Week 17 Monday. Lecture: Sapindaceae s.l. (incl. Aceraceae and Hippocastanaceae)

Transcription

1 Week 17 Monday Lecture: Sapindaceae s.l. (incl. Aceraceae and Hippocastanaceae) The Aceraceae now is included in a larger family, the Sapindaceae, which is a paraphyletic ancestral group. The Sapindaceae largely is tropical and has more variation in floral morphology. This expanded family also includes the Hippocastanaceae, the Horse Chestnut or Buckeye family. The Aceraceae and Hippocastanaceae both are monophyletic, but by recognizing those families as distinct from the traditional Sapindaceae, the Sapindaceae would be paraphyletic. So, the most workable solution is to include them all in one family, Sapindaceae. The name Sapindaceae is used for the larger group, because it was used as a family name before either of the others. OVERHEAD Phylogenetic nomenclature because of the ranks (e.g., Order, Family, Genus, etc.) imposed by the Linnaean system and the rules of the International Code of Botanical Nomenclature, you can t have a family nested within another family, or a family in a genus, etc (against the rules). However, a consensus has emerged that we want groups (no matter what rank) to be monophyletic (i.e., natural groups). Therefore, there has been a lot of lumping and splitting of traditional groups etc. Sapindaceae s.l. is a good example. However, in some of these cases the lumped groups form good clades within that are easy to recognize and have long standing names that are well-known in the botanical community, why not continue to recognize them? The International code of Phylogenetic Nomenclature is a system that is rank-free and does just that. So in that system we could have the Sapindaceae clade and the Aceraceae and the Hippocastanaceae all clades that are easily defined and easily recognized. Therefore I want you to recognize that these groups are now treated in the broadly circumscribed Sapindaceae, but we will recognize the narrow definition of the two clades Aceraceae and Hippocastanaceae, because of their broad use. 116

2 Aceraceae - the maple clade (Sapindaceae s.l.) 2 genera Dipteronia (2 species native to central China) and Acer, which includes 110 species of trees and shrubs widely distributed throughout the Northern Hemisphere, but most prolific in central China and the eastern Himalayas with 14 species native to N. America. 1) trees or shrubs 2) leaves opposite MAD Cap Horse --> Maple, Ash, Dogwood, Caprifoliaceae, Horse chestnut. - typically palmate venation; usually simple, sometimes compound 3) Flowers: parted - nectary disk - formed in staminal whorls - flowers bisexual or unisexual, if the latter, then plants either mono- or dioecious, or androdioecious (some plants with perfect flowers, some plants with male flowers only; example Mountain maple A. glabrum) - may be insect or wind pollinated - fruit of 2 fused carpels each with pronounced wing and dispersed by wind samaroid schizocarp Hippocastanaceae - the buckeye clade (Sapindaceae s.l.) Includes 2 genera and ca. 25 species of trees and shrubs primarily in the Americas, southeastern Europe, eastern Asia and India, with 7 species native to N. America. As a group they are not important timber producers but are very important ornamentals. Aesculus horsechestnut The genus includes ca. 20 species of trees and large shrubs widely distributed in the northern Hemisphere. 7 species are native to N. America and are called buckeyes. European species are called horsechestnuts. 117

3 Acer - the maples They are important components of many forest communities and are highly valued for wood products & syrup and several species are important ornamentals. Acer silver maple Occupies moist sites, especially bottomlands throughout much of the eastern US. Occurs in association with several other river-bottomland species, Salix, Populus, Ulmus, Acer rubrum, uncommon on dry sites. It is fairly shade tolerant. Grows rapidly, may reach 60-80' tall and 2-3' diameter at maturity. An important timber tree, the source of "soft maple" used to make pallets & crates and for pulp. A very commonly planted ornamental that has escaped cultivation in many areas. Leaves are 4-6" long, simple, opposite, deciduous, deeply, palmately 5-lobed light green above and silvery below. Yellow to orange in the fall. Often distinctive vase-shape forking/y-shaped trunk. Shallow wide-spreading root system. Bark is smooth and gray on young trees but develops distinctive loosely attached scales on older trees. Polygamous (mixture of perfect and imperfect flowers) with reduced perianth, emerging very early in the spring before the leaves. Mericarp wingss widely divergent, wings 1 1/2-2 1/2" long. Matures early enough to take advantage of seasonally wet soils on the flood plain. Germinate the same season. Acer rubrum red maple Occupies variable sites from swampy bottomlands and moist alluvial soils to occasionally on rocky upland sites throughout much of eastern US. Most commonly associated with redmaple swamps. Formerly a minor component of many forest community types but due to fire suppression and anthropogenic disturbances it has become a major component of many forest community types. Capable of pioneering diverse sites and is moderately shade tolerant. Red flowers & fruit and fall colors in combination with ability to grow well on diverse sites have led to widespread use as an ornamental. Many cultivars exist. Wood is similar to silver maple, "soft" and used for the same purposes. May reach 50-70' tall and 1-2' diameter at maturity. 118

