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Week 8, Monday Announcements: Last labs of Pinaceae / conifers this week – ca. 66 species total! Abies – True Firs Abies is well-represented in temperate forests of the northern hemisphere, including North

America, Mexico, and Central America, Europe, Asia, and Northern Africa. Typically in moist sites. It has been a taxonomically problematic group where numerous species hybridize and create extensive hybrid zones and this has createdmany problems – even to the point of defining species boundaries in Abies.

Latest treatment recognizes 39 species worldwide and 9 species in North America. There has been very little phylogenetic work done in the genus, and so little is known about the

evolutionary relationships – currently, organized into groups based on morphological similarity only – this is a project ripe for the picking…

Latest phylogenetic study (Xiang et al. 2004) leaves a lot to be desired…OVERHEAD Abies species growing in southern latitudes are typically restricted to the upper slopes of

mountains and are commonly found near treeline. In the Boreal zone, Abies species are largely restricted to lower elevation forests.

General features of the genus. Leaves: Sessile, linear, spirally arranged, but may appear 2-ranked or strongly upswept due to

twisting at the base of the leaf. Leaf morphology often varies dramatically from the shade to the crown – crown leaves often more glaucescent and shorter, shade leaves often greener, longer, and more “2-ranked” – WHY?

Twigs: Large, smooth, circular leaf scars. Buds generally rounded (Note exception!), 3 at apex – 1 terminal and two opposite lateral buds – leads to a very regular, opposite branching pattern.

Cones: Erect cones, scales and bracts are deciduous at maturity, leave behind conspicuous spike-like axis that often persists throughout the winter.

The character of having erect, deciduous cones was thought of as a derived character in Pinaceae to group Abies with several other genera in Pinaceae that have this character (including Cedrus, Pseudoliarix). Given this phylogeny (Wang et al. 2000) what do you think? OVERHEAD

ANSWER: this trait likely evolved in parallel in these different genera, given that Cedrus, Abies,

and Pseudolarix, are not each other’s closest relatives (i.e., they don’t form a monophyletic group).

Identification of species depends on a couple of key characters, including morphology of the

leaves (arrangement/attachment, stomata on 1 or both surfaces, having a ridge or grove on the upper surface of the leaves, etc.) and the morphology of the bracts of mature seed

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cones. Bracts are apiculate and often shouldered - the length of the bract, apiculate tip with respect to the shoulders, whether the bract is exsterted or not, are all identifying characteristics.

Abies lasiocarpa – subalpine fir The most widespread of the western North American firs. Range includes the Rockies from the

Yukon to southern Arizona as well as the Cascade and Coast ranges of Oregon and Washington – not found in California.

Dominant species of the subalpine zone – often found in association with Picea engelmannii.

Around here you will find both of these species growing together in “frost-pockets” and inversion zones at lower elevations.

• 60-100’ tall, 1-2’ diameter, characteristic “spire-like” shape of most Abies • bark is smooth and gray with resin blisters, becoming slightly furrowed on very old trees • leaves ¾” – 1” long, upswept arrangement, 2 stomatal bands above and one above. • Ovuliferous cones 2-3” long, purple at maturity, bracts are not visible in intact cone

and have a characteristic long, apiculate tip – shaped like the tree, spire –like Because of widespread nature of the species there is a lot of variation – sp much so, that is was recently separated into two species in the treatment for the Flora of North America. 1. Abies bifolia – Rocky mountains – very slight differences in the color of the leaf scars (tan) and the shape/margins (isosceles triangles/entire) of the basal-most bud scales (!) 2. Abies lasiocarpa – Cascades and Coast range, leaf scars red, basal most bud scales are

equilateral triangles and margins are toothed. These characteristics are not necessarily consistent and there is a ton of variation, so we will

continue to treat these as one species – A. lasiocarpa. Subalpine fir is not used commercially; harvest in this delicate ecosystem is discouraged. Balsam wooly adlegid (Adelges picea) is a European insect similar to an aphid that was

introduced to NAm ca. 1900. Feeds by inserting mouth parts into the inner bark of true firs. Destroys buds/shoot apices and eventually kills the tree. Abies lasiocarpa is particularly susceptible – a 1998 survey estimated 125,000 acres of infestation in northern and central Idaho.

