Diario de sedgequeen

The program "Letters to a Pre-Scientist" has expanded and needs about 1000 more volunteers than it has. Volunteers are involved with STEM fields (science, technology engineering and math). Each is paired with a student in 5th grade through high school. Volunteer and student exchange 8 letters (4 each) over the school year. Are you interested? Sign up fast! Registration will close within a week.

E-mail I received about this:

For the first time ever, we’re reopening STEM pen pal recruitment because, at this time, we do not have enough STEM professionals to pair with all the students we’ve committed to working with this year!

We’re thrilled to have over 3,700 students on 47 teachers’ rosters approved by their schools to get paired with a STEM pen pal for the 2023-24 school year. Right now, we only have 2,879 STEM professionals who are eligible to be matched!

That means we’re looking for close to 1,000 MORE pen pals to make sure each student gets to correspond with their very own STEM professional this year.

If you missed the first deadline to register, you get another chance! Hooray!

And – the program is already starting! Just today we matched the first 500 students with pen pals. Over the course of September, we’ll continue working to get volunteers registered and trained, and supporting teachers and students to get ready to be matched.

So, I'm reaching out to you today to see if you are interested in becoming a pen pal this year, and to ask if you could share the opportunity with your friends and colleagues and encourage them to sign up! Head to https://prescientist.org/volunteers/ to find out about the program and register!

Please see the information below for FAQs.

FYI, we only plan to keep this second round of recruitment open for one week to make sure we can stick to the deadlines we’ve set with our teachers and get through the entire program this year. We'll send information about the mandatory training by mid September.

Thanks for helping us recruit more volunteers!

With gratitude,

Lucy Madden
CEO, Pre-Scientist, Inc

Prickly poppies have leaves like some thistles and allies, but they're very different plants in the Poppy Family (Papaveraceae). They have white to orange sap. Flowers have 6 petals arranged in 2 whorls.

Basically, there are two species of Argemone introduced to Africa (but see notes at the end). They are pantropical weeds. They're easy to tell apart in flower and sometimes the non-flowering rosettes can be distinguished, though there is over lap. This photo has both species of Argemone (as well as some other plant): https://www.inaturalist.org/observations/146463972

Argemone mexicana -- Petals yellow. Leaves and lobes broader, often. Present in east Africa and in Benin.

Argemone ochroleuca -- Petals white to pale yellow. Leaves and lobes narrower, the leaves therefore seeming more prickly. Present in east Africa but not, at this point, in Benin.

There are two odd observations from South Africa. They seem to have very white petals, more petals than expected, and more open inflorescence. A third species? Something in cultivation? Just odd members of one of the above? The two observations I have seen are https://www.inaturalist.org/observations/148441411 and https://www.inaturalist.org/observations/151186362

ECHINOPS

This annotated checklist started to help guide my identifications of Echinops. Then I realized they present too big and diverse a problem for me. I offer it to you.

Although I hope the list is complete, it may not be -- use caution. Corrections welcome.
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Echinops of EAST AFRICA

Echinops aberdaricus -- POWO: The native range of this species is Kenya to Tanzania. No iNaturalist observations. Heads large. Leaves 3-4 pinnate, the lobes narrow, moderately to very narrow. Secondary lobes crowded near base of primary lobes, generally longest less than half as long as primary lobe. Lower leaf surface white. No iNaturalist observations.

Echinops acaulus -- POWO: an unplaced name.

Echinops amplexicaulus -- POWO: The native range of this species is Nigeria to Ethiopia and Tanzania. Flowers red (unique in the genus?). Leaves broad with shallow lobes. 8 iNaturalist observations.

Echinops angustilobus -- POWO: The native range of this species is Ethiopia to Kenya. -- Flowers white. Leaves tripinnate, the lobes narrow and long, terminal lobes longer than the others. Blade tissue along midrib narrow, and leaflets are narrower. Secondary lobes not crowded at base of primary. Undersurface of leaf white. 1 iNaturalist observation.

Echinops eryngiifolia -- POWO: The native range of this species is E. Central & E. Tropical Africa. -- Leaves narrow, unlobed, long, tapered gradually to a spine tip. Leaf margins with stout antrorse hairs (or small spines). Lower side of leaves maybe glaucous. Head maybe surrounded by leaves, but that may be just the way specimens are pressed. One head oval - typical?? No iNaturalist observations.

Echinops giganteus -- POWO: The native range of this species is Nigeria to Ethiopia and Tanzania. -- However, it’s also in Cameroon. Or something called that is in Cameroon. Flowers usually white, apparently sometimes blue. Petals long and thin. Plants tall, much branched, with deeply lobed leaves, typical thistle leaves. Turns out that leaf shape is highly variable. In Ethiopia, leaves are often deeply divided. Elsewhere, and sometimes there, leaves are much less divided, sometimes almost toothed rather than lobed. 3 iNaturalist observations.

Echinops hispidus -- POWO: The native range of this species is Eritrea to Tanzania. -- A flat thistle (i.e., acaulous). One big, sessile, spherical head, with spines. Leaves bipinnate, white-hairy on both sides, lobes narrow, linear, and if there are spines on the margins they’re remote and small -- or maybe spines at tips and on short lobes at base of secondary lobes. 2 iNaturalist observations that may or may not be the same species as the POWO specimen photo.

Echinops hoehnelii -- POWO: The native range of this species is Ethiopia to E. Central & E. Tropical Africa. It grows primarily in the montane tropical biome. -- Flowers white. Leaves typical of thistles. 5 iNaturalist observations.