4 Leaves are 2 1/2-4" long, simple, opposite, deciduous, palmately 3-5-lobed with serrate margins. Sinuses at right angles. Light green above, pale and glaucous below. Leaves are similar to Acer glabrum. Fall color is red! Shallow wide-spreading root system. Bark is smooth and gray on young trees but breaks into scaly plates on older trees. Flowers are polygamous with reduced perianth, emerging very early in the spring before the leaves. Mericarp wings slightly divergent approximately 3/4" long. Fruit matures in late spring, sheds and seeds germinate in days, in time to take advantage of seasonally wet soils much like silver maple. Acer saccharum sugar maple Occupies mesic sites of the northern and central deciduous zones, ie. east of the Mississippi except southern states. Extremely shade tolerant. Frequent associates include Betula alleghaniensis and Fagus grandifolia to form the climax community in the northern deciduous zone. Beech-maple in the central deciduous zone. Has 3-5-lobed leaves with acute to rounded apex and pubescence in the Southern portion of its range. Often designated as var. floridanum. Taxonomic disagreements. Has 3-lobed pubescent leaves with stipules in the northern portion of its range. Often designated as Acer nigrum but considerable bickering over taxonomic placement occurs. Has been in decline in the NE due possibly to acid rain and pathogens. A very important timber tree. The source of "hard" or "rock" maple used to make furniture, cabinetry and flooring. The commercial source for maple syrup and sugar. Average mature tree will produce about 16 gallons of 1-2% sugar sap which when boiled down will make about 1/2 gallon of syrup. Also very important as an ornamental. May reach 60-80' tall and 2' diameter at maturity. Leaves are simple, opposite, deciduous, 3 1/2-5 1/2" long, palmately 5-lobed, margin entire or nearly so. Sinuses acute angles and rounded. Apex acuminate, base cordate, bright green above and pale below with both surfaces glabrous. Base of petiole is red in the spring. Red and yellow fall colors. Long clear trunk under forested conditions but branches near the ground when opengrown. Bark is gray and deeply furrowed on older trees. Flowers are polygamous, yellow, long pubescent pedicels, emerge with the leaves. Mericarp wings 1-1 1/4" long and parallel to slightly divergent. Mature in the fall. Sprouts from stumps and roots. 119

5 Acer negundo box-elder Most common on moist bottomlands but also found on drier & poorer soils than any other maple. Widely distributed in N. America includes most of the lower 48 (except the NW) and Alberta, Saskatchewan and Manitoba. Grows quickly and may reach 30-60' tall and 2-3 1/2" diameter at maturity. Can invade poorer and drier soils than other maples weedy. Leaves are pinnately (or palmately) compound, opposite and deciduous. 3-7 leaflets are short-petioled and variably toothed or lobed. The exception to the rule. Has a ragged form with weak, easily damaged limbs. Damaged by numerous pathogens. Dioecious, flowers are apetalous and yellow-green. Emerge with or before the leaves. Acer macropyhllum bigleaf maple Occupies riparian and alluvial terraces in association with Populus trichocarpa, Alnus spp. and several conifers on the Pacific slope from British Columbia to Southern California. Becoming important commercially. Wood is used for veneer, paneling, furniture, pianos, woodenware and fuel. May reach 50-80' tall and 3-4' diameter at maturity. Leaves are simple, opposite, deciduous, 6-10" long, palmately 5-lobed, bright green above paler below. Petioles have milky sap. Usually has a narrow crown and a long clear bole in forests but branches near the ground with wide round top when open grown. Bark is light gray-brown and smooth on younger trees but becomes furrowed on older trees. Polygamous, flowers are yellow-green, showy with perianth, borne in puberulent racemes. Mericarp wings are 1-1 1/2" long and densely pubescent. 120

6 Acer glabrum Rocky Mountain maple Occupies variable sites from riparian zone in drier habitats to the understory of mid-elevation conifer forests of the Cascades, Sierras and Rocky mountains. Can aggressively establish itself on disturbed sites and clearcuts with adequate moisture, (grand fir series through western red-cedar/western hemlock series). Large multi-trunked shrub or small tree may reach 30' tall and 1' diameter at maturity. Leaves are variable, usually 3-5-lobed in the Sierras, Cascades and northern Rockies but often pinnately compound with 3 leaflets in the S. Rockies. Bright green above, whitish below. Yellow fall color. Usually many-trunked with smooth gray bark. Conspicuous red twigs. Polygamous, small yellow flowers with 4 sepals and 4 petals that emerge with leaves. Mericarp wings moderately divergent, 3/4-1" long. Acer platanoides Norway maple Native to the forests of northern Euraisa, but has been widely introduced to many temperate regions of the world. Naturalized all over N. America. A very popular ornamental, tolerates urban conditions May reach 40-60' tall and 2' diameter at maturity. Leaves are simple, opposite, deciduous, 4-7" long, 5-lobed with acuminate apex with a very pinched sharp tip. Acute angled and rounded sinuses (similar to Acer sccharum. Light green above and paler below. Bark is dark gray-brown and tightly furrowed into narrow ridges on mature trees. Trunk is usually divided into several stout branches within ten feet of the ground resulting in a wide round top. Usually dioecious, yellowish green flowers emerge before the leaves. Mericarps widely divergent, 1 1/2-2" long. OTHER IMPORTANT IN PNW: (Acer circinatum vine maple) Occupies riparian zones in the Pacific slope from British Columbia to northern California. It most commonly grows as a large, multi-stemmed shrub growing to around ft tall, but it will occasionally form a small to medium-sized tree up to ~ 40 ft. 121

7 Leaves simple, opposite, deciduous, 7-9 lobed, lobes shallow, more or less equal length (fan-shaped) usually 3-5-lobed. Green above, pale green below. Yellow to orange-red fall color. Usually many-trunked with smooth greenish bark. Polygamous, small red flowers. Arranged in open corymbs. Mericarp wings widely divergent (180 degrees), 3/4-1" long, often red at maturity. Hippocastanaceae - the buckeye clade (Sapindaceae s.l.) Aesculus hippocastanum horsechestnut Native to the Balkan Peninsula but has been widely planted as an ornamental. It was introduced to the Americas in the late 16th century. Leaves are palmately compound, opposite and deciduous with 7 obovate (occasionally 5) leaflets. Big fat twigs & buds with sticky resins. Bark is gray-brown and loosely scaled on mature trees. Flowers showy and perfect, white with pink or yellow blotches on petals. Arranged in erect panicles. Fruit is a large leathery and moderately spiny capsule that contains a single hard brown, smooth seed. Seed contains is poisonous. 122

