and summer --25.
24b. Terminal segment of the principal leaves equaling or smaller
than the lateral ones (5-10 dm. high; pods very long and
slender; flowers in summer)
=Sisymbrium, Sisymbrium altissimum.=
25a. Flowers about 3 mm. wide; pods erect and closely appressed to the
stem (3-9 dm. high; weed blooming in summer) (Hedge Mustard) --26.
25b. Flowers about 7 mm. wide; pods spreading or ascending (3-6 dm.
high; flowers in spring) (Winter Cress) --27.
26a. Pods pubescent =Hedge Mustard, Sisymbrium officinale.=
26b. Pods glabrous
=Hedge Mustard, Sisymbrium officinale var. leiocarpum.=
27a. Lateral leaf-segments 5-8 pairs on the principal leaves
=Winter Cress, Barbarea verna.=
27b. Lateral leaf-segments 1-4 pairs on the principal leaves --28.
28a. Flowers bright yellow, in racemes; pods spreading or ascending
=Winter Cress, Barbarea vulgaris.=
28b. Flowers pale yellow, in corymb-like clusters; pods erect and
somewhat appressed =Winter Cress, Barbarea stricta.=
29a. Principal stem-leaves compound or deeply lobed (the uppermost or
bracteal leaves may be simple) --30.
29b. Principal stem-leaves entire, dentate, serrate, or sometimes
shallowly lobed or none (the basal leaves, at the surface of the
ground, may be deeply lobed or compound) --42.
30a. Leaves ternately divided or compound (2-5 dm. high; flowers in
spring) (Toothwort) --31.
30b. Leaves pinnately divided or compound --33.
31a. Leaf-segments lanceolate or narrowly oblong
=Toothwort, Dentaria laciniata.=
31b. Leaf-segments ovate or ovate-oblong --32.
32a. Stem-leaves 2, opposite or nearly opposite
=Toothwort, Dentaria diphylla.=
32b. Stem-leaves 2-5, alternate
=Toothwort, Dentaria maxima.=
33a. Plants growing in water, or in mud near water (spring and summer)
--34.
33b. Plants of dry or moist soil --35.
34a. Aerial leaves distinctly compound, with 3-11 leaflets
=Water Cress, Radicula nasturtium-aquaticum.=
34b. Aerial leaves merely serrate to pinnatifid; the submerged
leaves, if present, dissected
=Lake Cress, Radicula aquatica.=
35a. Flowers 5 mm. broad, or less --36.
35b. Flowers 6 mm. broad, or more --39.
36a. Stem-leaves irregularly pinnatifid or lobed; pod about as
broad as long (2-4 dm. high; flowers in summer)
=Garden Cress, Lepidium sativum.=
36b. Stem-leaves distinctly pinnatifid, with 3-6 pairs of lateral
segments (spring) (Bitter Cress) --37.
37a. Leaves chiefly basal, pubescent on the upper side (1-3 dm. tall)
=Bitter Cress, Cardamine hirsuta.=
37b. Stem-leaves conspicuous, glabrous on the upper side --38.
38a. Plant of dry soil; flowers about 3 mm. wide (1-4 dm. high)
=Bitter Cress, Cardamine parviflora.=
38b. Plant of moist or wet soil; flowers about 5 mm. wide (2-8 dm.
high) =Bitter Cress, Cardamine pennsylvanica.=
39a. Leaves irregularly pinnatifid or lobed, not segmented into
definitely paired divisions (coarse plants 4-8 dm. high; flowers
in summer) --40.
39b. Leaves deeply segmented into 3-10 pairs of divisions --41.
40a. Flowers pink or white from the first
=Radish, Raphanus sativus.=
40b. Flowers yellow at first, turning white with age
=Wild Radish, Raphanus raphanistrum.=
41a. Flowers pink or white, appearing in spring (2-5 dm. high)
=Cuckoo Flower, Cardamine pratensis.=
41b. Flowers yellowish or cream-color; a weed blooming in summer (5-10
dm. high) =Sisymbrium, Sisymbrium altissimum.=
42a. A fleshy, much-branched plant of the shores of the Great
Lakes, with a pod transversely divided into two joints
(2-3 dm. high; summer) =Sea Rocket, Cakile edentula.=
42b. Pod not transversely divided into two joints --43.