Echinops hussonii -- POWO: The native range of this species is Sudan, Arabian Peninsula. -- Flowers white. Leaves with basic thistle shape but a little wide, with the lobes few but wide, the longest one about midlength on leaf, so the leaf is elliptical or diamond-shaped in outline. Leaves pale below, probably white. No iNaturalist observations.

Echinops kebericho -- POWO: The native range of this species is Ethiopia. -- Flowers white. Plant big, much-branched. Leaves may have a relatively linear blade around the midrib, then moderately short lobes. 2(3) pinnate. Leaves dark green above, white below. 1 iNaturalist observation.

Echinops lanatus -- POWO: The native range of this species is Cameroon, E. Tropical Africa. Flowers described as creamy brown and light green. Leaves with center of blade and primary lobes a bit wider than in many other thistles, but not unusual. Leaves green above but with whitish hairs, especially proximally, white below. Stem conspicuously white -- hairy? No iNaturalist observations.

Echinops longifolius -- POWO: The native range of this species is W. Tropical Africa to Ethiopia and Tanzania. Flowers white in most photos, deep blue in one. (Is the blue one correct?) This one has long, narrow, linear leaves like E. himantophyllus, but the leaves are a bit wider and they have distinct spiny edges, so they look serrate. 9 iNaturalist observations.

Echinops longisetus -- POWO: The native range of this species is Ethiopia. -- Tall plant, often growing like a small tree, probably >6 feet at times, often with just one main trunk and the inflorescence branched at the top, but apparently it can branch more. Leaves lobed about half way to base -- broader than many thistles. Flowers pink or white. 10 iNaturalist observations.

Echinops macrochaetus -- POWO: The native range of this species is S. Sinai, NE. Tropical Africa. -- Includes Ethiopia. Flowers white. Some photos show long spines in the heads and others lack them. Leaves on the long-spined end of thistle-like. Plants sometimes much branched, like small shrubs. 22 iNaturalist observations, all from Ethiopia.

Echinops pappii -- POWO: The native range of this species is Tropical Africa, SW Arabian Peninsula. -- Leaves green above, hairy with dense white to gray hairs below. No iNaturalist observations.

Echinops reticulatus -- POWO: The native range of this species is Tropical Africa, SW. Arabian Peninsula. -- Leaves lanceolate, unlobed, serrate. No iNaturalist observations.
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Echinops of WEST AFRICA

Echinops bampsianus -- POWO: The native range of this species is DR Congo. No iNaturalist observations.

Echinops gracilis -- POWO: The native range of this species is Guinea, Nigeria to Uganda. It grows primarily in the seasonally dry tropical biome. -- Flowers white. Leaves many and short, with short lobes (looking unlobed). Heads small and globose. Unusual for Echinops. Compare to E. himantophyllus and E. longifolius. 4 iNaturalist observations.

Echinops giganteus -- POWO: The native range of this species is Nigeria to Ethiopia and Tanzania. -- However, it’s also in Cameroon. Or something called that is in Cameroon. Flowers usually white, apparently sometimes blue. Petals long and thin. Heads appear spineless early on, but have short spines when older. Plants tall, much branched. Leaves can be deeply lobed leaves, but they may be almost unlobed In Ethiopia, leaves are often deeply divided. Elsewhere, and sometimes there, leaves are much less divided, sometimes almost toothed rather than lobed. Leaves white below. 3 iNaturalist observations.

Echinops guineensis -- POWO: The native range of this species is Guinea to Ivory Coast, Cameroon. -- Very like E. gracilis. Heads maybe a big bigger but they may not be spherical. No iNaturalist observations.

Echinops himantophyllus -- POWO: The native range of this species is Nigeria, Cameroon, Chad. -- Leaves linear, long, with short teeth or spines on margins, that are +/- remote. Leavse look more serrate than those of E. gracilis. Head +/- spherical. See E. longifolius. No iNaturalist observations.

Echinops lanatus -- POWO: The native range of this species is Cameroon, E. Tropical Africa. No iNaturalist observations.

Echinops longifolius -- POWO: The native range of this species is W. Tropical Africa to Ethiopia and Tanzania. Flowers white in most photos, deep blue in one. (Is the blue one correct?) This one has long, narrow, linear leaves like E. himantophyllus, but the leaves are a bit wider and they have distinct spiny edges, so they look serrate. 9 iNaturalist observations.

Echinops mildbraedii -- POWO: The native range of this species is Nigeria to Central African Republic. -- Leaves lanceolate, serrate, not lobed.

Echinops pappii -- POWO: The native range of this species is Tropical Africa, SW. Arabian Peninsula. -- No iNaturalist observations.

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Echinops of NORTH AFRICA

Echinops bovei -- POWO: The native range of this species is N. Africa to Sahara. (= Morocco to Libya) -- Flowers blue. Leaves deeply divided. See E. spinosissimus. One way to tell them apart: In E. bovei, the lower leaves are almost flat, usually without large spines pointing upwards above the leaf plane. In E. spinosissima s.l., the lower leaves have numerous large spines pointing upwards above the leaf plane. 27 iNaturalist observations.

Echinops buhaitensis -- POWO: The native range of this species is Ethiopia. -- Endemic to Ethiopia. The 4 GBIF records, all herbarium specimens, suggest this is a short plant (less than 17 inches tall) with crowded typical thistle leaves and a large head. No iNaturalist observations.