8 Week 17 Friday NOTE: not all of this material covered, but wanted you to have access to it. Simaroubaceae the bitterwood family Includes ca. 12 genera and 110 species of primarily tropical and subtropical trees with 4 species native to N. America and 1 introduced that has escaped. The family is known for having very bitter bark synapomorphy of having special triterpenoid secondary compounds that produce bitter taste. The wood of Quassia amara contains a compound used in the production of medicines and pesticides. Ailanthus altissima - tree-of-heaven Native to East Asia, but has been widely introduced and has escaped over much of N. America. Capable of growing on the poorest soils and tolerating extreme pollution. Very weedy and aggressive. Common on abandoned disturbed sites and waste places but also a serious problem in some hardwood forests. Ironically the tree-of-heaven will grow on the worst of all sites and has a nasty foul odor. Has been used to pioneer badly degraded sites superfund sites May reach 50-80' tall and 1-2' diameter at maturity. Leaves are 1-2' long, pinnately compound with ca ovate-lanceolate leaflets. Alternate and deciduous. Leaflets are 3-5" long with 1-5 basal teeth that have a black gland below. Foul smelling Twigs are large and pithy, very weak with large leaf scars. Also sprouts from roots and stumps. Stump sprouts may grow an inch a day. Bark is gray-brown and smooth on young trees but becomes fissured on older trees. Dioecous flowers small and yellowish in terminal clusters. Fruits are noticeably twisted samaras with the seed in the middle - borne in terminal clusters and often remaining on the tree over winter. Altingiaceae sweet gum family 1-3 genera and 12 spp. depending on classification. Traditionally placed in Hamamelidaceae (witch-hazel family), but do not form a mononphyletic group, so segregated. Only one species native to New World - Liquidambar styraciflua sweetgum, native to the southeastern US closest relative in western Asia (L. orientalis) same disjunction again tall commonly planted ornamental for foliage and fruits. Leaves palmately lobed, palmately veined star-shaped, margins finely serrate Flws. imperfect (plant monoecious) small flowers both in heads Fruit a woody, 2-celled, beaked capsule arranged in globose heads Twig often with corky wings. 123

9 Lecture: Urticales (elms, mulberrys) Ulmaceae the elm family Traditionally included approximately 18 genera and 150 species of shrubs and trees primarily in temperate regions of both hemispheres with a few in the tropics. However, now split between 2 families Ulmaceae (6 genera/40 species mostly in the northern Hemisphere temperate regions) and Cannabaceae (11 genera/180 species include both temperate and tropical members). Sytsma et al (overhead). Ulmaceae s.s. Most have simple, alternate, deciduous leaves with bases that are oblique - not symmetrical at the base with pinnate venation with the secondary veins ending in the teeth. Flowers are bisexual or unisexual (monoecious, dioecious, or polygamous), inconspicuous, wind-pollinated. Fruits are flattened, disc-like samaras comprising a seed cavity surrounded by a thin wing. Ulmus americana the American elm Occupies variable habitats from the Great Plains to the east coast of the US but is most common on well-drained bottomlands. On seasonally wet flatlands associates include red and silver maples, swamp oaks, black ash, willows and poplars. Attains best growth on well-drained bottomlands in association with sweetgum, green ash, basswood and other hardwoods. Found in association with cottonwoods, box-elder and green ash along streams on the western edge of its range. Has been eradicated from much of its former range due to Dutch elm disease, which is caused by the fungus Ceratocytus ulmi that seals off xylem elements. Fungus is spread by the scolytus beetle and by root connections between neighboring trees. Several resistant cultivars have been bred. Was a very common street tree before Dutch elm disease. Leaves are simple, alternate, deciduous, 3-6" long, oblong-obovate to elliptical with a doubly serrate margin, acuminate apex, oblique base and a sandpaper like texture. Trees tend to be vase shaped with large stout branches terminating in slender drooping limbs to form a symmetrical round-topped crown. Mature trees often have buttressed bases. Typically has a shallow, wide-spreading root system. Bark is grayish and is separated into fissures on mature trees. 124

10 Monoecious, flowers before leaf buds break. Borne on long pedicles in fascicles of 3-4. Fruits are approximately 1/2" long, ciliate, flattened, oval samaras with a notch on the apex. Ulmus pumila: Siberian elm A large shrub or small tree native to Asia but has been widely introduced throughout temperate regions. A very common windbreak planting, especially in arid & agricultural areas. Resistant to Dutch elm disease. Prolific seeder invades open land. Leaves are simple, alternate, deciduous, 1-3" long, elliptical and only slightly oblique at the base with a singly serrate margin. Most elms are doubly serrate. Fruit is approximately 1/2" long glabrous samara with a deep apical notch. 125

11 Cannabaceae s.l. Woody members of Cannabaceae (which is traditionally restricted to Cannabis and Humulus) at one time were included in the Ulmaceae (subfamily Celtidoidaea) or separate family (Celtidaceae), now found to be most closely related to traditional Cannabaceae. Can be distinguished from Ulmaceae s.s. by: Secondary veins not terminating in the teeth, but rather forming a series of loops Fleshy fruits (drupes) as opposed to samaras (Drupe = fleshy indehiscent fruit with a stony endocarp surrounding a usually single seed - as in a peach or cherry) Series of other characters including secondary chemistry, pollen architecture, and base chromosome number Celtis reticulata netleaf hackberry A small scraggly tree or large shrub widely distributed throughout the west but never abundant. Occurs in river canyons of the Inland northwest including, the Snake, Salmon and Columbia. Also occurs on bluffs and semi-desert plains. Has been used for posts, furniture, fuel and barrels. May reach 7-20' (30-40 max) tall and 1-2' diameter at maturity. Leaves are simple, alternate, decisuous, 2-4" long, ovate with conspicuous net-like (reticulate) venation patterns and margins with widely spaced teeth. Twigs with chambered pith Bark is tan to gray with conspicuous warting on younger trees, but becomes corky and ridged on older trees. Monoecious, small flowers borne in leaf axils inconspicuous and wind pollinated. Fruit is a drupe about 1/4-3/8" long with sweet flesh. 126

