OBE Seminar today12:10 Skaggs 117

Eric Aschehoug (PhD Defense)

“Indirect Interactions and Plant Community Structure”

Christina McBane & Hilary BlandBlue Mountain

More Asteridae - big families!

Asteraceae Apiaceae

Apiaceae - Carrot family Inflorescence

umbel (often compound)

Apiaceae - Carrot family Special Fruit type

schizocarp = 2 fused achenes

Lomatium - Biscuitroot - herbs w/ ferny leaves

- common in rocky grasslands

- flowers often yellow

- taproot edible (with processing)

Asteraceae - Aster or Composite familyAlternate name: Compositae

Distributionworldwide, primarily temperate zoneextremely diverse: 1500 genera, >23,000 species

Asteraceae - Aster or Composite family

Each “flower” is an inflorescence

Inflorescence = a head with involucral bracts

Asteraceae - Aster or Composite familyInflorescence = a head with involucral bracts

Asteraceae - Aster or Composite family2 kinds of flowers in composite heads

-- disk flowers (radially symmetric, in center)-- ray flowers (irregular, often sterile)

Inflorescencereceptacle

Involucralbracts

Asteraceae - Aster or Composite family

Asteraceae - Aster or Composite family

Inflorescencereceptacle

Asteraceae - Aster or Composite family

Inflorescencereceptacle

Asteraceae - Aster or Composite family3 kinds of inflorescences

ray flowers only disk and ray flowers disk flowers only

Not all composites are yellow -- this is just a sample!!

Asteraceae - Aster or Composite familyFruit type = acheneoften with pappus (calyx) modified for wind dispersal

Asteraceae - Aster or Composite familyIn Montana

largest family: 80 genera, 374 speciesmostly herbs, some shrubs (ex. Artemisia or Sagebrush)several Noxious Weeds (ex. Centaurea or Knapweed)

Asteraceae - Aster or Composite familyLeaves

alternate or oppositeentire, toothed or pinnately lobedsometimes prickly (thistles)often a basal rosette in perennial herbs

Aster - Aster - >25 species in Montana

- annual or perennial herbs

- leaves simple, often linear

- disk and ray flowers

Centaurea - Knapweed/Star-thistle - ~5 non-native weeds

- perennial herbs w/ taproot

- leaves simple, lobed, compound

- plants spiny

Artemesia - Sagebrush - 20 species

- dryland shrubs

- leaves simple or lobed; hairy

- plants aromatic

- disk flowers only (not showy)

Boraginaceae

Lamiaceae

Scrophulariaceae

Solanaceae Phlox

Campanula

Dodecatheon

More Asteridae - big families!

Asteraceae Apiaceae

Exam 2 grade distribution

Mean = 80Median = 81