Echinops cyrenaicus -- POWO: The native range of this species is Libya. -- 1 GBIF record, no iNaturalist records.

Echinops ellenbeckii -- POWO: The native range of this species is Ethiopia. -- Endemic to Ethiopia. Heads large, not spiny until fruiting. Leaves divided into numerous slender, unlobed, grass-like segments. Distinctive. Plants can be large, even tree-like. 2 iNaturalist observations.

Echinops fontqueri -- POWO: The native range of this species is Morocco. -- Part of the E. spinosissimus complex. 3 iNaturalist records.

Echinops galalensis -- POWO: The native range of this species is Libya to Arabian Peninsula. -- Flowers white. Inflorescence with long spines, like E. spinosissimus. (Included in the complex??) Leaves deeply divided (more than half way to midrib) but lateral lobes short. Leaf spines long. No iNaturalist observations.

Echinops glaberrimus -- POWO: The native range of this species is E. Medit. -- Map includes Egypt, but probably it’s just in Sinai. Flowers white or pale blue. Head may or may not look spiny at flowering, but can at other stages. Leaves deeply divided, but lateral leaflets broad and tertiary leaflets if present small. Spines long. Part of the E. spinosissimus complex. 25 iNaturalist observations.

Echinops spinosissimus -- POWO: The native range of this species is E. Medit. to W. Iran and Arabian Peninsula. It is a perennial and grows primarily in the temperate biome. -- Map shows it all across northern Africa from Mauritania to Egypt. Also, Chad and Cameroon. Flowers blue or white. Head often with long stout spines, but not always. Leaves with blade tissue fairly narrow. Therefore, primary lobes appear separated. Often (but not always!) with white on midrib of leaf and lobes. Lower surface white. Many, many iNaturalist specimens. See E. chinops spinosisimum complex.

Echinops spinosissimus COMPLEX = E. spinosissimus, E. bovei, E. echinatus, E. fontqueri, E. glaberrimus. Note that E. echinatus grows in Asia, mainly India, and not in Africa. Head with long, stout spines.

Echinops strigosus -- POWO: The native range of this species is W. Medit. -- This includes N Africa from Morocco to Tunisia. Leaves pinnate and secondary lobes few. Leaves thick, green, textured, with spreading probably harsh hairs, with spines confined to lobe tips (including tips of small lobes in axils of primary lobes), and fairly short. Globe often somewhat flattened, usually seeming to be lobed because it has larger, more distinct heads than do most Echinops. A head may contain more than one flower, maybe. Many iNaturalist observations but only one from Africa.

Echinops taeckholmianus -- POWO: The native range of this species is N. Egypt. No iNaturalist observations. 3 GBIF records but none with photos.

Tragus, the Carrot-seed Grasses or Bur Grasses.

I feel I should point out that “Burr” is the surname of Aaron Burr, the U.S. vice president famous for dueling with and killing Alexander Hamilton, the former secretary of the treasury. It is not a plant part. A fruit with hooked spines is a bur.

Bur Grass leaves are relatively short and broad. Margins strongly ciliate, the cilia longer proximally. The flowering culms are much longer than the leaves. The spiny, bur-like part is the upper glume, which is usually longer than the single floret. (Lower glume reduced or absent.) What may look like a carrot seed (schizocarp) with two halves (mericarps) is actually a pair of spikelets very close together, their spiny glumes on the outside of the pair. The number of rows of spines = the number of veins. It is best assessed from the inside surface of the glume, but of course you can never see that in iNaturalist photos.

The genus has 7 species, 5 of them known from Africa.

Tragus berteronianus. Occurs in South Africa. Annual. Spine tips hooked. Longitudinal spine rows/glume: 5. Panicle branch length (0.5)0.7-2.7 mm. Spikelets/branch 2 (rarely 3). Bur shape: shorter, rounder. Range in Africa: widespread.

Tragus koelerioides. Occurs in South Africa. Perennial. Spine tips straight. Longitudinal spine rows/glume 7? Spikelets/ branch 3? Range in Africa: southern Africa.

Tragus racemosus. Occurs in South Africa. Annual. Spine tips hooked. Longitudinal spine rows/glume: 5. Panicle branch length (0.5)0.7-2.7 mm. Spikelets/branch 2 (rarely 3). Bur shape: longer, narrower. Range in Africa: widespread
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Tragus heptaneuron. Occurs in Africa but not in South Africa. Annual. Spine tip hooked. Longitudinal spine rows/glume: (5)6-7. Panicle branches 3-3.5 mm (slightly longer than the others). Spikelets/ branch 2 (rarely 3). Range in Africa: Somalia to Tanzania

Tragus mongolorum. Occurs in Africa but not in South Africa. Annual. Spine tip hooked. Range in Africa: Ethiopia to Kenya, Madagascar.

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Tragus australianus. Does not occur in Africa, as far as is known. Native to Australia. Introduced to Argentina and U.S.A. (North Carolina). Annual. Spine tip hooked. Longitudinal spine rows/glume 5. Panicle branches 0.7-1.2 mm.

Tragus andicola. Does not occur in Africa. Native to NW Argentina. Annual. That's all I know about it. Looks like 5 rows of spines, which are sharply hooked at the tip. Panicle branches short. Unlikely to show up in Africa.

A compilation of keys and descriptions for these two confusing, introduced thistles. The discussion from the FNA description of C. tenuiflorus is especially useful.