12 (Celtis occidentalis hackberry) Widely distributed in the eastern United States from the southern New England States through central New York west in southern Ontario to North and South Dakota. Larger tree than western counterpart up to 60 ft. tall. Leaves are simple, alternate, decisuous, 2-5" long, ovate with conspicuous net-like (reticulate) venation patterns and a serrate margin. Twigs with chambered pith Bark is tan to gray with conspicuous warting on younger trees, but becomes corky and ridged on older trees. Monoecious, small flowers borne in leaf axils inconspicuous and wind pollinated. Fruit is a drupe about 1/4-3/8" long with sweet flesh. 127

13 Moraceae mulberry or fig family Ca. 50 genera and 1500 species of trees, shrubs, vines. Primarily distributed in the warmer regions of the world, but with several temperate species. Ficus (figs) is the most diverse genus with over 800 species mostly tropical and shows an amazing array of growth forms from epiphytes, vines, shrubs, small trees, shrubs etc. to large trees. Closely related to Ulmaceae and Cannabaceae and has similar small, mostly wind-pollinated flowers. Ficus is an exception and has specialized, coevolved fig-wasp pollinators. Vegetatively they all have milky latex distributed throughout the plant. 8 genera are found in North America they are small medium sized trees commonly used ornamentally. Tropical trees are important for timber, edible fruits (figs), paper fibers, and dyes. Morus alba white mulberry Of the 10 species of Morus 2 are native to US and 2 others have naturalized we will look at one of the naturalized species, but very similar to natives Native to China introduced in the in early 1600 s to try to establish a silkworm industry didn t work. Naturalized throughout the US and southern Ontario and has become weedy in disturbed areas particularly at the urban-wild interface. A small tree up to 40 feet tall, branches low and develops a wide spreading crown Vegetative features: Leaves simple, alternate, deciduous, stipulate, roughly orbicular in shape, 3 to 6 inches long with a serrate margin, often irregularly lobed, smooth above. Milky latex evident in broken petiole of young leaves. Bark orange-brown with lenticels when young, becoming gray with long narrow irregular ridges. Reproductive features: Normally dioecious flowers small, green catkins, male flowers narrow, 1 to 2 inches long; female flowers plump, 1 inch long Fruit resembling blackberries, cylindrical, 1 to 1 1/4 inch long, fleshy multiple of drupes, pale pink to dark red, not as juicy as red mulberry (Morus rubra) 128

14 Maclura pomifera Osage orange Maclurais a monotypic genus. The single species has a very restricted native range southern Arkansas, southern Oklahoma, and northeastern Texas, but is widely planted throughout the US and Canada as an ornamental. The wood is among the most decay resistant in North America and has a characteristic bright yellow-orange color. Attempts to plant only males ornamentally because of characteristic large, heavy, fruit but fruit is really the most interesting part! A medium sized tree with a short trunk. The crown is irregular, with stiff, spiny branches. Vegetative features: Leaves alternate, simple, pinnately veined, 2 to 5 inches long, oblong to ovate with an acuminate tip, margins entire, upper surface shiny. Twigs are armed with stout, unbranched thorns at each leaf scar. A milky sap is exuded when cut. Bark orange-brown, developing scaly ridges with irregular furrows. Reproductive features: Dioecious; flowers inconspicuous. Females is borne in dense, globose, clusters. Male borne in subglobose racemes. Fruit a large, round multiple of drupes 4 to 5 inches in diameter, with a very distinctive citrus smell; the outer surface looks like "brains"; when crushed, a white, milky juice is exuded. 129

15 Anacardiaceae - the cashew family Includes approximately 70 genera and 875 species of trees and shrubs primarily in the warmer regions of the world. Many species are commercially important; Anacardium occidentale, cashews; Pistacia vera, pistachios; and Mangifera indica, mangos. Others of the genus Toxicodendron cause severe contact dermatitis. We ll look at two genera Rhus (sumacs) and Toxicodendron (poison ivys) - Rhus and Toxicodendron have often been confused some botanists treating as one genus but, fruits of Rhus are glandular pubescent and red, fruits of Toxicodendron are glabrous and greenish-white. In addition the resins of Rhus are not poisonous while Toxicodendron contains urushiol and causes contact dermatitis. All members of Anacardiaceae that have cream colored, glabrous drupes and the oil urushiol that causes contact dermatitis in humans were reclassified into the genus Toxicodendron about thirty years ago. Rhus glabra - smooth sumac A shrub or small tree primarily of the eastern US but scattered widely in the west as well. Occupies open woodlands, clearings, roadsides and waste places. May reach 4-15' tall and 1-4" diameter. Usually a many-trunked small tree or large shrub. Deciduous, alternately arranged pinnately compound leaves are 1-2' long with lanceolate leaflets that have serrate margins. Turn red in fall. Stems have large pithy core. Limbs are glabrous and glaucescent. They have milky sap and small, scaleless buds. Bark is gray-brown and smooth, but becomes scaly on older plants. Dioecious, female flowers are small, white and are borne in terminal panicles. Fruits are 1/8" long, hairy, red drupes that may remain on the tree for several months. 130

16 Rhus typhina - smooth sumac A shrub or small tree primarily of the eastern US but scattered widely in the west as well. Occupies open woodlands, clearings, roadsides and waste places. May reach 25' tall and 1-4" diameter. Branches repeatedly and widely forked crown. Usually a many-trunked small tree or large shrub. Deciduous, alternately arranged pinnately compound leaves are 1-2' long with lanceolate leaflets that have serrate margins - rachis pubescent. Turn red in fall. Stems have large pithy core. Limbs are densely pubescent resembling deer antlers in velvet. They have milky sap and small, scaleless buds covered in soft hairs. Remaining pubescent for several years, turning gray-brown and much later becoming a bit scaly. Dioecious, female flowers are small, yellow-green and are borne in terminal panicles. Fruits are 1/8" long, hairy, red drupes that may remain on the tree for several months. Toxicodendron radicans poison-ivy A catch-all for several taxonomically troublesome and highly variable species. Toxicodendron: Includes T. vernix, poison sumac; T. diversilobum, the Pacific poison oak, T. radicans, the climbing poison-ivy. Collectively they occupy much of the US except major mountain ranges and deserts of the west. Contact dermatitis is caused by the oil urushiol which initiates an autoimmune response. Some people appear to be resistant but become sensitive with repeated exposures. Severe rashes requiring hospitalization and treatment with steroids are common. Deaths have been recorded. All are deciduous with compound leaves. T. vernix has pinnately compound leaves with 5-13 leaflets (like Rhus) all others have trifoliate leaves although some will occasionally have 5 leaflets. Leaflets of three leave them be. May be present as a low (6 to 18 inches), spreading "carpet" on the forest floor, as a climbing vine, or as a bush, or small shrub (T. vernix). Monoecious small, yellowish-green flowers arranged in a panicle Fruit a cream-colored drupe, ¼ inch in diameter arranged in panicle. 131