43a. Pod short, its length not more than 3 times its diameter --44.
43b. Pod long and slender, its length more than 3 times its diameter
--55.
44a. Pods not conspicuously flattened, thick and plump, about
circular in cross-section (flowers in summer) --45.
44b. Pods distinctly flat --46.
45a. A plant escaped from cultivation in dry or moist soil, with very
large basal leaves (5-10 dm. high)
=Horse Radish, Radicula armoracia.=
45b. A plant of water or very wet soil, the largest leaves seldom more
than 15 cm. long (1-5 dm. tall) =Lake Cress, Radicula aquatica.=
46a. Stem-leaves clasping the stem by an auricled base --47.
46b. Stem-leaves sessile or petioled, not clasping, or none --49.
47a. Stem and leaves glabrous or pubescent; pod very flat and circular,
about 10 mm. wide (1-5 dm. tall; early summer)
=Penny Cress, Thlaspi arvense.=
47b. Stem and leaves glabrous or pubescent; pod not more than 5 mm. wide
(1-6 dm. high; spring and early summer) --48.
48a. Pods broadly ovate =Field Cress, Lepidium campestre.=
48b. Pods triangular, or slightly indented at the apex
=Shepherd's Purse, Capsella bursa-pastoris.=
49a. Pods about circular, or a very little longer than broad --50.
49b. Pods ovoid or oblong, broadest near the middle, and distinctly
longer than wide (Whitlow Grass) --53.
50a. Leaves entire (1-3 dm. high; flowers in summer)
=Yellow Alyssum, Alyssum alyssoides.=
50b. Leaves serrate (2-6 dm. high; flowers in summer) --51.
51a. Stamens 6 =Garden Cress, Lepidium sativum.=
51b. Stamens 2 (Pepper Grass) --52.
52a. Petals present =Pepper Grass, Lepidium virginicum.=
52b. Petals none =Pepper Grass, Lepidium apetalum.=
53a. Petals deeply 2-cleft (about 1 dm. high; early spring)
=Whitlow Grass, Draba verna.=
53b. Petals entire or barely notched at the tip --54.
54a. Leaves all or chiefly at or near the base (about 1 dm. high;
spring) =Whitlow Grass, Draba caroliniana.=
54b. Stems leafy up to the flowers (1-5 dm. high; summer)
=Whitlow Grass, Draba arabisans.=
55a. Stem-leaves cordate or sagittate at the base and sessile, forming a
more or less clasping leaf (3-10 dm. high) (Rock Cress) --56.
55b. Stem-leaves sessile or somewhat petioled, but not clasping --63.
56a. Seeds in 2 rows in each cavity of the pod (early summer) --57.
56b. Seeds in 1 row in each cavity of the pod --59.
57a. Calyx pubescent; the pods reflexed =Rock Cress, Arabis holboellii.=
57b. Calyx glabrous; the pods spreading or ascending --58.
58a. Basal leaves densely pubescent
=Rock Cress, Arabis brachycarpa.=
58b. Basal leaves smooth or nearly so
=Rock Cress, Arabis drummondii.=
59a. Petals conspicuous, about twice as long as the calyx, or longer;
straight, erect, mostly unbranched plants --60.
59b. Petals inconspicuous, equaling or but little longer than the calyx
--61.
60a. Pods 3-4 cm. long, ascending (summer)
=Rock Cress, Arabis patens.=
60b. Pods 8-10 cm. long, recurved (late spring)
=Rock Cress, Arabis laevigata.=
61a. Pods widely spreading; stem usually sparingly branched near the
base (spring) =Rock Cress, Arabis dentata.=
61b. Pods erect or appressed; stem usually unbranched (summer) --62.