Abies balsamea – balsam fir Closely related to A. lasiocarpa, occupies the spruce-fir zone of the boreal and northern

deciduous forests with Picae glauca and Picea mariana. It is the dominant Abies species of eastern North America.

• 40-60’ tall, 12-18” diameter, probably the most symmetrical, pyramidal crown of any of

the eastern/boreal conifers – spire-like

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• very similar to A. lasiocarpa in terms of morphology, however, upper surface of leaves have a much reduced or absent stomatal band so green above, gray below

• cones typically smaller than A. lasiocarpa – 1.5-3” – but this is not very satisfying Like most of the Picea species that occupy these same ranges, Abies balsamea will hybridize

with A. lasiocarpa where their ranges overlap at the northern edge of the A. lasiocarpa range and the southern edge of the A. balsamea range.

Major source of pulpwood in Canada, popular Christmas tree. Highly susceptible to the balsam wooly adelgid. Abies fraseri – fraser fir Closely related to A. balsamea – occurs only in the high mountains of southern Appalachains in

VA, NC, GA, but only in isolated populations. Future for natural populations highly uncertain – range nearly decimated by balsam wooly adelgid.

• 30-50’ tall, 10-15” diameter • very similar vegetatively to A. balsamea • cones typically 1.5-3” – with exserted bract and strongly reflexed

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Week 8, Wednesday Announcements: Last lab of Pinaceae / conifers this week – ca. 65 species total! Lab next Monday will be all review, Wednesday is the gymnosperm lab practical covering all of our gymnosperm species – no lecture next Wednesday. Next Friday is the second hourly exam – review session on Tuesday the 6th from 2:30-3:30 No campus walk Friday – Monday? Ended talking about A. fraseri – ALLOPATRIC vs. PARAPATRIC SPECIATION Abies grandis – grand fir Our familiar Northwest mesic forest disjunct distribution – found in the Cascades and the

northern Rocky mountains. Generally a low elevation seral species on the Pacific coast. In the northern Rockies, it is seral with Thuja plicata and Tsuga heterophylla, but dominant further south and on drier sites in the north.

• 140-160’ tall, 2-4’ in diameter. • Bark gray to brown and plated on mature trees, very solid, not corky – inner bark

(periderm) red • Leaves 1-1.5” long, 2-ranked, stomata on lower surface only grooved and lustrous

above, 2 stomatal bands below, apical notch • Cones 3-4” long, green, bracts with higher shoulders and shorter apiculate tip than

A. lasiocarpa – shoulders +/- equal height as the tip Indian paint fungus causes large trees to be rotten in the center – consequently, not commercially

viable for lumber (same thing happens to A. balsamea). Abies concolor – concolor fir Divided into two varieties, var. lowiana found at low to mid elevation in the Sierras and var.

concolor occupying dy sites from mid-high elevation in the central to southern Rockies. Both varieties have numerous geographically isolated small populations that exhibit a lot of morphological variation – not a very consistent species! In the Flora of North America treated as 2 distcint species.

• 90-150’ tall, 1-4’ in diameter. var. conclor is typically smaller, occupies drier sites, so it

makes some sense, no? • Bark gray to balack on mature trees, thick and corky – inner bark (periderm) yellow • Leaves typically longer (variable), uniformly glaucous, no groove, no apical notch

(var. concolor) – grooved and notched (or not) and with a stomatal band above or uniformly glaucous (var. lowiana) – obscurely 2-ranked, typically upswept.

• Cones 4-5” long, green, bracts with higher shoulders and shorter apiculate tip than A. lasiocarpa – shoulders +/- equal height as the tip

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Abies concolor and A. grandis are two very closely related species and may represent a recently

diverging species – these two species intergrade extensivelyto form a nearly continuous hybrid species complex from southwestern Oregon to central Idaho. The resulting pattern is one of highly variable morphological intermediacy that has completely confounded taxonomic efforts to understand the evolution of these two species. Thus, the delimitation of species in these areas is a large source of contention – Todd Ott (UI grad student) is studying this problem in detail and is trying to sort it out! Good luck!

