Monday, Week 13 Announcements: Extra credit lecture Dr. Amy Zanne Biology Seminar, T 12:30, REN 125

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1 Monday, Week 13 Announcements: Extra credit lecture Dr. Amy Zanne Biology Seminar, T 12:30, REN 125 Finish Monocot/ dicot Traditional primary division is between Dicots and Monocots Dicots Monocots # cotyledons 2 cotyledons 1 cotyledons stem ring of vascular bundles scattered vascular bundles vascular cambium often present no vascular cambium habit woody or herbaceous primarily herbaceous (no true wood) leaves simple or compound usually simple venation net veined, pinnate, palmate parallel (or striate) flower parts parts in 4 s, 5 s, or parts in 3 s pollen monosulcate or tricolpate monosulcate Because of their lack of true wood, trees in the sense of having secondary xylem do not occur in however, several monocot groups have a tree-like habit (e.g., bamboo, palms, and so we ll look at a couple. Arecaceae the palm family ~200 genera and over 2000 species and is pantropical in its distribution with a few in the subtropics and warm-temperate latitudes. Only about 10 genera are native to the US, with one in the southwest the rest in the southeast. Arecaceae is one of the three most important plant families (along with legumes and grasses) economically shelter, construction materials, furniture food, fiber, wax, and oil Evergreen trees, shrubs, and lianas (woody vines) Usually unbranched trunks primary growth only no true wood or bark, much of the bulk of the trunk is made up of overlapping leaf bases Leaves peresistant, alternate, often very large, forming dense terminal rosettes, longpetiolate, with a broad to tubular sheath. Leaves are simple, but mechanically split into narrow segments at maturity either pinnate or palmate Flowers are small, fragrant, perfect or imperfect, regular, flower parts in 3s. Fruit a fleshy or fibrous drupe 77

2 Washingtonia filifera California fanpalm Distributed in southwestern Arizona, southeastern California and south into Mexico moist soils along streams in narrow mountain canyons and oases. This is the largest native palm of the US and only native to southwestern US, widely cultivated. Named for George Washington. Commonly reaches 75 tall and 3 in diameter Leaves fan-shaped (palmate), 3-5 in diameter, petiole 3-5 feet long with hooked prickles below. Old dried leaves hang down around trunk forming a skirt Poaceae grass family Huge family with 700 genera and 10,000 spp. economically most important family of plants (corn, wheat, rice, ) Primarily herbaceous except for bamboos form tropical and subtropical forests, but are also cultivated as ornamentals in the US. Some have become pests although usually no sexual reproduction in temperate regions, spread rapidly by underground stems rhizomes that are difficult to contain. Bamboos are perennial, of tree size can be up to 100 tall and woody, but no secondary growth! Stems are hollow in internodes Leaves alternate, sheathing at base, blades flat, long, strap-like often narrow and jointed between blade and sheath. Woody Magnoliids Magnoliales and Laurales These relatively basal dicots share some primitive traits in angiosperms - gynoecium usually composed of unfused carpels (simple pistils) - superior ovary(ies) - sepals and perianth usually not differentiated; parts then called Tepals 78

3 Wednesday, Week 13 Announcements: Quiz in lab next Wed through Betulaceae. Exam Friday. Woody Magnoliids Magnoliales and Laurales These relatively basal dicots share some primitive traits in angiosperms - gynoecium usually composed of unfused carpels (simple pistils) - superior ovary(ies) - sepals and perianth usually not differentiated; parts then called Tepals Magnoliales Magnoliaceae (7 gen/165 spp) 2 genera and 9 species native to N.Am. 1) woody trees or shrubs; may be evergreen or deciduous 2) ethereal (aromatic) oils primitive smell when leaves are crushed 3) simple leaves with pinnate venation and entire margin 4) large showy flowers - always bisexual - many parts, spirally arranged; borne on elongate receptacle - sepals and petals poorly differentiated - laminar stamens poorly differentiated into anther and filament - ovary superior - fruit usually a follicle (often many aggregated together) or samara - follicle dry, dehiscent, 1-carpellate fruit that dehisces on one side - samara dry, indehiscent, 1-carpellate winged, fruit We ll look at one species from each of the two genera native to N. Am. Magnolia leaves unlobed, apex acute to obtuse, base cunneate to auriculate, fruit is aggregate of follicles. 120 species with 8 native to eastern US. Liriodendron leaves lobed, apex truncate to emarginate, base rounded to truncate or slightly cordate. Fruit and aggregate of samaras. Once widespread and more species rich in fossil record, now only 2 species. 1 in central China and 1 in eastern US. Magnolia grandiflora southern magnolia, evergreen magnolia Medium-sized tree ( tall and 2-3 ft diameter) native to the southeastern US from sea level to ca. 400 ft in well-drained soils. Widely cultivated and has naturalized along eastern seaboard as far north as Maryland by escaping cultivation. Evergreen habit with persistent, shiny green leaves that are dark brown/bronze below, and aggregate of follicles fruit make this very recognizable tree. 79