17 Elaeagnaceae the oleaster family Includes 3 genera and approximately 45 species of shrubs and trees in warm temperate and subtropical regions. They have lepidote scales scale-like hairs on leaves, twigs and fruits shiny/silvery appearance. Root nodules with nitrogen fixing bacteria. Four species are native to N. America. (Elaeagnus commutata native to NW US). Elaeagnus angustifolia Russian-olive A small tree native to southern Europe and western and central Asia, but has been widely introduced. Often planted in windbreaks and for erosion control in N. America and has escaped locally. Very common along irrigation ditches, pastures and abandoned fields in the west. Has naturalized over much of the arid west and Great Plains, often displacing native species along streams and irrigation canals displacing Salix exigua on lower clearwater. Leaves are simple, alternate, deciduous, 1 to 3 long, 1/2 inch wide, linear-lanceolate, entire margin; dull green to almost gray and distinctly scaly above, silvery and scaly below. Young branches are silvery and scaly, and may bear thorns. Later developing a shiny light brown color Fissured brown bark. Ragged form and silvery foliage is very distinctive. Flowers axillary, bell-shaped (campanulate), 3/8 to 5/8 inch long, very fragrant, yellow - lacking petals. Fruits are drupe-like achenes. Yellow-pink, edible and sweet but dry. 132

18 Rosaceae the rose family Includes ca. 95 genera and 3,000 species of trees, shrubs, herbs and vines widely distributed throughout the world but are most prolific in the temperate regions cosmopolitan, but most abundant in the Northern Hemisphere. Herbaceous members grow in wide variety of habitats including, temperate forest understory, salt & freshwater marshes, arctic tundra, old fields, and roadsides. Woody members, such as Rubus (blackberries and rasberries), Crateagus (hawthorns), Amelanchier (serviceberries), and Prunus (cherries), are prominent in early stages of succession many understory shrubs and small trees. Tree species, like Prunus serotina may be components of mature deciduous forests. Only the genus Prunus is significant in timber production but several are sources of commercially important fruits and are popular ornamentals; apples, pears, peaches, plums, apricots, almonds, strawberry, raspberry, and others. 10 arborescent genera are native to the US. In Rosaceae, the flowers are all pretty much alike, but fruit types differ greatly and form the basis of traditional subfamilial divisions. Rosaceae - Rose family (95 gen/2825 spp) 1) plants woody or herbaceous 2) leaves often compound, but sometimes simple (the species we ll look at have simple lvs) - stipules present often quickly deciduous on woody members, but will leave scars) - leaves and/or leaflets with serrate margins - alternate arrangement 3) Flowers - actinomorphic - sepals and petals in 5s - stamens many - Hypanthium usually present - ovary superior, inferior, or half inferior Most striking variation in reproductive morphology is in fruit type. Traditional view of divisions within family: Subfamilies are based on fruit type Chromosome number correlates somewhat but is more variable 133

19 Subfamilies Gynoecium Fruit type Chromosome # Spiraeoideae Rosoideae Apocarpus (carpels free), 5 separate carpels, superior Apocarpus, many separate carpels, superior Follicle or capsule X=8, 9 Achene or drupelet (little drupe) X=7,9 Prunoideae 1 carpel, superior Drupe X=8 Pomoideae (Maloideae) Syncaprous (compund pistil), 5 fused carpels, inferior Pome (apple) a fleshy indehiscent fruit, derived from a inferior compound ovary consisting of a modified floral tube surrounding a core X=16,17 However, recent studies (some from WSU) have shown that some of the subfamilies based on fruit type are not all monophyletic and that chromosome number is a better indication of phylogeny see overhead Phylogeny: Subfamilies Prunoideae and Pomoideae (Maloideae) are monophyletic, whereas Rosoideae are polyphyletic, and Spiraeoideae are probably the ancestral paraphyletic group in the Rosaceae. 134

20 Pomoideae (Maloideae): Includes ca. 25 genera and 1,000 species. Flowers with inferior ovary hypanthium fused to ovary wall, with 5 connate carpels (with 1-many ovules) surrounded by a hypanthium. Resultant fruit is called a pome. Examples include apples and pears. We eat the swollen hypanthium. Includes the genera Malus, Pyrus, Amelanchier, Crataegus and Sorbus. Amelanchier The genus includes 10 species native to N. America with at least 1 in every American state and Canadian province. Pomes are sweet and are important sources of food for wildlife and historically for humans. Amelanchier alnifolia serviceberry Occupies variable sites from bunch grass to the lower subalpine zone of the northern and central Rockies, Cascadian region and the northern Plains. Several varieties exist although there is little agreement on taxonomic placement. Usually has a many-trunked shrubby appearance but it can reach 30' tall 8" diameter. Simple, alternate, deciduous, 1-2" long, oval with the apical half with a variably serrate/toothed margin and the basal half with an entire margin. Lateral veins have a herringbone pattern. Bark is smooth and gray. Inner bark has a very bitter odor. One of the earliest native shrubs to flower in our area. Has showy white flowers in terminal clusters emerging with the leaves. Inferior ovary hypanthium fused to ovary wall, many stamens. Fruit is a 1/4-1/2" purple, sweet pome with several large seeds. Distributed by numerous wildlife. Very popular with birds and bears. Crataegus the hawthorns A taxonomically challenging genus of shrubs and small trees that includes ca. 265 species widely scattered in Europe, Asia and N. America with 35 species native to the US. Extremely complex geographic patterns of variation exist. Hybridization is common and probably contributes to these confounding patterns. All have thorns (sharp modified branches) and pomes for fruit. Consequently, the hawthorns are very easy to identify as a group but are difficult to tell apart. 135