Abies amabilis – Pacific silver fir Occupies low to upper elevation forests of the Cascades, Olympics, BC Coast ranges and fog

belt. Grows with Thuja plicata and Tsuga heterophylla at lower elevation and has similar tolerances in terms of moisture requirements. At higher elevations, often found with A. lasiocarpa, Picea engelmannii, and Tsuga mertensiana.

• 140-160’ tall, 2-4’ diameter. Spire-like sahpe. • bark smooth and gray • about 1” long, lustrous green above, 2 stomatal bands below, sometimes notched, more or

less 2-ranked in appearacnce, but with a row of leaves along the top of the twig, pointed forward and often appressed to the stem.

• Seed cones purple, 3-6” long, bracts with long apiculate tip and no shoulders Has also been affected by balsam wooly adelgid. Discussion of hybrid origin, sympatric speciation etc. Abies procera – noble fir Occupies upper mid-elevation forests of the west slope of the Cascades.

• 150-200’ tall and 3-5’ diameter • Bark gray – reddish brown, start smooth, but becomes plated with age • Leaves .5-1” long, upswept arrangement, 2 stomatal bands on both surfaces, narrow

groove on upper surface of leaf, shaped like hockey sticks • Seed cones brown to purple, 4-7” long, bracts exserted and reflexed to the point where

they cover the scales. Prized Christmas tree – wood is considered to be the best of the genus. Abies magnifica – California red fir Occupies mid elevation to subalpine forests of the Sierra Nevada and extreme southern

Cascades. Closely related to A. procera

• 150-180’ tall, 4-5’ in diameter – largest of all Abies • bark plated and reddish brown

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• Leaves very similar (almost indistinguishable) to Abies procera, but with small ridge on upper surface (grooved in A. procera)

• Cones purple to brown, 6-9” long, bracts +/- as long as scales – mostly inserted. Forms extensive hybrid swarms with A. procera in the northern Sierras and southern Cascades.

The hybrid intermediates have been designated as a distict species, A. shastensis – another outstanding question…

Abies bracteata – bristlecone fir This is the rarest of all firs and in the few phylogenetic studies is resolved as the sistergroup to the rest of the genus. Occupies the dry forest of the Santa Lucia mountains in the Coast range of central California in Monterey county between 2000 and 5000’ – lots of endemics in this area!

• Small to medium sized tree, 40-100’ tall and up to 3’ in diameter. • Leaves 1.5-2 ¼ inches long, stiff and sharp-pointed, +/- 2-ranked, green above with

ridge, stomatal bands below • Buds, ovoid, pointed, and ¾-1” long • Seed cones 3-4” long with spiny, long-exserted and strongly reflexed bracts with a

very long bristle

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Week 8, Wednesday Announcements: Lab next Monday will be all review, Wednesday is the gymnosperm lab practical covering all of our gymnosperm species – no lecture next Wednesday. Next Friday is the second hourly exam – review session on Tuesday time and place to be announced Lecture: Pinus: Pines Includes ca. 100 spp. widely distributed throughout forests of the northern hemisphere from the

northern limits of tree growth in North America and Eurasia, to N. Africa, Mediterranean, Malaysia and Sumatra (one population of Pinus merkusii gets just south of equator).

Mexico is the center of diversity with 43 spp. ca. 37 species native to US – 15 eastern US, rest

western US. Most important timber producing genus of all conifers. Also important sources of pulp wood,

turpentine, pitch, wood tars , etc. Several species produce edible seeds – pine nuts. Very important ecologically. Major component of boreal, sub-alpine, temperate, and tropical dry

forests, as well as arid woodlands. Vegetative features: Produce 2 types of leaves – 1. Primary leaves – solitary, spirally arranged, non-photosynthetic, often deciduous or drying

within a few weeks of their appearance, and 2. Secondary leaves, acicular, fascicled, borne on determinate short shoots in the axils of primary

leaves. Fascicles consist of usually from 2-5 leaves, but can be as few as 1 and as many as 8 (rare). Basal sheath deciduous or persistent, composed of 6-12 bud scales. Secondary leaves persistent for 2 to several years (or up to 20!).

