Family, Genus, Species…What? Plant Identification
Scott Oneto & James Sigala
June 02, 2011 UC Master Gardener Conference, Santa Rosa The World of Plants
321,212 recognized plant species in 462 different families! The most diverse families of flowering plants, are:
• Asteraceae (sunflower family): 23,600 species • Orchidaceae (orchid family): 22,075 species • Fabaceae (pea family): 19,400 • Rubiaceae (madder family): 13,150 • Poaceae (grass family): 10,035 • Lamiaceae (mint family): 7,173 • Euphorbiaceae (spurge family): 5,735 • Melastomataceae (melastome family): 5,005 • Myrtaceae (myrtle family): 4,620 • Apocynaceae (dogbane family): 4,555 Steps to Plant Identification
Determine the type of Plant Steps to Plant Identification
1. Determine gross morphology? • Annual, biennial, perennial • Woody, herbaceous • Deciduous or evergreen Steps to Plant Identification
2. Determine: monocot or dicot Steps to Plant Identification
3. Identify the anatomical features of the leaves • Composition: Simple vs Compound • Arrangement: Alternate, Opposite, Whorled • Shape • Margin • Tip/Base Steps to Plant Identification
4. Identify the anatomical features flowers/fruit • Flower parts: calyx, corolla • Male parts • Female parts • Ovary position • Flower symmetry • Type of Inflorescence • Fruit type Asteraceae
• dandelion, chrysanthemum, yarrow, coreopsis, sunflower, dahlia, zinnia, goldenrod,
fleabane, aster, sneezeweed, groundsel, ageratum, thistle, cosmos , and Black-eyed Susan Asteraceae
• leaves are alternate, opposite, or whorled • simple to pinnately or palmately compound • four to five stamens Asteraceae
• Capitulum • Florets may be perfect, imperfect • Ovary is inferior
Ray floret Disc floret Asteraceae
• Heads composed of only ray flowers , as in dandelion, endive , and wild lettuce . • Heads composed of only disk flowers , as in ageratum, thistles . • Heads composed of both disk and ray flowers , with disk flowers tightly packed together in the head's "eye," while enlarged ray flowers function as petals radiating outward from the eye . Species in this group include sunflowers, asters, Black-eyed Susans, chrysanthemums, dahlias , zinnia Ray floret Disc floret Asteraceae
• Modified leaves = bracts • Bracts can be side to side or overlapping • Collection of bracts = involucre
Key Asteraceae Characteristics
• Involucre • Capitulum, with tens to hundreds of florets (ray and/or disc) Apiaceae
• Carrot, parsley, anise, dill, hemlock… Apiaceae
• Often hollow stems
• The leaves are mostly alternate and pinnately or palmately compound leaves. Clump at base • Some have aromatic foliage Apiaceae • Small flowers in umbels, short flower stalks (pedicels), spread from a common point. • 5 sepals, 5 petals and 5 stamens. • White, yellow or pink flowers • Inferior ovary
Key Apiaceae Characteristics
• Mainly have hollow stems • Small flowers in umbels • Flowers with five petals, five sepals, five stamens • White, yellow or pink flowers Malvaceae
• Hibiscus, okra, cotton Malvaceae
• Kapok, cheese weed… Malvaceae Key Malvaceae Characteristics
• Alternate leaves, palmate, usually veined • Five-lobed calyx, five fused petals forming a tube. • Many stamens fused into a tube surrounding the pistil. • Superior ovary Fabaceae
• Legume or Pea Family • Behind the Orchids and Sunflowers, the pea family is the third largest. – 18,000 species in 630 genera
Fabaceae
• Leaves range from pinnately or palmately compound to simple • Leaves are alternate, stipulate, and have a pulvinus • Ovary is superior and the fruit is usually a legume • Pea shaped flowers: 5 petals • 10 stamens
Erythrina crista-galli Lamiaceae
• Mint Family • 3500 species in 180 genera • Known for its spices; Oregano ( Origanum vulgare ), spearmint ( Mentha spicata ), peppermint ( Mentha piperita ) basil ( Clinopodium vulgaris ) and lavender (Lavandula angustifolia ) Lamiaceae
• Leaves are simple • Opposite leaf arrangement • Square stems • Flowers parts in 5's • Petals fused (2 up, 3 down) • 5 united sepals • Four stamens (2 long, 2 short) • Usually aromatic
Plant Identification Unknown Sample #1
Online Resources
• Oregon State Woody Plant Identification http://oregonstate.edu/dept/ldplants/plant_ident
Unknown Sample #2 Online Resources
• The Encyclopedia of Houseplants http://www.gflora.com
Plant Family? New Age of Plant Identification
Digital Field Guides Eliminate the Guesswork Apps for iPhones, iPods, iPads
• TreeBook: guide to 100 of the most common trees in North America • Leafsnap: developed by Columbia University, the University of Maryland, and the Smithsonian Institution, uses visual recognition software to help identify tree species from photographs of their leaves.