Note: POWO doesn't show Carduus pycnocephalus as occurring in most of Africa (just in north Africa and Ethiopia). However, some iNaturalist photos definitely show that species, in my opinion.

Good photo of C. pycnocephalus: https://www.inaturalist.org/observations/171379901
Good photo of C. tenuiflorus: https://www.inaturalist.org/observations/168445279

Key from FNA:
1' Heads 1–5 at ends of branches; phyllaries not scarious-margined, ± persistently tomentose, distally scabrous on margins and faces Carduus pycnocephalus
1'' Heads 5–20 at ends of branches; phyllaries scarious-margined, glabrous or sparingly tomentose, distally ciliolate or glabrous Carduus tenuiflorus

Key from Stace

2' Capitula in clusters of 3-10; stems with spiny wings right up to base of capitula; phyllaries thin and transparent on margins, without strongly thickened midrib except sometimes near apex C. tenuiflorus
2'' Capitula in clusters of 1-3; stems with discontinuous spiny wings, with at least some peduncles unwinged distally; phyllaries with strongly thickend margins and midrib for at least distal half C. pycnocephalus

Key from Flora of Oregon
1' Phyllary margins not membranous; pappus bristles 15-20 mm C. pycnocephalus
1'' Phyllary margins membranous; pappus bristles 10-15 mm C. tenuiflorus

Jepson Manual
1' Heads gen 2-5 per cluster, phyllaries not scarious-margined, bases +/- persistently tomentose
C. pycnocephalus ssp. pycnocephalus
1'' Heads 5-20 per cluster; phyllaries scarious-margined, bases glabrous or sparsely tomentose, tips glabrous or barely scabrous, sometimes minutely scabrous-ciliate C. tenuiflorus

Key from Flora of the PNW, 2nd edition
1' Heads in cluster of 2-5; phyllary margins membranous, base woolly-hairy, tip minutely rough-hairy (hairs forward-pointing); achene 4-6 mm; papus 15-30 mm C. pycnocephalus
1'' Heads in cluster of 5-20; phyllary margins scarious, base generally glabrous or sparsely woolly -hairy, tips glabrous, scabrous, or ciliate; achene 4-5 mm; pappus 10-16 mm C. tenuiflorus

Key from Flora Europea:
2' Peduncle more than 3 cm C. pycnocephalus
2'' Peduncle absent or not more than 3 cm
8' Leaves with 6-10 pairs of lobes C. tenuiflorus
8'' Leaves with 2-5 pairs of lobes C. pycnocephalus

FNA (Flora of North America)
Carduus pycnocephalus ssp. pycnocephalus -- Annuals, 20-200 cm. Stems simple to openly branched, losely tomentose with fine single-celled hairs and villous with curled, sepate hairs; teeth of wings to 10 mm, wing spines to 20 mm. Leaves: basal tapering to winged petioles, blades 10-25 cm, margins pinnately 2-5-lobed, abaxial faces +/- tomentose, adaxial faces tomentose and pilose, +/- glabrous; cauline sessile, shorter, margins less divided, distally reduced to bracts. Heads borne singly or clustered in +/- tight groups of 2-5 at ends of branches and sometimes in upper axils, sessile or short-pedunculate, 20-25 mm. Peduncles winged throughout or distally unwinged, 0-2 cm, tomentose. Involucres cylindric to elipsoid (appearing campanulate when pressed), 17-22 mm x 7-15 mm (diameter). Phyllaries linear-lanceolate, with appressed, loosely tomentose bases 2-3 mm wide and ascending, linear apendages 0.5-1.5 mm wide, not scarious-margined, distally scabrous on midribs and margins, spine tips 1-3 mm, the inner straight, erect, with unarmed or minutely armed tips. Corollas +/- purple, 14-16 mm, lobes ca. 3 times longer than throat. Cypselae golden to brown, 4-6 mm, finely 20-nerved; pappus bristles 15--20 mm.

Carduus tenuiflorus -- Annuals, 20–200 cm. Stems simple or openly branched, loosely tomentose with fine single-celled hairs and villous with curled, septate hairs; teeth of wings to 25 mm, wing spines to 15 mm. Leaves: basal tapered to winged petioles, blades 10–25 cm, margins pinnately 6–10-lobed, abaxial faces tomentose, adaxial faces loosely tomentose and villous or ± glabrate; cauline sessile, shorter, less divided. Heads clustered in ± tight arrays of 5–20+ at ends of stems, usually sessile, 15–22 mm × 7–12 mm. Peduncles [omitted]. Involucres cylindric to ellipsoid (appearing campanulate when pressed), 15–20 × 7–12 mm. Phyllaries linear-lanceolate, bases appressed, 2–2.5 mm wide, ± glabrate, and ascending, appendages 0.5–1.5 mm wide, narrowly scarious-margined, distally glabrous or minutely ciliolate, spine tips 1–2 mm, inner phyllaries with erect, straight, unarmed tips. Corollas pinkish, 10–14 mm; lobes 1.5–2.5 times longer than throat. Cypselae brown, 4–5 mm, finely 10–13-nerved; pappus bristles 10–15 mm. 2n = 54.

