Plant Labs

Scientific name of the shin dagger

*Agave lechuguilla *

Scientific name of creosote bush (or greenwood or governess)

*Larrea tridentata*

Honey mesquite scientific name

*Prosopus glandulosa*

Escapism examples

- Annuals - Biennials

What makes a desert a harsh environment?

- lack of water - low humidity - temperature extremes - high winds - High soil salinity/alkaline

4 tactics

1. Escapism 2. Opportunism 3. Tolerance 4. Avoidance

What is a desert?

A dry, barren region that recieves less than ten inches of rain a year

Annuals

A flowering plant that completes its entire life cycle in a single year or growing season

Tactics employed by the creosote bush

All of them; escape, opportunism, tolerance, and avoidance

Biennials

Angiosperms that complete their life cycle in two years

What does having small leaves avoid?

Avoid water exiting the stomata (aka desiccation) by having a small surface area

*Leuchophyllum* sp./rain sage tactics

Avoidance (small leaves)

What is the indicator plant of the Great Basin desert?

Big sage brush

4 North American deserts

Chihuahuan Sonoran Mojave Great Basin

*Salsola tragus*/tumbleweed tactics

Escapism (drops seeds as it tumbles), avoidance (small leaves), and opportunism (shallow roots)

*Leuchophyllum* sp./rain sage defining characteristics

Flowers (white, pink, or purple)

*Fouquieria splendens*/ocotillo/coach whip adaptations

Green bark

Tolerance (being tough) examples

Low water and high salt in tissues

Tactics

Morphological traits to survive

*Opuntia polycantha* sp./common name: prickly pear cactus tactics

Opportunism (shallow roots

*Fouquieria splendens*/ocotillo/coach whip tactics

Opportunism (shallow roots)

*Salsola tragus*/tumbleweed defining characteristics

Purple and green lines on its stem

*Fouquieria splendens*/ocotillo/coach whip defining characteristics

Red tubular flowers, and rarely flowers and leaves and the same time

What is the indicator plant of the Sonoran desert?

Saguaro cactus

Opportunism examples

Shallow roots Deep tap roots

Cacti have ___ ___ so they can maximize water absorption. Trees and big shrubs have a(n) ___ ___ ___ so that they can reach the water table.

Shallow roots, deep tap root

Avoidance examples

Small leaves, leaflets

Defining characteristics of creosote bush

Smells like rain! Yellow flowers

*Opuntia polycantha* sp./common name: prickly pear cactus adaptations

Spines (modified leaves)

What is the indicator plant of the Chihuahuan desert?

The *Agave lechuguilla*, more commonly known as the shin dagger

What desert do we live in?

The Chihuahuan desert

What is the indicator plant of the Mojave desert?

The Joshua tree

*Baileya multiradiata*/desert marigold defining characteristics

Velvety cuticle, perennial, yellow flower

*Leuchophyllum* sp./rain sage adaptations

Velvety, thickened cuticle that maintains water

*Asclepias subverticillata*/milkweed adaptation

White secretion (protection against herbivores)

Opportunism

grabbing opportunities; seeking unprincipled advantage

*Parkinsonia aculeata*/palo verde tactics

opportunism (deep tap root) and avoidance (leaflets)

*Prosopus glandulosa*/honey mesquite tactics

opportunism (deep tap root) and avoidance (small leaves)

*Chilopsis linearis*/desert willow tactics

opportunism (deep taproot) and avoidance (thin leaves

*Yucca treculeana* sp./Torrey yucca tactics

opportunism (shallow roots)

*Prosopus glandulosa*/honey mesquite defining characteristics:

seed pods have circles, formed by beetles called weevils

*Yucca treculeana* sp./Torrey yucca adaptations

thin, fibrous leaves

*Yucca treculeana* sp./Torrey yucca defining characteristics

white, highly aromatic flowers

Parkinsonia aculeata/ palo verde defining characteristics

yellow flowers and thorns and green bark