62a. Stem-leaves and stem smooth and glaucous
=Rock Cress, Arabis glabra.=
62b. Stem-leaves and stem almost always pubescent, and never
glaucous =Rock Cress, Arabis hirsuta.=
63a. Principal stem-leaves 7-10 cm. long, or more --64.
63b. Principal stem-leaves 2-5 cm. long --65.
64a. Leaves lanceolate or oblong; flowers 10 mm. wide or less (3-7
dm. high; summer) =Rock Cress, Arabis canadensis.=
64b. Leaves ovate or ovate-lanceolate; flowers 15-20 mm. wide (5-8
dm. high; late spring and summer)
=Dame's Rocket, Hesperis matronalis.=
65a. Basal leaves ovate to orbicular or cordate, not more than twice as
long as broad (1-3 dm. high; spring) (Bitter Cress) --66.
65b. Basal leaves oblong, lanceolate, or oblanceolate, at least 3 times
as long as broad (1-3 dm. high) --67.
66a. Flowers purple or rose color
=Bitter Cress, Cardamine douglassii.=
66b. Flowers white =Bitter Cress, Cardamine bulbosa.=
67a. Basal leaves pinnatifid (spring and summer)
=Rock Cress, Arabis lyrata.=
67b. Basal leaves entire or toothed --68.
68a. Leaves narrowly oblanceolate; rare plant occurring from
Mackinac northward (summer) =Rock Cress, Braya humilis.=
68b. Leaves obovate or oblong; an introduced weed (spring)
=Mouse-ear Cress, Sisymbrium thalianum.=
CAPPARIDACEAE, the Caper Family
Herbs, with alternate compound leaves, 4 petals, and 6 or more stamens,
which are about equal in length; fruit a 1-celled pod.
One species in Michigan, stamens about 11; leaflets 3 (2-4 dm. high;
flowers yellowish, in summer) =Clammy-weed, Polanisia graveolens.=
RESEDACEAE, the Mignonette Family
Herbs, with alternate leaves and terminal racemes of small yellowish
flowers; sepals 6, petals 6, stamens numerous.
One species in Michigan, with divided leaves and irregularly cleft
petals, blooming in summer =Yellow Mignonette, Reseda lutea.=
SARRACENIACEAE, the Pitcher Plant Family
Insectivorous plants, with hollow, pitcher-shaped leaves, and large
purple flowers at the ends of naked stems.
One species in Michigan, growing in bogs and blooming in late spring
=Pitcher Plant, Sarracenia purpurea.=
DROSERACEAE, the Sundew Family
Insectivorous herbs, with a rosette of basal leaves bearing gland-tipped
bristles on their upper surface, and with slender racemes of small white
flowers in summer; inhabitants of bogs and swamps (2 dm. high, or less).
1a. Leaf-blade about as long as wide =Sundew, Drosera rotundifolia.=
1b. Leaf-blade about 2-3 times as long as wide
=Sundew, Drosera longifolia.=
1c. Leaf-blade about 5-8 times as long as wide
=Sundew, Drosera anglica.=
1d. Leaf-blade narrowly linear, about 10 times as long as wide
=Sundew, Drosera linearis.=
PODOSTEMACEAE, the River Weed Family
Small submerged aquatics, growing attached to stones in running water,
with dissected leaves and minute flowers.
One species in Michigan =River Weed, Podostemum ceratophyllum.=
CRASSULACEAE, the Orpine Family
Herbs, with usually alternate leaves; the sepals, petals, and pistils
each 4 or 5, or in one species the petals none, and the stamens as many
or twice as many as the sepals.
1a. Leaves entire (Stonecrop) --2.
1b. Leaves toothed --3.
