Plant ID Books and Websites

🌻 Shinners and Mahler’s Illustrated Flora of North Central Texas pdfs can be found on the BRIT website: https://www.brit.org/brit-press/nctexasflora. (Thanks to @rymcdaniel for the tip.)

🌻 Central Texas Wetland Plants: http://www.austintexas.gov/watershed_protection/publications/document.cfm?id=203088

🌻 wildflower.org. Lady Bird Johnson Wildflower Center

🌻 Wildflowers of Texas (A Timber Press Field Guide) by Michael Eason

🌻 Studies on the Vascular Plants of Williamson County, Texas: Dr. Art Gibson, a retired professor from UCLA now living in Georgetown, has an ongoing project aimed at providing field-based descriptions of the native and naturalized plant species of Williamson County: https://w3.biosci.utexas.edu/prc/K12/pdf/

🌻 Wildflower Identification Website, Search for wildflowers by location, color, shape and time: https://wildflowersearch.org/. (This website has links to a variety of sites for descriptions of each species.)

🌻 https://www.flickr.com/photos/162482904@N06/. Michael Eason's TexasFlora Flickr feed.

🌻 The Biota of North America: http://BONAP.net

🌻 Wildflowers of Texas web site by a guy named Jay. Don't know their creds, but it has lots of photos and can be easily verified: http://www.wildflowersoftexas.com/

🌻 David Bogler's Interactive Key to the Legumes of Texas:
https://davidbogler.com/Legumes/TexasLegumes.html

🌻 David Bogler's Interactive Keys by state:
📍http://davidbogler.com/MonocotsUS/MonocotFamilies.html
📍http://davidbogler.com/Grasses/GrassesUSA.html
📍http://davidbogler.com/Legumes/LegumesUSA.html

🌻 The Weedy Species of Sandmats (Euphorbia sect. Anisophyllum) in Texas : https://www.inaturalist.org/guides/2412

Becky's Identification Cheat Sheet

Trees and Shrubs

Pines

🌲 http://arnoldia.arboretum.harvard.edu/pdf/articles/1951-11--simple-key-to-the-pines.pdf

Junipers

🌲 A guide to distinguishing Texas cedar trees (Juniperus species): https://perennialecology.wordpress.com/2019/08/03/a-guide-to-distinguishing-texas-cedar-trees-juniperus-species/?fbclid=IwAR2qFVBUhT8kdhI97HqFJhMJm2OUIEr3w-JDYQIquZyFRbT5Ar4vDqeYVzE
🌲 Hints from @arnanthescout:

Can be hard to tell J. virginiana and J. ashei apart from the leaves... though it can be done.

This is one of the few cases where a photo of the full tree is actually very useful! Ashe Juniper tends to be more multitrunked, bushy, globe-like in shape. Eastern Red Cedar is more tree-like, usually with one trunk with the branches coming out the side.

We're the only ones to have this problem because (fortunately or unfortunately) the Austin metro area is right at the intersection of these two species.

Trees and shrubs with once-compound leaves

🌿 Tree-of-Heaven (Ailanthus altissima): leaves alternate, pinnately compound, 1 -3 feet long. Leaflets 11-41, 2-6 inches long, pointed at the tip with a slight hook, with glandular teeth near the base. Fruit is an oblong twisted samara, seed in the middle, hanging in dense clusters.
🌿Kentucky coffeetree (Gymnocladus dioicus): not found in Texas or other deep south states. (Someone used this as an ID in Central Texas.
🌿Black walnut (Juglans nigra): Leaves alternate, pinnately compound, 12 to 24 inches long with 10 to 24 leaflets (poorly formed or missing terminal leaflet), leaflets are ovate-lanceolate, finely serrate, and 3 to 3 1/2 inches long. Rachis slightly fuzzy.
🌿Chinese pistache (Pistacia chinensis): Leaf: Alternate, pinnately compound, 10 to 12 inches long, 10 to 12 lanceolate to narrow ovate leaflets, entire margins, tapering pointed tips. Shiny green. Dioecious; red to green, males in tight 2 to 3 inch long clusters (like buds) along last year’s stem, females in looser, longer groups, somewhat showy since they appear before the leaves in early spring.
🌿Western Soapberry (Sapindus drummondii): Leaves alternate, pinnately compound, 8 to 13 inches long, 9 to 15 lance-shaped, inequilateral (similar to Prairie Flameleaf Sumac), pointed leaflet (less so than Prairie Sumac), each 2 to 3 inches long, yellow-green above, slightly fuzzy beneath.