Carduus pycnocephalus and C. tenuiflorus are similar annuals with small, usually tightly clustered heads. The number of heads per capitulescence is usually ultimately greater in C. tenuiflorus, but early season plants of this species often have only a few heads. At the end of the growing season the fruiting heads of C. tenuiflorus are aggregated in dense, subspheric clusters. Stem wings tend to be more pronounced in C. tenuiflorus. Fresh corollas of C. pycnocephalus are rose-purple whereas those of C. tenuiflorus have a more pinkish tinge, but this difference is subtle and not reliable on herbarium material. The phyllaries of C. tenuiflorus are membranous-margined, more or less glabrate, and lack the short, stiff, upwardly appressed trichomes of C. pycnocephalus. All published chromosome counts for Carduus tenuiflorus from both Old and New World material are the same.

The two species sometimes grow in mixed populations and at times appear to intergrade. Hybridization has been reported in Europe (S. W. T. Batra et al. 1981) and is suspected to occur in California. Hybrids between C. pycnocephalus and C. tenuiflorus have been designated Carduus ×theriotii Rouy.

STACE, New Flora of the British Isles:
Cardus tenuiflorus -- Stems erect, to 60(80) cm, continuously spiny-winged up to capitula; leaves grey- to white-cottony on lower side; capitula +/- sessile, in clusters of (1)3-10, 12-18 x 5-10 mm (excl. flowers), +/- erect; corollas mostly shorter than phyllaries (POWO -- native W Europe and NW Africa, introduced to South Africa; introduced to other continents. = C. pycnocephalus ssp. tenuiflorus)

Carduus pycnocephalus -- Differs from C. tenuiforus in stems and leaves more densely white-cottony; capitula subsessile to stalked, in clusters of 1-3, 14-20 x 7-12 mm (excl. flowers); corollas mostly longer than phyllaries. (POWO -- North Africa and Ethiopia)

JEPSON MANUAL:
Carduus pycnocephalus ssp. pycnocephalus -- Annual. Stems 2-10 dm, glabrous or slightly woolly, narrowly spiny-winged. Leaves: basal 10-15 cm, 4-10-lobed; cauline +/- tomentose. Inflorescences: Heads generally 2-5 per cluster, sessile or short-peduncled; involucre 1-2 cm diameter, cylindric to ellipsoid; phyllary base +/- persistently loosely tomentose, margin not scarious, tip ascendign, lance-linear, scabrous. Flowers: Corolla 10-14 mm, pink to purple; tube 5-8 mm, throat 2-3 mm, lobes 4-5 mm. Fruit: 4-6 mm, golden to brown; veins 20, pappus 10-15 mm.

Carduus tenuiflorus -- Annual. Stems 2-20 dm, glabrous or slightly woolly, widely spiny-winged. Leaves: basal 10-15 cm, 12-20-lobed; cauline +/- tomentose. Inflorescence: Heads 5020 per cluster, ssessile or short-pedunculed; involucre 1-2 cm diameter, cylindric to ellipsoid; phyllary bases glabrous or thinly tomentose, margins scarious, tips ascending, lance-linear, glabrous or barely scabrous, sometimes minutely scabrous-ciliate. Flowers: Corolla 10-14 mm, pink to purple; tube 4-6 mm, throat 2-3 mm, lobes 4-5 mm. Fruit: 4-5 mm, brown; veins 10-13; pappus 10-15 mm.

FLORA EUROPEA
Carduus pycnocephalus Annual up to 80 cm. Stem arachnoid-hairy but greyish-tokmentose above; wings up to 5 mm wide, triangular, with an apical spine up to 5 mm. Leaves oblanceolate to oblong-lanceolate, sparsely hairy above, arachnoid-lanuginous beneath with mostly unicellular hairs, with 2-5 pairs of palmate lobes, each with an apical spine up to 12 mm. Capitula 15-20 x 7-13 mm, cylindrical, subsessile or on peduncles up to 10 cm and 2 mm in diameter, solitary or in clusters of 1-3; involucral bracts imbricate, arachnoid-hairy; inner bracts up to 1.25 times as long as th emiddle, faintly 3-veined in the distal half, not scarious at margin distally. Corolla 10-14 mm. Achenes 4-5 mm, compressed, smooth; apical prominencesmall,shortly stipitate, clavate, entire; pappus 10-14 mm.

Carduus tenuiflorus. Annual or biennial up to 75 cm. Stem more or less arachnoid-hairy; wings up to 10 mm wide, triangular, with an apical spine up to 5 mm. Leaves oblanceolate to lanceolate, sparsely hairy above, arachnoid hairy beneath, with mostly unicellular hairs, with 6-8 pairs of broadly triangular, acute lobes, each with an apical spine up to 5 mm. Capitula 15-20 x 5-10 mm, cylindrical, sessile, in compact clusters of 3-8(-12); involucral bracts imbricate but with suberect or patent apices 1.5-2 mm wide, ovate-lanceolate, more or less contracted at the apex, glabrous, smooth, with scarious entire margin, the mid-vein raised in the distal third; inner bracts 1.25 times as long as the middle bracts, veinless, subulate, with scarious, entire margin and apex. Corolla 10-14 mm. Achenes 4-5 mm, swollen, smooth; apical prominence shortly stipitate, clavate, entire; pappus 11-13 mm.

Carduus thistles present difficulties for the identiers. My first problem was finding out what Carduus live in Africa. This is a complete list of Carduus that POWO maps in Africa.

Another problem: Is it Carduus or Cirsium? If you've got the plant in hand, it's easy to tell: the pappus hairs (the ones on the seeds, to help them fly) are simple in Carduus but branched like feathers in Cirsium. From photos? Not useful. I think all Carduus have a basic "look" with their +/- winged stems and often white-marked leaves. Good luck.