2a. Leaves 3-5 mm. long, very thick and fleshy (tufted plants about
1 dm. high, with yellow flowers in summer)
=Stonecrop, Sedum acre.=
2b. Leaves 10-30 mm. long, flat (tufted plants 1-2 dm. high;
flowers white, in spring) =Stonecrop, Sedum ternatum.=
3a. Petals present, purple (2-5 dm. high; summer)
=Live-for-ever, Sedum purpureum.=
3b. Petals none (3-6 dm. high; summer)
=Ditch Stonecrop, Penthorum sedoides.=
SAXIFRAGACEAE, the Saxifrage Family
Herbs or shrubs, with alternate or opposite leaves; petals and sepals
each 5, or the petals none; stamens 5 or 10; styles or stigmas 2-4.
1a. Shrubs with lobed leaves (3-15 dm. high; flowers in late spring)
--2.
1b. Herbs --12.
2a. Stems thorny --3.
2b. Stems not thorny (Currant) --8.
3a. Flowers and fruits in racemes =Swamp Currant, Ribes lacustre.=
3b. Flowers and fruit in short clusters (Gooseberry) --4.
4a. Ovary and fruit prickly and bristly
=Gooseberry, Ribes cynosbati.=
4b. Ovary and fruit smooth, or sometimes a little glandular --5.
5a. Stamens equaling the ovate calyx-lobes in length, or a very little
longer --6.
5b. Stamens distinctly longer than the linear calyx-lobes --7.
6a. Leaves glabrous beneath, or nearly so
=Gooseberry, Ribes oxyacanthoides.=
6b. Leaves softly pubescent beneath
=Gooseberry, Ribes oxyacanthoides var. calcicola.=
7a. Flowers, including the stamens, about 15 mm. long
=Gooseberry, Ribes gracile.=
7b. Flowers, including the stamens, about 8 mm. long
=Gooseberry, Ribes rotundifolium.=
8a. Calyx prolonged above the ovary into a tube which is longer
than the sepals --9.
8b. Calyx-tube shorter than the ovary or none --10.
9a. Flowers greenish-yellow, inconspicuous; calyx-tube narrowly
bell-shape =Black Currant, Ribes floridum.=
9b. Flowers bright yellow, conspicuous; calyx-tube narrow, with
spreading lobes =Golden Currant, Ribes aureum.=
10a. Ovary and berry bristly with glandular hairs
=Skunk Currant, Ribes prostratum.=
10b. Ovary and fruit smooth, or with sessile glands --11.
11a. Leaves dotted beneath with resinous glands
=Black Currant, Ribes hudsonianum.=
11b. Leaves glabrous or pubescent beneath, without resinous glands
=Red Currant, Ribes triste.=
12a. Flowers minute, yellowish, without petals, in the axils of the
leaves (1-2 dm. high; flowers in spring)
=Golden Saxifrage, Chrysosplenium americanum.=
12b. Flowers large, solitary, terminating erect stalks (leaves
mostly basal; flowers white, in late summer; flower-stalks
1-5 dm. high) (Grass-of-Parnassus) --13.
12c. Flowers in terminal racemes, panicles, or clusters --15.
13a. Flowers less than 2 cm. wide; leaves narrowed to the base
=Grass-of-Parnassus, Parnassia parviflora.=
13b. Flowers 2-3.5 cm. wide; leaves rounded or cordate at the base --14.
14a. A 3-cleft scale at the base of each petal
=Grass-of-Parnassus, Parnassia caroliniana.=
14b. A many-cleft (9-15) scale at the base of each petal
=Grass-of-Parnassus, Parnassia palustris.=
15a. Leaves linear to oblanceolate, 3 times as long as broad, or more,
and pinnately veined (Saxifrage) --16.
15b. Leaves broadly ovate to nearly circular, frequently cordate at the
base, and always palmately veined or lobed --20.
16a. Leaves basal; the flower-stalk bearing no leaves except small
ones at the base of its branches --17.
16b. Flower-stalk leafy below (1-3 dm. high; flowers yellow,
summer) --18.