21 Crataegus douglasii - black hawthorn A small tree that occupies moist soils of riparian zones and lower slopes from shrub steppes to mid elevation coniferous forest. Common on disturbed sites, especially old pastures. Frequently has a many-trunked shrubby form or a scraggly form with a short trunk with stout low-spreading branches and a round-topped crown. May reach 30' tall and 1' diameter at maturity. Leaves are simple, alternate, deciduous, 1-3" long, ovate-obovate with a sharply toothed margin that is slightly lobed on the apical half. Conspicuous stout thorns to 1"-2.5 long, ouch! Bark is gray and smooth on young trees, but brown, furrowed and scaly on older trees. White flowers in clusters. Inferior ovary hypanthium fused to ovary wall, many stamens. Fruits are red to dark purple-black ca. 1/2" pomes with several seeds. Edible but dry and not real tasty. Highly variable and taxonomically challenging secies - includes C. columbiana, which some people split out. 136

22 Prunoideae: Flowers with superior ovary, monocarpus with one ovule = 1 fruit and 1 seed per flower. Fruit is a drupe, eg. cherries, plums, peaches, apricots and others. The ovary swells and becomes fleshy. The hypanthium is not involved! Includes the genus Prunus. Prunus Includes over 200 species of trees and shrubs widely-scattered throughout the cooler regions of the Northern Hemisphere. Several are commercially important fruit trees; P. domestica, garden plum; P. persica, peach; P. avium, sweet cherry and many others. Most have simple alternate, deciduous leaves (rarely persistent), elliptical, toothed margins with 2 glands on the petiole or base of the leaf. Most have hydrocyanic acid in the inner bark and foliage; has a bitter almond odor. Flowers: superior ovary, 1 carpel with one ovule (i.e., 1 simple pistil). Fruit is a drupe. The ovary swells and becomes fleshy. The hypanthium is not involved! Prunus virginiana common chokecherry A small tree or shrub that occupies variable sites from as far north as Hudson's Bay to the central hardwoods in the east and the intermountain region in the west. A huge geographic range. Occurs from low elevation to montane habitats. Leaves are simple, opposite, deciduous, 1 1/2-3 3/4" long, elliptical with a sharply serrate margin and glands on the petioles. Variably pubescent or glabrous. Bark is grayish and generally smooth but often with a coarse texture. Flowers are white, many stamens with hypanthium, single pistil, superior ovary Inflorescence a cylindrical raceme. Fruits are red-black drupes ca. 1/4-1/2". Also spreads by rhizomes, frequently forming thickets Drupes are bitter and astringent before they are fully ripe. Much better after the first frost in early fall. Fruits and pits have hydrocyanic acid, poisonous in quantity. Leaves can poison livestock. Variation over enormous geographic range has led to taxonomic difficulties...several varieties have been suggested. 137

23 Spiraeoideae: Includes ca. 17 genera and 140 species. Flowers with superior ovary, with 5 free carpels and many ovules. Fruits are many seeded follicles. Includes the genera Physocarpus and Holodiscus. Holodiscus discolor - oceanspray Occurs throughout western North America from the Rockies west to Pacific. Dominant or subdominant understory shrub in a variety of habitat and community types throughout the Pacific Northwest from climax forests with moist, deep soils to droughty timbered or talus slopes - coastal bluffs and mountains to the dry, coniferous forest types of the Intermountain region Typically an erect, loosely branched shrub growing to 15 feet tall with multiple, straight stems arising from the base. Arborescent coastal forms may reach heights of approximately 20 feet. Leaves alternate, simple, deciduous; 3/4 to 2 1/2 inches long, ovate, and either coarsely toothed or lobed and serrate; entire near the base. prominently pinnately veined. Bark smooth and gray-brown Flowers very small creamy white, superior ovary with 5 separate carpels. Inflorescence a large, loose, panicle (branched raceme). Fruit are tiny, light brown, 1-seeded follicles borne in large clusters; fruit clusters persist through the winter and into the next growing season. Physocarpus malvaceus mallow ninebark Generally occurs east of the Cascades, from south-central British Columbia to central and eastern Washington and Oregon; east to southwestern Alberta, Idaho, Montana, Wyoming, Nevada, and Utah. Very common understory shrub found in a wide variety of habitat types from cool/moist subalpine communities to more mesic Douglas-fir (Pseudotsuga menziesii) and drier ponderosa pine (Pinus ponderosa) sites. Often found growing with Holodiscus discolor. A medium sized, vase-shaped shrub up to 5-10 Leaves alternate, simple, deciduous, maple-like, palmately 3 lobed (occasionally 5); almost circular in outline, 1 1/2 3 in diameter, blunt serrated margin; dark green above, paler and pubescent below. Bark thin and yellow-, orange-, or red-brown; shredded and exfoliating in long strips, especially on older stems 138

24 Reproductive features: Flowers small (1/2 inch) white to faint pink flowers, superior ovary with 5 separate carpels. Inflorescence a small, dense, upright, round-topped cyme. Fruits small (1/4 inch long) pointed follicles borne in dense, upright hemispherical clusters, initially they are red and later turning a bright reddish brown. Rosoideae: Includes ca. 50 genera and 1800 spp. superior ovaries and apocarpus. eg. Rosa (roses), Frageria (srawberries), Rubus (raspberries and blackberries) and others. 139