4 Liriodendron tulipifera yellow poplar Distinctive tree distributed throughout eastern North America can reach 175 tall and in diameter and 400 years old. One of the most valuable in terms of timber production in the eastern US and therefore, very little old-growth remains (one pocket in NC is last unharvested grove). Especially fast growing on good sites, but outcompeted by other hardwood species on poor soils. Site specific and intolerant. Laurales - another group of phylogenetically basal woody dicots Lauraceae - most well-known family of Laurales (52 gen/2850 spp) - very diverse in tropics, but a few temperate species. Well known for aromatic (ethereal) oils in leaves, bark, fruits. Some important members include Cinnamomum cinnamon, camphor, Laurus bay laurel, Persea Avocado, Sassafras and many ornamentals Trees or shrubs (occasionally vines, including the parasitic vine Cassytha) Ethereal (aromatic) oils present ( primitive smell) Leaves simple (occasionally lobed), alternate and spiral, entire, pinnate venation. Flowers bisexual or unisexual (then dioecious), actinomorphic, usually small; tepals usually 6; stamens 3-12 (in whorls of 3); anthers opening by 2-4 flaps; one carpel with single ovule; ovary superior Fruit a drupe, or less often a one-seeded berry Umbellularia californica California laurel, California bay Only species of Lauraceae in western North America. Distributed from southwestern Oregon through the coast ranges and lower Sierra Nevada to southern California. Dry rocky slopes and bluffs, as well as moist bottomlands from sea level to ca ft in North, 2000 to 6000 ft in south. On moist sites in southwestern OR it can be a large tree (in Sequoia sempervirens forests) ft tall and 3-10 ft in diameter, although elsewhere in range it is usually a small to medium sized tree ft tall and in diameter. Commonly shrubby on windswept bluffs of the Pacific. Evergreen leaves have a very strong odor hen crushed. 80

5 Wednesday, Week 13 Announcements: Quiz in lab next Wed through Betulaceae. Exam Friday through next Monday. Finish Pinus strat with Pinus palustris video, because won t get to SE pines and this is the most important species/community type. Subg. Pinus cont d Pinus resinosa red pine Occupies variable sites of the northern deciduous zone. Attains best growth in the upper Great Lakes region on lightly-acidic, sandy soils that are not capable of supporting Pinus strobus. Intermediate in drought tolerance not as tolerant as Pinus banksiana but more so than Pinus strobus. Less shade tolerant than P. strobus more so than P. banksiana. These three species overlap broadly in their ranges, but are a good example of closely-related species that have evolved to occupy different/complimentary ecological niches. Common evolutionary pattern. May reach 110 tall ad 2-3 in diameter. Distinctive shape with symmetrical, oval crown and long, straight trunk. Flaky red bark on younger trees, characteristic reddish-brown plates with surface scales on older trees Leaves in fascicles of 2, long, dark yellow-green. Reportedly break clean when bent (when fresh) Seed cones long with rounded, chestnut-brown apophysis. Umbo is unarmed. Not serotinous. Pinus sylvestris Scots pine The most widely distributed pine in the world. Found throughout all of Eurasia from the Arctic Circle to the Meditterranean and from sea level to As expected there is lots of variation across this range. Up to 19 different morphological forms have been recognized. Leaves in fascicles of 2, long, bleu-green, stiff and sharp pointed, persistent for 2-3 years. Bark becomes gray and furrowed on lower trunk, but upper portion remains papery-scaly and is reddish-brown. Seed cones stalked, long, with raised, pyramidal apophysis and unarmed umbo often pointing back towards base of limb. Widely planted throughout North America as an ornamental, plantation species, reforestation projects, erosion control, etc. Has naturalized from the upper Midwest throughout the notrtheast. 81

