Plant Taxonomy and Field Identification
The universal language of plants — from scientific names to field identification
Chapter 9: Field Guides, Herbaria, and Digital Tools
Why this matters: Your tools determine your accuracy. Knowing which resources to trust, how herbaria work, and how to use digital tools correctly makes the difference between confident identification and dangerous guessing.
9.1 Evaluating Field Guides
NOT ALL FIELD GUIDES ARE EQUAL:
CRITERIA for a good field guide:
1. REGIONAL SCOPE
A guide covering "North America" is less useful
than one covering Texas specifically
More species = less detail per species
2. SCIENTIFIC NAMES included
Any guide without scientific names = limited value
Common names change by location
3. PHOTOS vs ILLUSTRATIONS
Photos: realistic, show actual variation
Illustrations: show idealized features clearly
Both have value — best guides have both
4. FRUIT AND SEED PHOTOS
Most guides show flowers but not fruit
Fruit photos greatly aid year-round ID
5. SIMILAR SPECIES section
Good guides explicitly address lookalikes
Critical for safety
6. AUTHOR CREDENTIALS
Botanist, naturalist, or experienced field person?
Or just a nature enthusiast?
Check credentials for medicinal/foraging guides
FOR TEXAS — RECOMMENDED GUIDES:
Wildflowers:
Geyata Ajilvsgi — "Wildflowers of Texas" (revised edition)
Best all-around Texas wildflower guide
Good photos, reliable ID, covers common species
Claude Barr — "Jewels of the Plains"
Central prairie wildflowers
Trees:
"Trees of Texas" — Paul Cox & Patty Leslie
"National Audubon Field Guide to Trees:
Western Region" — covers Texas trees
Grasses:
"Grasses of the Texas Hill Country" — B.L. Turner
"Grasses of the Great Plains" — Barkworth et al.
Technical (for serious botanists):
"Flora of North Central Texas" — Diggs, Lipscomb, O'Kennon
Best regional technical flora available
Keys, descriptions, excellent illustrations
"Manual of the Vascular Plants of Texas" — Correll & Johnston
Comprehensive, dated (1970) but still valuable
Foraging:
"Foraging Texas" — Delena Tull
Written by Texas botanist, reliable, safety-conscious
⚠️ CAUTION with general foraging guides:
Guides written for Northeast, Pacific Northwest, etc.
may not distinguish Texas species correctly
Always verify against Texas-specific resources9.2 How Herbaria Work
HERBARIUM: a collection of preserved plant specimens
From: 9.2 How Herbaria Work
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9.3 Digital Tools for Plant Identification
iNATURALIST (inaturalist.org)
From: 9.3 Digital Tools for Plant Identification
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1. iNaturalist is a citizen science platform that can help identify plants
2. A hand lens (10x) is useful for examining small floral structures
3. A photo showing only the flower is usually sufficient for plant ID
4. iNaturalist identifications are always correct
5. The USDA PLANTS database is a free online resource for plant information
6. Herbarium specimens are pressed dried plants used for scientific reference
7. The Lady Bird Johnson Wildflower Center database focuses on Texas native plants
8. Digital apps completely replace the need for traditional field guides
9. Pressing plants preserves them for long-term study
10. GPS coordinates add scientific value to plant observations
11. A botanical illustration shows more diagnostic detail than a photograph
12. All field guides cover all plant species in a region
13. Taking multiple photos from different angles improves ID accuracy
14. Voucher specimens are pressed plants with collection data for scientific reference
15. PlantNet and iNaturalist use AI for plant identification
16. Texas A&M AgriLife Extension provides free online weed and plant resources
17. Smell is not a useful field characteristic for plant identification
18. The season affects which identification features are available
19. Joining a native plant society can improve field ID skills through mentorship
20. A field guide written for another region can be used reliably for Texas
1. Name five reliable free online resources for Texas plant identification.
2. What photographs should you take to document an unknown plant for identification?
3. What is a herbarium and why are herbarium records scientifically valuable?
4. What are the limitations of smartphone plant identification apps?
5. How should you prepare a plant press for preserving specimens?
6. What is the USDA PLANTS database and what information does it provide?
7. What field equipment should a beginning plant identifier carry?
8. Describe the best practice for noting field observations when finding an unknown plant.
9. What is iNaturalist and how does the community identification system work?
10. How does joining a plant society improve field identification skills?
1. The free citizen science platform using AI and community identification is .
2. Pressed dried plant specimens preserved for scientific reference are called specimens.
3. The USDA database providing species information, distribution maps, and photos is PLANTS.
4. A magnifying glass providing 10-power magnification used in the field is called a lens.
5. The university in College Station with a major Texas plant extension resource is .
6. A plant pressed with collection data (date, location, habitat, collector) is called a specimen.
7. The native plant database hosted in Austin focused on Texas and adjacent states is .
8. Field guides organized by color are easiest for beginners to use.
9. The process of making a permanent record of a plant by pressing and drying it is called .
Complete in the field. Check each off as you go.
1. Field Documentation Practice: Find 5 unknown plants. Photograph each: whole plant, leaf (upper/lower), stem cross-section, flower if present, fruit if present, habitat. Submit to iNaturalist.
2. Build a Plant Press: Construct a simple plant press from two plywood boards, absorbent paper, and straps. Press 10 plants. Note: plants should be flattened while fresh.
3. Resource Comparison: Look up the same plant species in 3 different resources (USDA PLANTS, LBJWC native plant database, and a regional flora). Compare the information quality and type.
4. Join iNaturalist: Create an account, submit 10 plant observations from your property with photos. Review the community IDs you receive. Assess their accuracy.
5. Native Plant Society Field Trip: Research your local native plant society chapter (NPSOT). Attend one field trip or meeting. Field trips with experts are the fastest way to improve identification skills.
Chapter Summary
BEST TEXAS RESOURCES
From: Chapter Summary
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Next Chapter → Building a Personal Plant Journal
Connections to Other Topics
→ C02 Ch05: Dichotomous Keys — using these tools with published keys
From: Connections to Other Topics
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