25 Fabaceae the legumes Includes ca. 642 genera and 17, 275 species widely distributed throughout the world. Many have root nodules containing nitrogen-fixing bacteria...key components involved in nutrient cycling symbiosis with Rhizobium N-fixing bacteria allows them to be excellent colonizers of waste/disturbed areas that are low in N. The legumes are second in economic importance only to the grasses. They are important sources of food, pharmaceuticals, pesticides and lumber. In Rosaceae, the flowers were all pretty much alike, but fruit types differed greatly and formed the basis of subfamilial divisions - in Fabaceae, fruit types are all similar - the legume - but flowers differ greatly and form the basis of subfamilies. Fabaceae (Leguminosae) - Pea or legume family (642 gen/18,000 spp) 1) mostly woody tropical trees, but in temperate zone mostly herbs 2) Commonly associated with N-fixing bacteria as symbionts in roots (Rhizobium) 3) Leaves compound - margins entire - stipules present 4) Flowers - actinomorphic or zygomorphic - sepals and petals in 5s - stamens usually 10 or many (Mimosoideae), sometimes diadelphous (9 fused and 1 free) - ovary superior - fruit a legume (specific type of follicle) Papilionoid flowers are typical pea Flag flowers, with two lower petals fused to form a keel and with diadelphous stamens (9 fused and 1 free) Flag Flower wing Banner keel 1 free stamen wing 9 fused stamens Caesalpinoid flowers also often are flag flowers, but the lower petals are NOT fused and the stamens are not fused Mimosoid flowers are called brush flowers, because they have many stamens that are exerted on long filaments and form a brush that covers visiting insects or birds with pollen. 140

26 In contrast to the Rosaceae, major variation is in floral morphology, while fruit type is constant: Subfamily stamens fruit flower type Mono/Para? Mimosoideae: many legume Brush flowers Monophyletic Caesalpinoideae: 10-free legume Flag flowers Paraphyletic Papilionoideae: diadelphous legume Flag flowers Monophyletic Phylogeny: Subfamily Caesalpinoideae is ancestral (paraphyletic) within the Fabaceae and subfamilies Mimosoideae and Papilionoideae are monophyletic and are derived from Caesalpinoid ancestors. Subfamily Caesalpinoideae Gleditsia triacanthos the honeylocust Occupies diverse sites from mesic bottomlands to limestone uplands. Natural range includes the central and southern hardwoods. Notably absent from the east coast and the northern deciduous zone, but has been widely planted as a shade tree and in windbreaks. May reach 70-80' tall and 2-3' diameter at maturity. Leaves are pinnately or bipinnately compound, alternate and deciduous. Leaflets have a more or less acute apex entire margin. Bark is grayish brown and broken into superficially scaly ridges separated by fissures. Twigs and bark often have abundant thorns up to 3" long with some thorns branched. Like the rest of Caesalpinioideae, it has a zygomorphic flower with the upper petal in between the laterals and the two lower petals distinct. Flowers are whitish green. Fruit is a brownish legume 6-18" long. An extremely important ornamental with many thornless and fruitless varieties. Wood is used locally. No root nodules. 141

27 Subfamily Faboideae Robinia pseudoacacia black locust Native to the east-central US but has been widely introduced over much of N. America, Europe and Asia. Has been planted widely and is capable of growing on degraded soils with little moisture. Has naturalized in many areas, like the lower Snake River. Occupies diverse sites but most commonly occurs on uplands in the Appalachians and Ozarks May reach 40'-60' tall and 1-2' diameter at maturity. Leaves are pinnately compound, alternate and deciduous. Leaflets have a rounded apex. Upper branches of mature trees and vigorous twigs have stipular spines. Bark is nearly black with deeply furrowed interlacing ridges. Has root nodules that contain N-fixing bacteria. Has whitish flowers that are strongly zygomorphic with the upper petal outside of the laterals and the lower petals fused like the rest of subfamily Faboideae typical flag flower. Fruits are brownish legumes ca. 2-4" long. 142

28 Rhamnaceae the Buckthorn family Rhamnus buckthorns 125 species cosmopolitan. 12 species native to North America, but only 5 are arborescent (rest shrubs) Rhamnus purshiana is an important tree in the PNW. Rhamnus purshiana Cascara Native to western North America from southern British Columbia south to central California, and inland to western Montana It grows in moist, acidic soils in the shady side of clearings or in the marginal forest understory, near the edges of mixed deciduous-coniferous forests. It typically grows as a second-generation tree after alders have colonized a barren plot of land. Occasionally growing up to 60 feet tall, though more commonly a large shrub or small tree ft tall, with a trunk in diameter. Leaves simple, alternate, deciduous; elliptical to oblong-ovate, 2 6 long finely serrate or entire, dark shiny green on top, pubescent and paler green below. Pinnate secondary veins conspicuous, parallel with a slight upward curve at end. Twigs with naked, tomentose buds and elevated leaf scars Bark smooth, becoming scaly with age. Reproductive features: Flowers small, arranged in axillary cymes, yellowish-green, 5-parted. Fruit globose berry with several (3) seeds, bright red at first, quickly maturing to blueishblack. The dried, aged bark of this tree has been used continually for at least 1,000 years by both native and immigrant Americans as a laxative natural medicine, commercially called "Cascara Sagrada", but old timers call it "chitticum bark". Cascara Sagrada means "sacred bark" in Spanish. The much more pertinent name chitticum means "shit come" in Chinook Jargon; chittam comes from the Chinook Jargon phrase chittam stick = "laxative tree" which is similarly from the English word "shit". 143