Reproductive features: Monoecious; woody seed cones are lateral or sub-terminal with spirally arranged bracts and

scales, scales with 2 ovules on upper surface. Take 2-3 years to mature. Scale apophysis has an armed or unarmed umbo. Classification: Separated into two subgenera – subg. Pinus and subg. Strobus – hard and soft pines,

respectively.

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Subgenus Primary leaves

fascicle sheath

Needles/fascicle Cone scales

wood

Strobus Deciduous; smooth twigs

Deciduous early

5 (1) – needles; 1 vascular bundle

Usually thin – mostly unarmed

Soft, transition from early to late wood gradual

Pinus Persistent; rough twigs

Persistent, falling with fascicle

2-3 (rarely 5-8); 2 vascular bundles

Usually thick, mostly armed with prickle

Hard, transition from early to late wood abrupt

NOTE: the number of needles/fascicle is variable! Explanation of early wood / late wood - Growth rings are formed because the part nearest the

center of the tree is usually composed of wider xylem elements. It is almost invariably lighter in color than that near the outer portion of the ring.

The inner portion is formed early in the season, when growth is comparatively rapid; it is known as early wood or spring wood.

The outer portion is the late wood or summer wood, being produced in the summer. In subg. Strobus there is not much contrast in the different parts of the ring, and as a result the

wood is very uniform in texture and is easy to work. In subg. Pinus, on the other hand, the late wood is very dense and is deep-colored, presenting a

very decided contrast to the soft, straw-colored early wood.

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Pinus monticola – western white pine Occupies forests with ample moisture on the Pacific slope and Sierras and disjunct in the

northern Rockies. Typically a montane species, but does occur at sea-level on the Olympic Peninsula and British Columbia coast.

Intermediate in shade tolerance – with Thuja plicata, Tsuga heterophylla, Abies grandis, Larix

occidentalis in north and at higher elevations in Sierras with Calocedrus decurrens and Sequoiadendron.

• 170-180’ tall, 2-4’ in diameter • bark smooth and gray on young trees, forms plates/fissures on old trees to 1.5’ thick – not

fire resistant • deep, wide spreading root system • leaves persistent 3-4 years, glaucous, blue-green, stomatal lines on inner surfaces. • Seed cones 4-10” long, cone scales thin, somewhat reflexed, umbo unarmed, tan

apophysis with slightly pointed apex. Seed wings about ½” shorter than scales (this is 1/4'” in P. strobus)

Severely impacted by white pine blister rust – fungus introduces to N. Am. From Eurasia in early

1900’s. Breeding programs to produce resistant strains have been somewhat successful. WPBR affects all 5-needled pines.

Pinus strobus – eastern white pine Occupies northern deciduous zone – occurs (or used to anyway) in mostly pure stands on

moderately moist soils.

• 80-100’ tall, 2-3.5’ diameter • Leaves glaucous, blue-green, fascicles of 5 – very similar vegetatively to P. monticola • Seed cones 3-8” long cone scales are thin and not reflexed, umbos unarmed with tan

apophysis with rounded apex. Seed wings about ¼ ” shorter than scales (this is 1/2” in P. monticola)

Largest of the northeastern conifers and thus, heavily logged throughout range. It is now used

extensively to establish new plantations in NE US. Not sister species with P. monticola! Historically used for ship masts – one of the primary sources of friction between the colonies and

the crown. More resistant to white pine blister rust than P. monticola, but still a problem.

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Pinus lambertiana – sugar pine Occupies sites from 1100’-5400’ in the southern Cascades and northern Sierras and from 2000-

7800’ in central and southern Sierra Nevada. Very rarely found in pure stands. This is the largest of all pines – discovered by David Douglas. Very fast growing – 2nd only to Sequoiadendron in the Sierra Nevada – 100 year old tree may be 140’ tall and 3’ in diameter – may live 500-750 years.