6 Pinus nigra Austrian Pine Native to Eurasia, mostly more southern latitudes than P. sylvestris. Widely planted as an ornamental in N. America and has also naturalized in many areas. Tolerant of dry soils, pollution, heat and cold stress etc. 2 subspecies widely separated May reach 150 tall, 2 diameter. Bark is gray brown, furrowed into irregularly shaped scaly plates Leaves in fascicles of 2, long, stiff, dark green do not snap like Pinus resinosa. Seed cones 2-3 long, yellow-brown with keeled cone scales, umbo with deciduous prickle. Cones not serotinous and shed at maturity (not retained). 82

7 3-needled pines (mostly ) Pinus ponderosa ponderosa pine A very wide ranging species capable of occupying very diverse sites. It is very drought tolerant and shade intolerant. Dominates the driest forest communities of the Pacific slope and the inland Northwest often in pure stands ponderosa pine parkland. But will also occur serally in association with Pseudotsuga menziesii, Abies grandis, and Pinus contorta all more shade tolerant than Pinus ponderosa. Dominate species on the driest sites it occupies in the central and southern Rockies, but like in the inland NW, occurs serially with more shade tolerant species (Pseudotsuga menziessii, Pinus contorta, and Abies concolor) on the more mesic sites. Is found mostly in mixed stands on the eastslope (dry side) of the Sierras. As with most of our species with such wide geographic ranges lots of morphological variation and some geographic patterns associated with morphology. Previously 3 recognized varieties. var. ponderosa occurs from sea level to 7500 ft on the Pacific slope, Sierras, and westslope of the northern Rockies including the Columbia plateau. 97% of leaves in this region will be 3/fascicle and retain leaves for 2-3 years. Needles are long (5-10 inches) and twigs are not glaucous. var. scopulorum occurs from ft on the eastslope of the northern Rockies and throughout the central Rockies. ca. 70% of leaves in this region will be in fascicles of 2(!) rest in 3s and retain leaves for 5-7 years. Fascicles of 2 and 3 on same tree. Needles are short (relatively 3 to 7 inches), twigs glaucous, cones smaller. var. arizonica occurs from in the southern Rockies from southern Utah and Colorado through Mexico. Leaves are mostly in fascicles of 4 or 5! Fascicles of 4 and 5 on same tree. Needles are short (relatively 3 to 7 inches), twigs glaucous, cones smaller environmental?? Now 4 recognized subsp. - NOT ARIZONICA (now recognized as Pinus arizonica subsp. ponderosa - the 'North Plateau' group - British Columbia, western Montana, Idaho, and Washington, Oregon, California & Nevada east of the Cascades crest (red); subsp. benthamiana - the 'Pacific' group - Sierra Nevada and west of the Cascade crest in California, Oregon and Washington (green); subsp. brachyptera - the 'South Rockies' group -Arizona and New Mexico (pink); subsp. scopulorum - eastslope of the northern Rockies and throughout the central Rockies - Montana, Dakotas, Wyoming, Utah, E Nevada, Colorado, Nebraska, Oklahoma (cyan). 83

8 Leaves long in fascicles of 3 (subsp. ponderosa and subsp. benthamiana), shorter in fascicles of 3 (subsp. brachyptera); shorter in fascicles of 2 and 3 (subsp. scopulorum) Seed cones 2-6 long borne on a very short stalk, scales with a yellow-brown transversely keeled apophysis, umbo armed with slender prickle (not incurved) Is this an example of genetic isolation by geography, or environmental variation? How to test? On the best sites (west side of Cascades in OR, west side of Siskiyous and Sierras tall and 3-4 in diameter. Bark is black, rough and furrowed on younger trees, but eventually becomes yellowreddish brown with irregularly shaped scaly plates and fissures on older trees. Leaves are gray-green to yellow-green (a lot dependant on variety), long in fascicles of 3 (var ponderosa), shorter in fascicles of 2 and 3 (var scopulorum), or shorter in fascicles of 4 and 5 (var arizonica). Seed cones are 2-6 long borne on a very short stalk. Opening and shedding at maturity. Scales with a yellow-brown transversely keeled apophysis, umbo armed with slender prickle var. scopulorum has a stouter prickle Evolved with frequent low-intensity fires which are critical to maintain and promote healthy stands. The most important timber producing pine large stands in every state west of the great plains. The second most important timber producing tree in N. America what was the first? Pinus jeffreyi Jeffrey pine Occupies slopes in the Siskyous and Sierras from Often associated with Pinus ponderosa (reportedly hybridize where ranges overlap), Pseudotsuga menziessii. Very similar to Pinus ponderosa, ecologically and morphologically, but can tolerate more extreme temperatures (high and low) and greater evaporative demands than Pinus ponderosa tall and 3-5 in diameter at maturity on favorable sites Bark composed of scaly, irregularly shaped plates diided by fissures and is cinnamon-red to purple on mature trees. Leaves are blue-green with stomatal lines (note differences inthis characteristic as compared to P. ponderosa) on all surfaces fascicles of 3 Seed cones are 5-10 long, yellow-brown to red-brown. Scales with a thickened apophysis, transversely keeled, umbo armed with stout, incurved prickle (curved back towards cone axis [not so in Pinus ponderosa) 84