The thistles with narrow heads, C. pycnocephalus or C. tenuiflorus, are very similar. See a separate journal entry just for them.

In several cases, we see what seems to be a totally distinctive thistle species, but then looking closer reveals that there are two or three very similar species there, too. Frustrating.

Key to the more common Carduus of England from Stace, Flora of the British Isles. "Capitula" = heads.

1. Capitula subcylindrical, <14 mm across (excl. flowers); corolla with 5 +/- = lobes

2. Capitula in clusters of 3-10; stems with spiny wings right up to base of capitula; phyllaries thin and transparent on margins, without strongly thickened midrib except sometimes near apex
   C. tenuiflorus

3. Capitula in clusters of 1-3; stems with discontinuous spiny wings, with at least some peduncles unwinged sitally; phyllaries with strongly thickend margins and midrib for at least distal half
   C. pycnocephalus
   1’ Capitula globose to bell-shaped, >14 mm across (excl. flowers); corolla with 1 lobe distinctly more deeply delimited than the other 4

4. Capitula 14-25(30) mm across (excl. flowers), in clusters of (1)2-4(5), +/- erect; phyllaries linear-subulate, not narrowed just above base; corolla 12-15 mm C. crispus / acanthoides
5. Capitula (20)30-60 mm across (excl. flowers), usually solitary, pendent; phyllaries lanceolate, narrowed just above base; corolla 15-25 mm C. nutans (& C. macrocephalus, but its heads are erect)

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WIDESPREAD WEEDY CARDUUS

Cardus tenuiflorus -- Stems erect, to 60(80) cm, continuously spiny-winged up to capitula; leaves grey- to white-cottony on lower side; capitula +/- sessile, in clusters of (1)3-10, 12-18 x 5-10 mm (excl. flowers), +/- erect; corollas mostly hsorter than phyllaries (POWO -- native W Europe and NW Africa, introduced to South Africa; introduced to other continents. = C. pycnocephalus ssp. tenuiflorus)

Carduus pycnocephalus -- Differs from C. tenuiforus in stems and elaves more densely white-cottony; capituls subsessile to stalked, in clusters of 1-3, 14-20 x 7-12 mm (excl. flowers); corollas mostly longer than phyllaries. (POWO -- North Africa and Ethiopia)

Carduus macrocephalus -- Very similar to C. nutans. Stace: it differs from C. nutans in its more densel pubdscent stems to 2 m, longer-stalked capitula, and shorter phyllaries with prominant (not obscure) midrib. (POWO -- native NW Africa [Morocco to Tunisia], N Mediterranean, Italy to Greece; introduced South Africa and elsewhere.) Carduus macrocephalus = C. nutans ssp. macrocephalus = C. nutans var. macrocephalus. A part of the Carduus nutans complex.

Carduus nutans -- Stems erect, to 1 m, discontinuously spiny-winged with peduncles unwinged distally; leaves pubestent on lower side; capitula stalked, mostly solitary, 16-30 x 20-60 mm (excl. flowers), depressed-globose, pendent, with strongly reflexed outter phyllaries. (POWO -- Native Eureasia, east to China. Widely introduced elsewhere but not in Africa.)

Carduus acanthoides (sensu stricto) -- differs from C. crispus in its longer-spined (c. 5 mm, not ca. 2-3 mm) stem-wings, web-like pubescent (not subglabrous) stems, and usually larger (25-35 mm across) solitary capitula. (POWO -- in Libya, not elsewhere in Africa)

Carduus crispus (C. acanthoides auct. non L.) -- Stems erect, to 1.5 m, continuously spiny-winged up to or nearly up to capitula; leaves subglabrous on lower side; capitula mostly stalked, in clusters of (1)2-4(5), 9-15 X 15-20(25) mm (excl. flowers), bell-shaped, +/- erect. (POWO -- not in Africa)
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Not sure how to group these Carduus of central eastern Africa.
Carduus macracanthus -- POWO: The native range of this species is Ethiopia.
Carduus silvarum -- POWO: The native range of this species is Kenya.
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CARDUUS OF CENTRAL AFRICA, with heads crowded in a cluster and usually very spiny stems and leaves, the leaves much divided

Carduus afromontanus -- POWO: The native range of this species is Kenya to Uganda.

Carduus keniensis -- POWO: The native range of this species is E. Tropical Africa. (Kenya, Tanzania, Uganda). -- Leaves long, mostly basal, Ascending to erect, very 3-D. Lots of heads in a cluster. Very spiny. Mountains only.

Carduus leptacanthus -- POWO: The native range of this species is Ethiopia to E. Central & E. Tropical Africa.

Carduus millefolius -- POWO: The native range of this species is Kenya. -- Leaves very long and narrow, with very short lobes. Stem with crowded spines all the way up. Heads several, crowded. Strange.

Carduus nyassanus -- POWO: The native range of this species is Nigeria to Ethiopia and S. Tropical Africa. -- Looks like Carduus keniensis light to me. Leaves not so 3-D and much more horizontal, but a very spiny, stout thistle with a big cluster of crowded heads.

Carduus ruwenzoriensis -- POWO: The native range of this species is E. DR Congo to Uganda (Ruwenzori). I know nothing about this.