• 170 to 180’, 2-4’ diameter – largest is >260’ and 11.5’ in diameter! • Bark reddish-brown, composed of scaly ridges separated by fissures – up to 4” thick at

maturity • Leaves glaucous, blue-green, fascicles of 5, stomata on all surfaces. Very similar to

western white pine, but needles spirally twisted. • Seed cones largest of any pine – 11” - 21”. Apophysis somewhat thickened, yellowish

brown, diamond shaped, terminal umbo unarmed, with deep seed wells. Named for sweet, sugary sap that flows from bark injuries – eaten by Native Americans Pinus flexilis – limber pine Occupies dry, rocky slopes and high ridges from the pinyon-juiper zone of the southwestern US

all the way to timberline throughout the Rocky mountains. Frequently forms pure stands along the east slope of the northern Rockies and much of the Great Basin, and east slope of the Sierra Nevada.

Named for very flexible branches that can be tied in knots.

• Smaller tree – 40-50’ tall and 2-3’ in diameter on good sites, but often more shrub-like,

twisted and contorted at high elevation. May live >1500 years. • Bark dark brown and composed of superficially scaly, rectangular plates separated by

fissures on mature trees – light gray and smooth on young trees. • Leaves yellowish-green and stout – 2-3.5” long – in fascicles of 5, faint stomatal bands.

Clumped near tips of branches – leaves retained up to 6 years. • Seed cones 3-6” long with raised, gold colored apophysis and terminal umbo. Seeds with

rudimentary wings or unwinged – deep seed wells with no wing scar. Seeds distributed by wildlife – especially Clark’s nutcracker – cache seeds and forget where they

all are, so get clumps of individuals together. Ecologically important for controlling soil erosion. OR public broadcasting video of oldest Pinus flexilis in Wallowas – http://www.opb.org/programs/ofg/segments/view/1739

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Week 8, Friday Announcements: No campus walk today – see where I get, but maybe Monday second ½ of class. Lab next Monday will be all review, Wednesday is the gymnosperm lab practical covering all of our gymnosperm species – no lecture next Wednesday. Tuesday review session – CNR room 10, 2:30-3:30 Friday, second lecture exam. Pinus albicaulis - whitebark pine Occupies rocky soils on exposed mountain slopes and ridges in the subalpine to timberline.

Occurs in small, pure stands.

• On exposed high elevation sites it often has twisted, crooked, shrub-like form, but may reach 20-50’ tall and 1-2’ in diameter with a tree-like form at favorable sites – see ‘the snag’

• Bark, whitish gray and smooth on young trees, scaly on mature trees • Leaves yellowish-green and stout, fascicles of 5, clumped near the tips of limbs. Very

similar vegetatively to Pinus flexilis. • Seed cones 1.5-3.5” long and serotinous, with very thick cone scales, terminal umbo

armed • Seeds large, thick walled, wingless.

This alpine tree is the only North American representative of the “stone pines” – serotinous species associated with a nutcracker for seed dispersal – Clark’s nutcracker breaks cones open to get at seeds and leaves cone scales behind – forgets where all seeds are cached so get clumps of individuals together. Ecologically important for controlling soil erosion and watershed protection, similar ecological

niche as Pinus flexilis. Seeds eaten by native Americans and important food for Black and Grizzly bears. Severely impacted by whitepine blister rust – although some resistance has developed. Pinus aristata – bristlecone pine 2 varieties. Var. aristata – Rocky mountain bristlecone Occupies rocky soils on exposed mountain slopes of the subalpine zone to timberline in

Colorado, northern Arizona, and northern New Mexico

• May reach 20-40’ tall and 1-1.5’ in diameter on good sites, Appears more shrublike, twisted and stunted at higher elevations on exposed sites. May live >2500 years.

• Often gnarled with multiple trunks – some dead and bare, some alive • Leaves, blue-green, stout, blunt pointed, fascicles of 5 (mostly), stomata above, grooved

below, conspicuous white resin. Fascicles long persistent – 20 years – and arranged on stem like hair on a fox’s tail – foxtail pine.

