Wednesday, Week 11 Announcements: Vegetative and Reproductive morphology terminology for angiosperms today – lots of terms!

Short quiz next Wednesday on Vegetative Morphology terminology!

LECTURE: Vegetative and Reproductive Morphology

Plant Morphology - form or structure of a and its parts

Vegetative morphology - any portion of a plant that is involved in growth, development, photosynthesis, support, etc., but NOT involved with sexual reproduction. Example: roots, stems, leaves, seeds, etc.

Stems At the tip of the growing shoot is a terminal bud or apical bud. A bud has bud scales surrounding it to protect the developing parts inside. Inside a bud are leaf primordia, lateral bud primordia, and the apical meristem. The apical meristem is responsible for new terminal growth.

Below the terminal bud regions of the stem may be identified as follows: node - point of attachment of a leaf lateral bud - always found in the axil of a leaf (between the leaf and stem, upward on the stem from the point of attachment of the leaf) internode - region of the stem between two nodes. OTHER STEM FEATURES lenticel – raised corky area on stem pith – the spongy central tissue in some stems leaf scar – bundle scar –

Leaves At the point of attachment of the stem to the leaf there sometimes is a small leaf-like structure attached to the stem called a stipule – a pair of appendages at the base of the leaf, occasionally fused, sometimes falling off soon after leaf develops. Stipules (presence/absence) is often diagnostic.

Leaf structure: blade - the broad part of the leaf petiole - the slender part of the leaf that attaches the blade to the stem margin - the edge of the blade; may be smooth or variously shaped (show shapes and briefly go over) ribs - vascular bundles or veins in the leaf; the central one is the midrib

75 Venation (arrangement of veins) - net veined - a branching, divergent and often reticulate pattern may be palmate or pinnate - parallel veined - primary veins all parallel as in grass

Leaf Shape: simple - undivided blade compound - blade divided into leaflets, each resembling a leaf; a leaf may be compound more than once. You can tell a compound leaf from a simple leaf, by looking for an axilary bud at the point of attachment of each blade. If you find one, the leaves are simple, if not, they are compound (there should be one at the base of the compound unit, however). dissected, or divided - blade lobed, but not all the way to the midrib. pinnate - arranged like “pinnae” on a feather palmate - arranged like fingers radiating from the ‘palm’ of your hand Leaves may be pinnately of palmately compound, however when there are three leaflets it may be impossible to tell which. In that case the leaves are called ternate.

Leaf Arrangement (attachment of leaves to stem) Alternate – one leaf per node Opposite – two leaves per node on opposite side of stem Whorled – more than two leaves per node

76 Reproductive morphology - any portion of a plant that is involved with or a direct product of sexual reproduction Example: flowers, fruits, seeds, etc.

Angiosperms (“clothed seed” ) are characterized by the presence of flowers and, more specifically, the presence of a structure called a carpel which encloses the seed

Flowers consist of a series of parts that are either all modified leaves or some are modified leaves and some are modified stems (the fertile parts).

Goethe (1749-1832)- first suggested that flower parts are modified from leaves.

Flower Parts Pedicel – modified stem leading to the flower Receptacle - end of stem on which flower is borne sepals - outer (lower) whorl of parts; often greenish - function to protect, photosynthesize, attract pollinators calyx - collective term for sepals of one flower petals - second whorl of parts; often colorful - function to attract pollinators, but often missing in wind-pollinated plants corolla - collective term for petals of one flower

Perianth – collective term for calyx and petals Flower symmetry - Radial, regular, actinomorphic symmetry - many planes of symmetry bilateral, irregular, zygomorphic symmetry - one plane of symmetry stamens - pollen producing structures - provide ‘male’ function in reproduction (pollen = male, or micro-gametophyte; sperm are produced here) consist of long filament supporting the anther, where pollen is produced androecium - collective term for ‘male’ portion of flower carpel - ovule producing structures (ovules contain the megagametophyte; eggs are produced here) consists of swollen ovary at base, elongate style supporting the stigma at the tip, where pollen is deposited - provides ‘female’ function in reproduction gynoecium - collective term for ‘female’ portion of flower (may be one or many pistils)

77 Friday, week 11 – finish up the last of the … 3-needled pines (mostly…)

Pinus ponderosa – ponderosa

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 .

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 3500-10000 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 7000 – 8000’ in the southern Rockies from southern Utah and Colorado through . 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 - and (pink); subsp. scopulorum - eastslope of the northern Rockies and throughout the central Rockies - Montana, Dakotas, Wyoming, Utah, E Nevada, Colorado, Nebraska, Oklahoma (cyan).

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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 – 150’- 180’ tall and 3-4’ in diameter. • Bark is black, rough and furrowed on younger trees, but eventually becomes yellow- reddish 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 6000’-9000’. 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.

• 90’100’ 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)

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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.

• 40’-50’ tall and 15-30” 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 – 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 1000-3000’ elevation (very occasionally up to 6,000’).

Occurs in pure, park-like stands and in association with several oak species.

• 40-50’ 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.

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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 – 50-100’ tall and 1-3’ in diameter. In cultivation, 100-140’ 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 3.5-5.5” long, asymmetrical and serotinous

81 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.

• 80’-100’ tall and 2-2.5’ 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 à P. sondereggeri http://www.youtube.com/watch?v=NYo3r-qNdXo

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

82 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 fast- growing genotypes.

• 90’-110’ tall, 2-2.5 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 3 – 4-9” long yellow-green and persistent for 3 years. • Seed cones 2.5”-6” 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.

• 60-100’ 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 2.5-7” long, persistent for 1 year, stalked. Apophysis lustrous and usually rounded, umbo armed with sharp prickle

83 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.

• 80-100’ 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 1.5” – 2” 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.

• 50-60’ 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, 2.5”-5” 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...

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