9 Pinus coulteri Coulter pine Occupies mountain slopes of the southern California coast and Baja California, Mexico from 3500 to 7000 elevation (typically, but occasional in the foothill chaparral when fire excluded!). Shade intolerant and grows slowly tall and diameter. bark dark gray, composed of scaly ridges divided by deep furrows Leaves in fascicles of 3, 6-12 long, gray-green, rigid, sharp-pointed with stomatal bands on all sides. Persistent 3-4 years. Seed cones 8-14 long, yellow-brown, persistent for several years. Cone scales thickened, 4-sided and keeled above (less so, and below), apophysis rhomboidal and terminates in very stout, flattened sharp claw. Seeds with very hard coat and long wing ie, seed shorter than wing. Look for this character in the scar left by the seed and wing on the upper surface of scale. The heaviest cone of any conifer 4-6 lbs when green. Hybridizes with Pinus jeffreyi where overlap Pinus sabiniana foothills pine (gray pine) Occupies seasonally dry foothills and mountain slopes of the California coast ranges and the west slope of the Sierras from elevation (very occasionally up to 6,000 ). Occurs in pure, park-like stands and in association with several oak species tall and 1-2 diameter at maturity Typically forking trunk with open branching and an irregularly shaped, round topped corwn. Bark is light grayand smooth on younger trees but scaly, firrowed and red-brown on older trees Leaves in fascicles of 3, 6-13 long, gray-green, many stoamatal bands, flexible, persistant 3-4 years Seed cones 6-10 long, yellow-brown, persistent for several years. Cone scales thickened, 4-sided and keeled above (less so, and below), apophysis rhomboidal, terminating in stout, flattened, sharp claw Seeds with hard coat and short wing ie, seed longer than wing. Look for this character in the scar left by the seed and wing on the upper surface of scale. Fire intolerant Native Americans harvested seeds and the sweet inner bark of the roots. 85

10 Did not get to these in lecture, but here are the notes so you have them for your information Pinus radiata Monterrey pine Narrow endemic to the central coastal California fog belt. Found naturally only in 3 small populations in central CA coast and 2 islands off the coast of Baja California Mexico. No commercial value in native range, but Interestingly, the most widely planted species outside of its range. Plantations established in New Zealand, Australia, South Africa, and South America. Over 1.5 million acres! Fast growing species in plantations and appears to be hardy up to the Puget Sound. In native range tall and 1-3 in diameter. In cultivation, tall and 30 in diameter within 30 years! Leaves fascicles of 3 (sometimes 2), 4-6 long, slender, flexible, and dark green. Persisting 3-4 years. Seed cones long, asymmetrical and serotinous 86