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• Seed cones 2.5”-3.75” long, brown with slender, round-based cone scales and bristled umbos

Ecologically important for controlling soil erosion and watershed protection. Pinus aristata var. longaeva Occupies rocky soils on exposed mountain slopes of the subalpine zone to timberline in the

Great Basin and Sierra Nevada Similar vegetatively and reproductively to var. aristata

• May reach 20-40’ tall and 1-1.5’ in diameter on good sites, Appears more shrublike, twisted and stunted at higher elevations on exposed sites. May live >5000 years.

• Often gnarled with multiple trunks – some dead and bare, some alive Pinus edulis – pinyon pine Occupies dry, rocky slopes mesas and plateaus 5000’-8000’ elevation in association with

junipers and sagebrush. Defines the pinyon-juniper zone that covers about 90,000 square miles in the four corners region of the SW US.

• Short-trunked, round topped, bushy tree – 15’-35’ tall and 1-2’ diameter • Bark reddish brown, with scaly ridges separated by fissures • Leaves in facicles of 2, light green, short and stout, curved and half-circle in cross

section. • Seed cones 1.5-2” long and squatty with very thick scales, especially umbo. Large,

wingless, edible seeds. Source of pine nuts – only commercially sold “nut” producing tree that is not cultivated. Seeds extremely important food source for Native Americans and wildlife of the dry intermountain region. Pinus monophylla – singleleaf pinyon Occupies dry, rocky slopes, mesas and plateaus from 5000-8000 feet throughout the Great Basin.

Common component of the pinyon-juniper zone in the intermountain region – 65,000 acres.

• Small shrubby round-topped tree with gray-green crown, 15-30’ tall and 1-1.5’ in

diameter, • Bark is brown-gray and scaly with ridges • Leaves are solitary, round in cross section, stout, sharp pointed, and gray-green with

whitish stomatal bands • Seed cones 2-3” long, yellow-brown and very squat with thickened scales, especially

unmbo. Has deep seed wells for unwinged seeds.

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Seeds extremely important food source for Native Americans and wildlife of the dry

intermountain region. subgenus Pinus – hard pines – remind of characters separating subg. Strobus (soft) and subg.

Pinus (hard pines) Remember that leaf number per fascicle is variable – even within an individual – but it is usually a good place to start. Pinus contorta – lodgepole pine Widely distributed throughout the forests of western North America – from the Yukon to Baja CA. Occupies variable sites from sand dunes along the Pacific Coast to the subalpine zone of the Cascades, Sierra Nevada, and Rockies to 12,000’ (huge ecological amplitude). As expected for a species with such a large geographic and ecological range, there is lots of variation. General features:

• Bark 1” thick, orange-brown to gray, typically scaly, but may become plated with age. • Leaves in fascicles of 2, ¾”-3” long, yellow to dark green, persistent for 3-8 years. • Seed cones asymmetrical (but see var. murrayana) or contorted, ¾”-2.25” long with a

tan-brown umbo and prickle that may or may not be deciduous. • Seed cones mature in 2 years but remain on tree for many years. Serotiny varies with

variety. 3 recognized varieties. var. contorta – shore pine. Forms pure stands along the Pacific coast and lowlands from Alaska

to northern CA. Typically shorter and bushier than other varieties, 25-30’ tall, 12-18” diameter – first variety to be described, and people often say contorted nature of the shore pine is where the name comes from – not true – contorted seed cones. Not serotinous.

var. latifolia – lodgepole pine. The inland form found in the Rockies. 70’-100’ tall, 12-30”

diameter, and much narrower crown and straight trunk than var. contorta. Cones are often serotinous – may remain on trees up to 20 years and require temps of 45-50C to open. Adapted to take advantage of exposed mineral soils following a fire. Regen after fires in the Rockies can be very dense – 320,000 seeds per acre!

var. murryana – lodgepole pine. Cascades, Blue mountains (?), and Sierra Nevada. 80-140’

tall, 12-30” diameter. similar in stature to var. latifolia. Biggest difference is that seed cones are +/- symmetrical!