From @baldeagle: “First, young soapberries have a tendency to produce leaves that are not true to form in a couple of ways:
They are odd, not even, pinnate.
In the case of S. drummondii, they have the wings that are typical of S. saponaria.

Fortunately, we have an easier way to distinguish between S. drummondii and S. saponaria: if it's west of the Mississippi, it isn't S. saponaria. Even I can remember that. :-)”
🌿Soapberry (Sapindus saponaria): We don’t have it west of the Mississippi. Our young Western Soapberries often have winged rachis.

🌿Mexican Buckeye (Ungnadia speciosa) has 3-lobed fruits similar to the buckeyes in the Horse Chestnut genus Aesculus but its leaves are pinnately compound instead of palmately compound.

Trees and shrubs with bi- and tri-pinnate compound leaves

🌿Chinaberry (Melia azedarach): Leaves alternate, single to doubly pinnately compound, 10 to 22 inches long, leaflets coarsely toothed or lobed. Long, loose cluster of purple flowers. Fruits in hanging clusters, up to 3/4 inch diameter, yellow-brown drupe. Ripen in fall, persist through winter.
🌿Goldenraintree (Koelreuteria paniculata): Leaves alternate, pinnately (or partially bi-pinnately) compound, irregular serrations or lobes on leaflets, 8 to 14 inches long, 9 to 15 leaflets, deep green above, lighter below. Bright yellow flowers, about 1/2 inch wide), in a 10-15 inch, many-branched, terminal panicle. Fruits are a triangular, papery capsule, in clusters.
🌿Nandina domestica: Upright canes instead of a trunk; leaves all come off the cane. No lateral branching. Thrice odd pinnate.

Wildflowers

🌻 Euphorbia sect Poinsettia (I forgot whose advice this was, but it's very helpful)
🌿 E. dentata: Leaves: opposite decussate and in canopy often helically alternate, simple, petiolate, with stipules; stipules 2, on swellings at base of petiole with tiny glandular tips; petiole channeled, 5−25 mm long, puberulent; blade narrowly ovate to lanceolate or narrowly lanceolate, (15−)25−65 × 12−25 mm, > petiole, tapered at base, dentate-serrate on margins, blunt-acute at tip, pinnately veined with principal veins whitish and raised on lower surface, upper surface glabrate with several hairs, lower surface evenly pubescent with scattered hairs to 0.8 mm long.

🌿E. davidii: Leaves: opposite decussate to subopposite and in canopy often helically alternate, simple, petiolate, with stipules; stipules 2, on swellings at base of petiole with tiny glandular tips; petiole channeled, 5−25 mm long, green aging rose-red, puberulent to short-hairy; blade lanceolate or narrowly lanceolate to elliptic, in range (15−)25−50 × to 14 mm, > petiole, tapered at base, crenate and often somewhat wavy on margins and sometimes partially inrolled under, obtuse to blunt at tip, pinnately veined with principal veins purple-red sunken on upper surface and at least midrib raised on lower surface, upper surface sparsely puberulent and densely short-hairy along principal veins, lower surface evenly pubescent with evenly spaced bent hairs (bases sometimes enlarged, pustulate).

🌻 Oenothera:https://www.inaturalist.org/posts/23932-notes-on-oenothera-and-list-of-the-species-of-texas

🌻 Lindheimer Senna: Extrafloral nectaries between the leaflets (all pairs), thin colored tips. White leaflet margin, hairy. Tip from @jeanphilippeb.