Carduus schimperi POWO: The native range of this species is Ethiopia to Tanzania. This is a flat thistle. Leaves lie on the ground like a big spiny plate. A cluster of large heads is sessile or nearly so in the center of the plate.
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ENDEMIC CARDUUS OF THE CANARY ISLANDS. Surprising diversity. Carduus pycnocephalus and C. tenuiflorus grow there, too.

Carduus baeocephalus -- POWO: The native range of this species is Canary Islands (Tenerife).

Carduus bourgaei -- POWO: The native range of this species is Canary Islands (Fuerteventura). -- flat leaves.

Carduus clavulatus -- Canary Islands, only. Flat leaves.

Carduus squarrosus -- POWO: The native range of this species is Madeira.

Carduus volutarioides -- POW: The native range of this species is Canary Islands (Tenerife).
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CARDUUS OF NORTH AFRICA, not found further south in Africa. Impressive and confusing diversity. I know I'm not going to ID Carduus from this area.

Carduus acicularis -- POWO: The native range of this species is Switzerland to Medit. and Iraq. It is an annual and grows primarily in the subtropical biome. -- also mapped in Libya & Egypt.

Carduus arabicus -- POWO: The native range of this species is SE. Europe to Central Asia and N. Pakistan, Arabian Peninsula. It is an annuale. -- actually just in the Sinai, not the African part of Egypt, apparently.

Carduus argentatus -- POWO: The native range of this species is E. Medit., Pakistan. It is an annual and grows primarily in the subtropical biome. -- mapped in Libya & Egypt.

Carduus argyroa -- POWO: The native range of this species is France, S. Italy, Sardegna, Sicilia, Algeria, Tunisia.

Carduus ballii -- POWO: The native range of this species is Morocco.

Carduus bourgeanus -- POWO: The native range of this species is SE. Portugal to Central & S. Spain, Morocco.

Carduus chevallieri -- POWO: The native range of this species is Morocco to Algeria.

Carduus getulus -- POWO: The native range of this species is N. Africa to Iran and Arabian Peninsula. It is an annual.

Carduus leptocladus -- POWO: The native range of this species is NW. Africa. It grows primarily in the subtropical biome. -- Algeria & Morocco.

Carduus maroccanus POWO: The native range of this species is Morocco. It grows primarily in the subtropical biome.

Carduus martinezii -- POWO: The native range of this species is Morocco. It grows primarily in the subtropical biome.

Carduus myriacanthus -- POWO: The native range of this species is SW. Spain (to Gibraltar), Morocco to Algeria.

Carduus myricanthus -- POWO: The native range of this species is SW. Spain (to Gibraltar), Morocco to Algeria.

Carduus numidicus -- POWO: The native range of this species is Algeria.

Carduus spachianus -- POWO: The native range of this species is N. Africa.

Macledium -- Small shrubs, or some look like tough herbs. Juvenile leaves, and all leaves in some species, flat, entire. In mature plants, some or all of the leaves are like the narrow, acute, almost spine-like bracts below the inflorescence. One head arises at the branch tip, surrounded by spike-like or broaded, often colorful, striped bracts. The pappus seems to consist of flat structures that may be somewhat or extremely lacerate often looking like a fluffy white matrix that the florets grow in. The head may consist of so few flowers (e.g. 7) that it’s hard to perceive the plant as a composite, but there may be more. Watch for flower color (yellow in norther species I can find little information about, pink or brown to the south), number of flower/head (7-20 or 30+), and leaf type (flat below the inflorescence bracts, or all narrow and pointed).

Macledium spinosum, Spiny Dollprotea -- Very small shrub. Leaves seem to be entire, smooth-margined ovate leaves with acute tips. However, some of the photos show leaves with a few large teeth and other show very narrow leaves. There’s a cluster of long, spine-like bracts at the tip of the branches, below the flower. One flower at each branch-tip. Phyllaries broad near the base, acuminate (to obtuse?). Phyllaries pink to reddish with narrow to wide white edges. Flowers 7 to 18 in the open cup of the phyllaries. Pappus white, flat, divided lengthwise, not extending all the way to the spreading corolla lobes. Corollas white basally, pink distally, the 5 lobes entire, spreading. Range in South Africa and extending up the middle of the continent for a ways. North on coast to Durban but not much beyond that, I think.

Macledium latifolium -- Much like M. spinosum and often considered a member of that species. Down near the Cape. Leaves very small, upper surface glossy. Margins entire or with a few shallow teeth.

Macledium relhanioides, Quartz Dollprotea -- Very limited range in South Africa. Juvenile leaves elliptic, soft-looking, gray-felty, like those of M. spinosum, but these leaves are usually not visible. Mature leaves lanceolate, tapered evenly to a spine-like tip, like the bracts but not colorful. Cluster of bracts similar to mature leaves. Phyllaries broad near the base, acuminate at tip, pink basally and white around tip and margins (or entirely white), like those of M. spinosum. Pappus white, flattened, divided lengthwise distally, extending all the way to the spreading corolla lobes or even further. Corollas, few, proximally white, distally pink, with 5 spreading lobes.

Macledium zeyheri, Silver Dollprotea -- Inflorescence more branched than M. spinosum, more obviously with 2 or more flowers on branches from the same main branch. Most leaves flat, softer, lanceolate with rounded tip, sometimes petiolate (but see M. z. argophyllum). Leaves below the flowering head, on its branch, narrow, lanceolate, tapering evenly to a spine-like tip, markedly different from the other leaves. They grade into the bracts below the head, which are narrowly to broadly dark with white edges. Inner ones may be white. Innermost ring of phyllaries half or less the length of the bracts, barely longer than the flowers, usually(?) erect with tips spreading. Pappus not easily seen during flowering except as a white matrix from which the flowers arise. Corollas 30-40+, maroon to brown, crowded. Range Durban and north and west from there.