11 subg. Pinus: the southeastern Pines Pinus palustris longleaf pine Occupies a diversity of habitats from well-drained, sandy soils to seasonally flooded hard pan to dry ridges in the southeastern US. Often forms pure stands. It is estimated that less than 3% of the native longleaf pine forest remains of the once 90 million acres that existed before colonization. Fire suppression, agriculture and logging are all leading sources of deforestation of this community. Seedlings go through grass stage tree does not establish annual growth rings, but grows intermittently when conditions permit so a dense bunch of needles is all that appears on the soil surface often mistaken for a bunch grass. Typically first 3-6 years, but sometimes as many as 20 years! These seedlings establish well-developed root systems and are fire resistant tall and in diameter Bark is black and rough on young trees but is divided into large reddish plates on mature trees Leaves in fascicles of 3, 8-18 long, bright green, with a long fascicle sheath up to 1.5 long. Fascicles crowded on the ends of stout branches leaves persistent for 2 years. Cones 6-10 long, sessile (or nearly so) usually leaving behind a couple of scales when shed, apophysis reddish brown weathering gray, wrinkled, umbo armed with prickle that curves towards the base of the scale Mature Pinus palustris forests are one of the most species rich forests outside of the tropics, home to numerous endemic plants and animals. Hybridizes with Pinus taeda! P. sondereggeri Pinus taeda loblolly pine Occupies moist, poorly drained soils typical of the coastal plains and river bottoms of the southeastern US, but can be found in drier sites inland where it will hybridize with Pinus palustris as well as numerous other southern pines (e.g., P. elliotii)! Occurs in pure stands as well as mixed with hardwoods hickories and oaks, as well as other pines. It is more shade tolerant than Pinus taeda or P. elliotii, but less so than the hardwood associates. Aggressively establishes itself in pure stands on abandoned agricultural fields very fast growing seedlings in the open (popular plantation tree) may gain 3 in height and ½ or 87

12 more in diameter per year for first 10 years. 25 year old trees may be 70 tall and 1 growth rings are possible. Over 2 billion seedlings planted throughout the south every year. Important for industry as well as reforestation on degraded sites. Lots of pest that attack monoculture plantations, but breeding programs have been successful in developing disease/pest resistant and fastgrowing genotypes tall, feet in diameter - bark is black and scaly on young trees, but later develops into irregularly shaped brown plates weathering reddish brown. Leaves in fascicles of long yellow-green and persistent for 3 years. Seed cones long, sessile, scales with a flattened apophysis, wirinkled, umbo armed with stout, sharp prickle Pinus elliottii slash pine Occupies sandy soils on low-lying sites with abundant moisture in the SE more restricted range and habitat than P. palustris or P. taeda. Hybridizes with both. Very fast growing and like P. taeda it will aggressively establish on cutover land and/or abandoned fields. Rapid growth of this species and high quality wood have led to widespread plantations even in sub-tropical regions such as Brazil. It is more shade tolerant than P. palustris and less so than P. taeda. Variety densa in south FL also has grass-stage tall and 2 in diameter Bark is deeply furrowed on young trees and plated with thin, papery purple layers to 1 thick on mature trees Leaves 6-9 long, fascicles of 2 and 3, dark, glossy green, persistent for 2 years Seed cones long, persistent for 1 year, stalked. Apophysis lustrous and usually rounded, umbo armed with sharp prickle 88

13 Pinus echinata shortleaf pine Occupies diverse sites of the southeastern US but most commonly found in upland sites in pure stands or in association with P. taeda, P. virginiana, Junperus virginiana. Like most of the southern pines, early seedling development is rapid may reach 60 and 8 diameter in 35 years tall and 2-3 diameter Bark is black, rough and scaly on young trees,reddish-brown with irregular plates on older trees Leaves in fascicles of 2 and 3, 3-4 long, dark, glossy green, slender and flexible persistent 3-5 years Seed cones long with reddish-brown rounded apophysis, umbo armed with small, sometimes deciduous prickle Pinus taeda is usually on moister sites, but where it is found with P. echinata (where ranges overlap and on drier sites) Pinus taeda will have smaller cones and shorter leaves and is sometimes hard to distinguish. Hybridizes with most other southern pines. Pinus rigida pitch pine Occupies diverse sites of the northeastern US/Appalachains from sea level (north) to 4500 ft (southern appalachains). From mt. slopes and ridges to river valleys and swamps. Commonly small tree in northern part of range growing on poor, acidic soils e.g., Jersey Pine Barrens. Although tolerant of poor sites, best growth on well-drained soils with ample moisture tall and 2-3 diameter Bark is black, rough and scaly on young trees,reddish-brown with irregular plates on older trees Leaves in fascicles of 3, long, yellow green to green stiff, twisted Seed cones 2-4 long, apophysis slightly raised, rhombic, with strong transverse keels, reddish-brown; umbo central, low-triangular, with slender, downcurved prickle Pinus rigida originally harvested for pitch moved on to Pinus palustris and Pinus elliottii both more resoinous. Hybridizes with most other southern pines where ranges overlap... 89