🌻 Small blue skullcaps:

• Scutellaria wrightii vs Scutellaria drummondii: curve upward in corolla tube and woody stems from past growth point to this perennial (from @franpfer).
• Tips from @arnanthescout: https://www.inaturalist.org/journal/arnanthescout/63318-scutellaria-drummondii-vs-scutellaria-wrightii

🌻 Central Texas frogfruits, genus Phyla, from https://warcapps.usgs.gov/PlantID/Species/Details/4050:
"Phyla nodiflora has leaf blades mostly widest toward the apex and toothed only near the apex. Phyla lanceolata has leaf blades that are mostly widest at or below the middle and toothed from below the middle to the apex (also fits P. ... Peduncle less than or slightly longer than the leaves (4-9 cm)."

🌻 Mexican Primrose-willow (Ludwigia octovalvis, a native) vs Peruvian Primrose-willow (L. peruviana, an exotic invasive): Both are yellow flowered, water-loving, bushy evening primroses with largish yellow flowers with 4 petals and 8 stamens. Fruits are 4-sided. Leaves are alternate in both.

• Leaves of L. octovalvis have a short but distinct petiole, where leaves of L. peruviana have no petiole (or just a suggestion of a petiole, if you're not really into the specifics of petiole attachment). Neither species has wings.
• L. peruviana has moderately squat fruits--about 3-4 times longer than the width at the tip--and very noticeably wider at the tip than the base. L. octovalvis fruits are elongated and thinner with less prominent widening at the tip.
• Their habitats overlap in marshy places and along streams and ponds, but L. peruviana can apparently handle less water and may grow in ditches and other places not actually near the edge of or in water.

Primrose-willow ID info:

• Texas: https://aquaplant.tamu.edu/plant-identification/alphabetical-index/water-primrose/
• Florida, with many of the same species, with a diagnostic diagram: https://plants.ifas.ufl.edu/site/assets/files/2615/ludwigiaidguide.pdf

🌻 Small blue sages:

Salvia texana: "Upper corolla lip shorter than in S. engelmanii and not pilose on the upper surface. Also, this corolla is slightly more blue than the pale lavender you generally see in S. engelmannii." (From @alex_abair)

🌻 Triodanis, Venus’s Looking Glass
From @suz:

• Triodanis Species ID Chart, Venus’s Looking Glass flowers:
  https://drive.google.com/file/d/1G1pro3tLp9Lp_9dFrjo9pBGTf0xhte_2/view

• Triodanis Quick Tips: https://www.inaturalist.org/journal/kimberlietx/51636

🌻 Monarda, Beebalms and Bergamots (https://www.inaturalist.org/observations/84118325)
M. citriodora has showier flowers than M. punctata. Both have multiple tiers of flowers.
🌿M. punctata (Spotted Horse Mint):

• Bracts underneath the circle of flowers are white with pink/rosy tips.
• Bracts extend much farther out than the flowers.
• Flowers are yellow with spots. (smaller than M. citriodora)

🌿M. citriodora (Lemon Beebalm, Horsemint):

• Bracts underneath the circle of flowers are purple.
• The flowers extend almost as far out as the bracts.
• Flowers are shades of purple/pink/white with spots. (larger than M. punctata)

🌿M. fistulosa (Wild Bergamot) has a single ring of flowers with no bracts above the flowers.

🌻 Ruellias:
Ruellia nudiflora (Violet Ruellia) vs Ruellia drummondiana (Drummond's Ruellia)

Info from iNat user @baldeagle (https://www.inaturalist.org/observations/24971861): "... Although R. nudiflora is found in some places in Walnut Creek Park, this particular plant is another species. That species is endemic to a relatively small area including Travis County."

"... note the broadly elliptical leaves with acute apices. That's one way to differentiate this species from R. nudiflora. Even though each species can thrive under either condition, R. nudiflora tends to be found in full sun and R. drummondiana tends to be found in full shade."