17a. Petals white; sepals erect; leaves conspicuously toothed, 3-10 cm.
long (1-3 dm. high; spring) =Saxifrage, Saxifraga virginiensis.=
17b. Petals greenish; sepals reflexed; leaves minutely toothed or
entire, 10-30 cm. long (5-10 dm. high; spring)
=Saxifrage, Saxifraga pennsylvanica.=
18a. Leaves with 3 sharp teeth at the apex
=Saxifrage, Saxifraga tricuspidata.=
18b. Leaves with numerous teeth or entire --19.
19a. Leaves linear, chiefly on the stem
=Saxifrage, Saxifraga aizoides.=
19b. Leaves spatulate, chiefly in a basal rosette
=Saxifrage, Saxifraga aizoon.=
20a. Stamens 5 (leaves mostly basal; flowers greenish or purplish
in late spring, on stalks 5-10 dm. high) (Alum Root) --21.
20b. Stamens 10 (flowers white, in spring) --23.
21a. Flowers regular =Alum Root, Heuchera americana.=
21b. Flowers irregular, the calyx oblique, longer on the upper side than
on the lower --22.
22a. Stamens projecting beyond the calyx
=Alum Root, Heuchera hirsuticaulis.=
22b. Stamens not projecting beyond the calyx
=Alum Root, Heuchera hispida.=
23a. Stem-leaves alternate or none --24.
23b. Stem with a pair of opposite leaves (2-4 dm. high)
=Bishop's Cap, Mitella diphylla.=
24a. Petals deeply fringed (1-2 dm. high)
=Bishop's Cap, Mitella nuda.=
24b. Petals entire (1-3 dm. high)
=False Mitrewort, Tiarella cordifolia.=
HAMAMELIDACEAE, the Witch Hazel Family
Shrubs, with alternate simple leaves; sepals, petals, and stamens each
4; ovary 2-lobed.
One species in Michigan; tall shrub with obovate leaves and yellow
flowers appearing late in autumn =Witch Hazel, Hamamelis virginiana.=
PLATANACEAE, the Plane Tree Family
Trees, with broad, palmately veined and lobed leaves, and minute flowers
in dense spherical heads.
One species in Michigan =Sycamore, Platanus occidentalis.=
ROSACEAE, the Rose Family
Trees, herbs, or shrubs, with alternate, frequently compound leaves;
petals and sepals usually 5, stamens numerous, pistils 1 to many;
receptacle expanded into a saucer-shape or cup-shape organ, bearing the
sepals, petals, and stamens at its margin, the pistils at its center,
and resembling a calyx-tube or flattened calyx.
1a. Shrubs or trees --2.
1b. Herbaceous plants --48.
2a. Leaves compound --3.
2b. Leaves simple --24.
3a. Flowers in large panicles or corymbs, each flower 5-10 mm. across;
leaflets 7 or more --4.
3b. Flowers solitary or in small clusters, each flower usually 20-80 mm.
wide; leaflets frequently only 3 or 5 --7.
4a. Flowers in a pyramidal or oblong panicle, the ovaries superior
(1-2 m. high; flowers white, in summer) --70b.
4b. Flowers in rounded or hemispheric clusters, the ovary inferior
--5.
5a. Leaves pubescent on the lower surface
=Rowan Tree, Pyrus aucuparia.=
5b. Leaves glabrous beneath when mature (small trees; flowers white, in
early summer or late spring) (Mountain Ash) --6.
6a. Leaves acuminate at the apex =Mountain Ash, Pyrus americana.=
6b. Leaves obtuse or acute at the apex
=Mountain Ash, Pyrus sitchensis.=
7a. Flowers yellow (5-10 dm. high; summer)
=Cinquefoil, Potentilla fruticosa.=
7b. Flowers pink or red, rarely white, 4-10 cm. across (shrubs, 5-15 dm.
high, or climbing; stems usually thorny; flowers in early summer)
(Rose) --8.
7c. Flowers white, 1-3 cm. across (4-20 dm. high; flowers in late
spring) --16.