29 Lecture: Asteridae s.l. The traditional, or core, Asteridae included families with the above characters, but only those also with: - gamopetalous (fused petals) corollas - 5-parted flowers - epipetalous stamens - 2 fused carpels Families with many of these traits, but with polypetalous corollas, typically were assigned to the Rosidae (e.g., Cronquist). - Examples include Apiaceae, Cornaceae, Hydrangeaceae, Loasaceae Cornaceae the dogwood family Includes 7 genera and approximately 110 species of trees, shrubs and a few herbs bunchberry (Cornus canadensis). Nearly all are native to the Northern Hemisphere and very diverse in China. 2 genera Cornus and Nyssa (7 spp., 4 native to SE US) are native to the US. Cornus the dogwoods Includes approximately 65 species, all but one (Peruvian) in the Northern Hemisphere with 16 species native to the US. Several riparian species are important in erosion control. Many are important as ornamentals. Cornus means horn in Latin and refers to the very hard wood characteristic of the genus. Leaves are simple, opposite, and deciduous with entire margins and arcuate venation in most species. Veins with helical thickenings Cornus test. Flowers are small, 4-parted, in various clusters, sometimes subtended by showy bracts, inferior ovaries. Fruits are drupes with a 2-seeded endocarp. 144

30 Cornus florida - flowering dogwood A small shrubby tree of the eastern US. Shade tolerant understory species and attains best growth on well-drained friable soils in association with several hardwoods. A very important ornamental with many cultivars. May reach 40' tall and 12-18" diameter at maturity. Leaves are 2 1/2-5" long, simple, opposite, deciduous, and elliptical to ovate with arcuate venation and an entire margin. Turn red in the fall. Usually as several wide-spreading branches with a low dense crown opposite branching gives candelabra form. Bark is broken up into small brown-black plates on mature trees. Few, small, perfect, 4-parted flowers with inferior ovaries arranged in heads subtended by 4 notched, showy, white-pink bracts. Fruits are oval shaped drupes in heads of 5-6, red at maturity, with oval grooved stone. Cornus nuttallii Pacific dogwood Occupies moist slopes and valleys in the understory of conifers along the Pacific slope from British Columbia to southern California. Disjunct on the Lochsa and Selway rivers in central Idaho. A very popular ornamental on the west coast. May reach 60' tall and 12-20" diameter at maturity. Leaves are 2 1/2-4 1/2" long, simple, opposite, deciduous and ovate-elliptical with arcuate venation, margin may be sparsely toothed or entire. Leaves turn red in the fall. Has a straight trunk and narrow crown in forested conditions but tends to have several wide-spreading branches and a lower rounded crown when grown in the open - sometimes is many-trunked and bushy. Bark is dark and broken into small plates at maturity. Many yellowish-green, small, perfect, 4-parted flowers with inferior ovaries arranged in dense in heads, subtended by 4-7 showy white-pink, petal-like bracts that are not notched at the apex. Fruits are drupes in heads of 30-40, red at maturity and they have smooth stones. 145

31 Cornus sericea red-osier dogwood (Cornus stolonifera) Occupies riparian zones and cool moist forest understory throughout much of northern North America and scattered along watercourses throughout the west. Important species along with many willows in river stabilization/erosion control. Common ornamental because of red stems and red-orange fall color. Typically a thicket-forming shrub with many stems and under 10 tall, but in some of Idaho s warmer canyons can reach 15 tall and 3 diameter. Leaves are 2-4" long, simple, opposite, deciduous and somewhat narrow ovate-lanceolate with entire margin. Twig bright red, sometimes green splotched with red, white pith. Bark red to green with numerous lenticels; later developing larger cracks and splits and turning light brown. Flowers small, small, perfect, 4-parted, with inferior ovaries, dull-white in cymose clusters about 2 inches across. Fruit a dull white to blueish drupe, 1/4 to 1/3 inch in diameter in rounded clusters. Hydrangeaceae Hydrangea family 17 genera/220 species widespread but characteristic of temperate to subtropical regions of northern Hemisphere. 5 genera in North America. Woody with opposite leaves similar to Cornaceae, typically shrubs and small trees with capsular fruits. Philadelphus lewisii mockorange (Syringa in these parts) Native to western North America, from northwestern California in the Sierra Nevada, north to southern British Columbia, and east to Idaho and Montana. It is widespread but not terribly common, usually appearing as an individual plant amongst other species. It was discovered by Meriwether Lewis in A loosely branched shrub up to 12 feet tall. Native American tribes used P. lewisii for numerous purposes. The hard wood was useful for making hunting and fishing tools, snowshoes, pipes, and furniture. The leaves and bark, which contain saponins, were mixed in water for use as a mild soap. Other common names include "wild mock-orange" (though this can apply to any species in the genus), and "Syringa", a confusing name as it usually refers to the unrelated lilacs. 146

32 Leaves opposite, simple, deciduous, ovate, 1-3 long, green above and paler below, margins nearly entire with a few glandular teeth on each side. Passes the Cornus test so beware!!! Twig slender, opposite, tan, and widely dichotomous. Bark light brown and shreddy. Flowers perfect, 4-petals and numerous stamens with inferior ovary, showy, white, solitary or clustered, about 1 inch in diameter, fragrant. Fruit small, brown, hard, 4-celled capsule, ¼ in diameter. Oleaceae the olive family Includes 24 genera and 615 species of trees and shrubs primarily in the N. Hemisphere. The genera Olea and Fraxinus produce excellent timber and Olea europaea is the source of olives of commerce. Syringa lilacs very common ornamental shrub/small tree. Four genera are native to N. America but only Fraxinus is an important timber species. Fraxinus - the ashes Includes ca. 65 species primarily of the temperate regions of the northern Hemisphere but also occurring in Java and Cuba. ca. 17 species are native to the US. Important sources of high quality hardwood. Leaves are pinnately compound, opposite and deciduous. Variably monoecious or dioecious but the species we cover is dioecious. Flowers are inconspicuous, unisexual all North American species lack a perianth and are wind pollinated flower before leaves etc. stamens 2-4, pistil 1 with 2-celled ovary female flowers in loose panicles, male flowers in tight clusters. Fruits are 1-seeded samaras comprising an elongated seed at one end and an elongated terminal wing. Look a bit like a canoe paddle. 147