🌻 Gutierrezia texana vs Amphiachyris species in North Central Texas, by @rymcdaniel: https://www.inaturalist.org/journal/rymcdaniel/28366-differentiation-of-gutierrezia-texana-and-amphiachyris-species-in-north-central-texas

🌻 That plant from Llano County with small silver leaves that looks like Silver Ponyfoot but the leaf petiole isn't quite right (tapers from leaf, not a sharp connection): Eriogonum tenellum var. ramosissimum, https://www.inaturalist.org/taxa/240663-Eriogonum-tenellum-ramosissimum

🌻 Argemone, Prickly Poppies:

• From @ncowey: https://www.inaturalist.org/observations/44209042

• From @ronstephens:
  @jbecky see discussion at:
https://www.inaturalist.org/observations/112312965
from my notes:
Latex (sap)
pale yellow - White Prickly Poppy (Argemone albiflora) Petals white
bright yellow - Mexican Prickly Poppy (Argemone mexicana) Petals yellow
pale yellow - Thistle Poppy (Argemone polyanthemos) Petals White - all leaves very glaucous, thick and leathery
reddish orange - Texas Pricklypoppy (Argemone aurantiaca) Petals white or lavender
white: pale yellow of Argemone albiflora


• I forgot who gave me this tip (if it was you, please contact me for credit): "Argemone aurantiaca (Texas Pricklypoppy):
  The prickles on the capsules appear to be branched. Those are unbranched on A. albiflora."

• How to Identify Anemones in TX, by @pfau_tarleton : https://docs.google.com/presentation/d/1llZApbJ29F2h9w7EYA7D3B-cDAcQra0GC01zWMCvVc8/edit#slide=id.p

🌻 Identification of Milkweeds in Texas (by TPWD and Baylor U): https://tpwd.texas.gov/publications/pwdpubs/media/pwd_rp_w7000_1803.pdf

🌻 Zephyranthes rain lilies:
📍https://www.backyardnature.net/n/h/rainlil2.htm
📍Z. drummondii: You can see the anthers in the flower tube, but they don't stick out. You can't see the stigma. Also tends to be larger.
📍Z. chlorosolen: The anthers stick out of the flower tube. You can see the stigma, which is capitate (like a head or balled up fist). Generally smaller.
➡️ From @joshua_tx: "In the first photo, to the right of your hand about even with the top of your knuckles there is a visible joint on the stem. Above this joint is a slightly pinkish papery sheath around the stem. This joint marks the transition from stem to flower, meaning everything above this point is flower. You can see that makes for a reallyyy long flower! Both species show some natural variation as to floral tube length but Z. drummondii is never going to be that long. Z. drummondii can sometimes appear to have long flowers if the flowers happen to sit atop long stems but if you look for that joint you won't be fooled. The anthers either being protruding outside the floral tube in Z. chlorosolen or retracted inside the floral tube in Z. drummondii is probably the best single clue to species. Z. drummondii also has wider, usually blue-green leaves that more or less trail along the ground while Z. chlorosolen has narrower, greener leaves that are held more erect. Z. drummondii blooms primarily in the Spring but also blooms in smaller numbers through Fall while Z. chlorosolen blooms primarily in late Summer/early Fall and is not common to find it blooming out of season in the Spring." — https://www.inaturalist.org/observations/59656594

🌻 Yellow Passionflower vs. Bracted Passionflower: "The easiest way to distinguish these two are the filaments - lutea can be wavy, affinis can be straight - but look at the end of the filaments - affinis will be clavate at the tip (club shaped), where lutea will not" — From Texas Flora Facebook Page

🌻 Mimosas: We have half a dozen similar native Mimosa species across Texas but most have stem prickles and are called Sensitive briars and the flower heads all appear as pink "puffs" like this. M. strigillosa has only hairs instead of prickles. Mimosa pudica is an introduced species which has escaped in a few SE coastal states, Florida, Virginia and Maryland. It is sold by biological supply houses for classroom demonstration of the leaf sensitive feature. It is the number one plant misidentification because of its prominence in Google. Supposedly native to South and Central America but introduced elsewhere in Asia. — Floyd Waller, Texas Flora Facebook page,

🌻 Smilax: Smilax tamnoides (Bristly Greenbriar) has dark, needle-thin prickles. Fruits don't have the waxy coating of many other Smilax. S. bona-nox (Saw Greenbriar) has tricolored prickles (green on the wider bottom, narrowing to a point through brown and yellow).

🌻 Agalinis, False Foxgloves: https://www.inaturalist.org/journal/pfau_tarleton/27184

🌻 Erodium of Texas (from https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=25041):

Posted on October 21, 2019 05:19 AM by jbecky