8a. Leaflets on most of the leaves 3; styles cohering in a column
which protrudes from among the stamens
=Climbing Rose, Rosa setigera.=
8b. Leaflets 5-11; styles not cohering in a protruding column --9.
9a. Sepals persistent on the fruit after flowering --10.
9b. Sepals soon deciduous from the young fruit after flowering --14.
10a. A pair of spines below each leaf larger than the other spines
--11.
10b. Spines all alike in size or nearly so, or absent completely
--12.
11a. Sepals entire =Wild Rose, Rosa woodsii.=
11b. Sepals pinnatifid =Dog Rose, Rosa canina.=
12a. Stems with few thorns or none at all =Wild Rose, Rosa blanda.=
12b. Stems prickly --13.
13a. Fruit somewhat pear-shape, narrowed toward the base.
=Wild Rose, Rosa acicularis.=
13b. Fruit globose, rounded at the base
=Wild Rose, Rosa acicularis var. bourgeauiana.=
14a. The pair of spines at the base of each leaf straight or nearly
so =Wild Rose, Rosa humilis.=
14b. The pair of spines at the base of each leaf distinctly
recurved or hooked --15.
15a. Leaves densely glandular-pubescent beneath
=Sweetbrier, Rosa rubiginosa.=
15b. Leaves glabrous or minutely pubescent =Swamp Rose, Rosa carolina.=
16a. Stems trailing or creeping --17.
16b. Stems erect, ascending, or arched --19.
17a. Stems distinctly shrubby and thorny (Dewberry) --18.
17b. Stems almost herbaceous, without thorns
=Dwarf Raspberry, Rubus triflorus.=
18a. Leaves thin, dull above; fruit black, large and juicy
=Dewberry, Rubus villosus.=
18b. Leaves firm or thick, shining above; fruit reddish, small,
consisting of a few sour drupelets
=Swamp Dewberry, Rubus hispidus.=
19a. Ripe fruit dropping away from the white receptacle or core;
terminal leaflet of each leaf with a long stalk, while the lateral
leaflets are sessile or nearly so (Raspberry) --20.
19b. Ripe fruit and receptacle or core dropping together; all the
leaflets on stalks which are approximately equal in length
(Blackberry) --22.
20a. Stem very glaucous with a whitish or bluish waxy deposit;
fruit black =Black Raspberry, Rubus occidentalis.=
20b. Stem not glaucous; fruit red --21.
21a. Calyx velvety-pubescent =Red Raspberry, Rubus idaeus.=
21b. Calyx bristly-hispid
=Red Raspberry, Rubus idaeus var. aculeatissimus.=
22a. Pedicels with gland-tipped hairs, but no prickles
=Blackberry, Rubus allegheniensis.=
22b. Pedicels with prickles =Blackberry, Rubus nigricans.=
22c. Pedicels with neither prickles nor gland-tipped hairs --23.
23a. Leaves downy beneath =Blackberry, Rubus frondosus.=
23b. Leaves smooth beneath =Blackberry, Rubus canadensis.=
24a. Ovaries 1 or more, superior (attached to the surface of the
receptacle, but not concealed within it or united to it) --25.
24b. Ovary 1, inferior (permanently enclosed within the receptacle,
with only the styles protruding) --38.
25a. Ovaries more than 1 --26.
25b. Ovary 1 --30.
26a. Leaves serrate --27.
26b. Leaves lobed --28.
27a. Leaves glabrous or very nearly so (8-20 dm. high; flowers white or
pinkish, summer) =Meadow-sweet, Spiraea salicifolia.=
27b. Leaves closely pubescent beneath (5-15 dm. high; flowers pink,
summer) =Hardhack, Spiraea tomentosa.=
28a. Flowers showy, purple or white, 3-4 cm. broad --29.
28b. Flowers white, about 1 cm. wide (1-3 m. high; flowers in early
summer) =Ninebark, Physocarpus opulifolius.=
29a. Flowers purple =Flowering Raspberry, Rubus odoratus.=
29b. Flowers white =Salmonberry, Rubus parviflorus.=
30a. Flowers in racemes (trees or tall shrubs; flowers white, in
late spring) --31.