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Pinus banksiana – jack pine Occurs mostly in pure stands and mixed with birches and aspens on dry, sandy, acidic soils –

generally poor solis that can’t support Pinus strobus or Pinus resinosa (eastern red pine). On better sites, will grow with Pinus strobus and P. resinosa. Very shade intolerant, so will often be replaced by more shade tolerant species. There is considerable variation across the large geographic area that it occupies.

• 70-80’ tall, 12-15” diameter on best sites, but often stunted and scrubby on poor soils or

open habitats. • Bark is reddish-brown to dark gray, scaly and divided into ridges. • Leaves in fascicles of 2, ¾”-2” long, yellow-green, stout, concave or flat on the inner

surface – sometimes in fascicles of 3 near the leader! • Seed cones 1”-2.25” long, brown, curved with apex pointing toward limb tip.

Apophysis rounded with no or very minute prickle. Seotinous in the northern part of range, not so much in the south.

Hybridizes with closely related P. contorta where their ranges overlap in Alberta. Critical habitat for the federally listed Kirtland’s Warbler in central Michigan. http://www.youtube.com/watch?v=cpdzsvafFcs Pinus virginiana – Virginia pine

An Appalachian species occurring on variable soils, but capable of colonizing poor soils of abandoned farmland and strip mines.

• May reach 40’-70’ tall, 1’-1.5’ diameter at maturity. Retains branches. • Bark is thin and smooth on young trees, red-brown, scaly and plated on older trees. • Leaves in fascicles of 2, ¾” – 3” long, gray-green to yellow-green • Seed cones 1.25-2.75” long, light brown with reddish-brown apophysis and a prominent

prickle. Not serotinous but may remain on tree for 3-4 years. *These three species are good example of allopatric dissection of geographic space – all in same clade, similar ecologies – section Contortae – geographically separated…what kind of speciation?

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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, 4-6.25” long, dark yellow-green. Reportedly break clean when bent (when fresh)

• Seed cones 1.5-2.5” 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 8000’. As expected there is lots of variation across this range. Up to 19 different morphological forms have been recognized.

• Leaves in fascicles of 2, 1.5-3.75” 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, 1.25”-2.5” 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.

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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, 3.5”-6” 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).

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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 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 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).

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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 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 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

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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

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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

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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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Lecture: Species, Species concepts, and speciation. Basic observation: Incredible diversity of life on earth – we’ve seen this in the gymnosperm taxa that we’ve studied so far – many appear to be discrete groups (separated by ecology, genetics, etc.), Why is the world like this? How does this come about? What is a species? Classic textbook answer: Ernst Mayr (1963) – “Species are groups of actually or potentially interbreeding natural populations that are reproductively isolated from other such groups.”

Capacity for reproducing together that defines species and the inability of (or lack of opportunity) for reproduction that marks the separation between species. Captures the essence of genetic separation, but cases where this does not apply…examples? – hybrids, asexuals, etc…Many plants!

Straightforward mechanisms that actually separate things – common isolating mechanisms:

1. Premating or prezygotic – e.g., pollinators, phenology (plants); behavior, gamete release (animals)

2. Post pollination/insemination – e.g., self incompatibility/gemete recognition – mediated by enzymes/proteins/genetics

3. Post zygotic/post fertilization – e.g., viability, survival, fertility a. Much more common in plants – examples from class?

So, species can be separated by various mechanisms.,, Species concepts through time: “A species is what a competent taxonomist says it is” (quote attributed to Art Cronquist) Morphological species concept - post-Darwin

-species concept based entirely on morphology, including variation - the range of variation is measured and species boundaries are defined by gaps or

morphological discontinuities. - variation is genetic and environmental; there is no perfect ‘type’ - Numerical taxonomy is recent manifestation of this concept.

Continuing debate centers around whether species are things that exist in nature (resulting from

the process of evolution), OR whether species are arbitrary units to be defined based on consistent criteria by those who study them.

These two philosophies derive from two very different ways of viewing the relationship between nature and the role of taxonomy.

What do you think?