30b. Flowers in small umbels or corymbs (flowers white, in spring)
--32.
31a. Leaves oblong, the points of their teeth incurved
=Black Cherry, Prunus serotina.=
31b. Leaves obovate, the points of their teeth spreading
=Choke Cherry, Prunus virginiana.=
32a. Flowers about 1 cm. wide --33.
32b. Flowers about 1.5-2.5 cm. wide --36.
33a. Low shrubs, with the spatulate or oblong leaves widest above the
middle --34.
33b. Erect tall shrubs or small trees, with the leaves widest below the
middle --35.
34a. An erect shrub (5-10 dm. high)
=Appalachian Cherry, Prunus cuneata.=
34b. A prostrate or ascending shrub (3-15 dm. high)
=Sand Cherry, Prunus pumila.=
35a. Leaves very broadly ovate, almost as wide as long (small tree)
=Perfumed Cherry, Prunus mahaleb.=
35b. Leaves oblong-lanceolate, about 3 times as long as broad (shrub or
small tree, 2-10 m. high) =Pin Cherry, Prunus pennsylvanica.=
36a. Sepals glandular-serrate (tall shrub or small tree)
=Wild Plum, Prunus nigra.=
36b. Sepals entire --37.
37a. Leaves with sharp teeth, frequently bristle-tipped; a native
species (tall shrub or small tree, frequently growing in thickets)
=Wild Plum, Prunus americana.=
37b. Leaves with obtuse teeth; a species escaped from cultivation
(widely branched tree) =Cherry, Prunus cerasus.=
38a. Trees, in cultivation or escaped from cultivation near roads
or dwellings, with showy flowers 2.5-5 cm. across, edible
fruits, and no thorns (spring) --39.
38b. Native species, trees or shrubs, growing in woods, fields, or
thickets; frequently with thorns (spring) --40.
39a. Leaves finely serrulate or entire =Pear, Pyrus communis.=
39b. Leaves coarsely serrate or somewhat lobed =Apple, Pyrus malus.=
40a. Shrubs or small trees, without thorns --42.
40b. Bushy trees or shrubs, with thorns or stiff thorn-like
branches, and with flowers generally 1.5-2.5 cm. across --41.
41a. Flowers pink, very fragrant =Wild Crab, Pyrus coronaria.=
41b. Flowers white (Hawthorn, the genus Crataegus). Several species of
this genus occur in the state, for the identification of which the
Manual must be used.
42a. Mid-vein glandular above (shrubs 1-3 m. tall; flowers white or
pink) (Chokeberry) --43.
42b. Mid-vein not glandular (shrubs or trees, 1-10 m. tall; flowers
white) (Juneberry) --44.
43a. Leaves glabrous beneath =Chokeberry, Pyrus melanocarpa.=
43b. Leaves tomentose beneath
=Chokeberry, Pyrus arbutifolia var. atropurpurea.=
44a. Petals 15-25 mm. long --45.
44b. Petals 5-12 mm. long --46.
45a. Mature leaves glabrous =Juneberry, Amelanchier canadensis.=
45b. Mature leaves pubescent beneath
=Juneberry, Amelanchier canadensis var. botryapium.=
46a. Flowers in racemes --47.
46b. Flowers solitary, or in small clusters of 2-4
=Juneberry, Amelanchier oligocarpa.=
47a. Leaves coarsely dentate, with about 1 tooth for each lateral vein
=Juneberry, Amelanchier spicata.=
47b. Leaves finely serrate, with about 2-3 teeth for each lateral vein
=Juneberry, Amelanchier oblongifolia.=
48a. Flowers yellow --49.
48b. Flowers white, pink, purple, or rose, never yellow --63.
49a. Plant with basal trifoliate leaves, resembling strawberry (1-3 dm.
high; late spring) =Barren Strawberry, Waldsteinia fragarioides.=
49b. Plants with leafy stems --50.