Macledium zeyheri ssp. zeyheri -- Range seems to include the others. From south of Durban on the coast, north Haenertsburg, inland to west of Johanesburg and Pretoria.

Macledium zeyheri ssp. argophyllum -- Branching mainly from the base. Leaves narrow and spine-like all the way down (except maybe in response to injury?). Bracts seeming more numerous and mostly white (usually). Range coastal, from a little south/west of to northeast of Durban, but not north to Maputo. Looks like a good garden subject.

Macledium zeyheri thrysiflorum -- Substrate serpentine. Most leaves strap-like. Maybe fewer flowers than the other subspecies. Range very limited, west of Maputo.

Macledium speciosum -- Leaves narrow, flat, long, strap-like. Bracts a spreading, somewhat elongated cluster, often separated from the leaves by bare stem. Numerous. Innermost phyllaries shorter than bracts, white. Pappus much divided, the lobes branched, forming a white cushion in which the corollas are embedded. Corollas ~30, dark brown. Limited range, a little south of Durban to Eswatini, coastal or somewhat inland.

Macledium grandidieri -- Branched shrub. Leaves all of the pointed type, spine-tipped, but they’re a bit broader and more grooved than in the most common species. Corolllas pink to white. Madagascar, probably the only species there.

Macledium sessiliflorum -- Most leaves linear or narrowly lanceolate. There may be two or more heads crowded together at the tip of a branch. Bracts and tight cluster on a mostly bare stem, longer, narrower, than those of the other species, needle-like. Corollas yellow. Range north of the three common ones, Zimbabwe, Mozambique, Zambia, DRC.

Macledium kirkii -- Leaves strap-like. Bracts almost needle-like, spreading more than in M. sessiliflorum. Heads on branches, but not crowded. Flowers yellow. Zambia, Mozambique.

Macledium plantaginifolum -- very little data. Zambia. One with spine-like leaves maybe.

Tarchonanthus -- Camphorbushes. Leaves have a strong smell of camphora, a great help in the field but not in photos. Upper surfaces of leaves are dull and more strongly textured than in Brachylaena. Lower leaf surfaces are densely felty-hairy. Young shoots are often densely whitish hairy, older less so but still dull. Flowers are small, off-white, in panicles. Plants are dioecious. Females produce seeds in little balls of white, cottony hairs -- the clusters can be seen from a long distance. Brachylaena can produce fruits like this, but often don’t seem to. Species fewer than in Brachylaena and I have some hope of distinguishing them. Note: All (or at least T. littoralis) used to be included in T. camphoratus, but now they’ve been split. People are still confused by this.

Tarchonanthus camphoratus. Shrubs in Kenya are this species. Not any of the other Tarchonanthus species grow there. There are reports elsewhere -- accurate or left-over from earlier taxonomy? Apparently widespread elsewhere to the south and west, but maybe not in South Africa itself. Leaves elliptical or broadly linear.

Tarchonanthus littoralis. Shrubs along the coast. Common and very commonly photographed. Leaves elliptical, very much like T. camphoratus. Can be ID’d by range from the Cape to Durban, but from there east and north range overlaps with other species, so be careful.

Tarchonanthus minor. Leaves very small but much like those of T. littoralis. Inflorescence more sparse. Generally inland, in a swath parallel to the coast. Mostly avoid IDing this, but occasionally it’s clear you’re seeing one.

Tarchonanthus parvicapitulatus. Leaves narrower than those of T. littoralis, similar to some of those in T. camphoratus. Leaves white-felty below, dull but not textured above. Range from the coast to inland, north of Lesotho, overlapping with other species. Don’t usually ID it.

Tarchonanthus trilobus. Range like that of T. parvicapitulatus and T. minor. Many plants have broad, three-lobed leaf tips, which isn’t quite as much help as it seems like it should be. Leaf margins tend to be wavy in 3-D. Lower leaf surfaces are felty-hairy below but I don’t think they’re white. Young leaves are densely hairy above, but it wears off. Some plants have unlobed leaf tips, similar to those of T. littoralis. Worse, one or two species of Brachylaena can have lobed leaves like those of T. trilobus, though they usually don’t. Their leaf upper surfaces are shinier than those of T. trilobus and I think they lack the 3-D wavy margins, but they’re confusing.

Dicroma. At least one species can be a shrub. Others are herbs. Leaves tend to be shorter than in Tarchonanthus or Brachylaena.

Brachylaena -- Silver Oaks. Common and diverse. Upper surface of leaf usually smooth and shiny at least when mature, though lower surface is densely felty-hairy. Young shoots may have leaves densely gray or whitish hairy, but it seems to wear off. Usually the leaves are entire, but one or two species can have 3-lobed tips, like Tarchonanthus trilobus. Flowers a panicle, small, whitish. So far I don’t understand the species, and won’t try to ID them, but but B. ramiflora of Madagascar seems distinctive with its flowers in short clusters on main stems. Fruits of Brachylaena can be all woolly like in Tarchonanthus, but I think often are not.

This is the start of an irregular series that will cover identification of genera or other groupings of the African Carduoideae. As part of Mission Impossible -- Identify Plantae in Africa (see https://forum.inaturalist.org/t/mission-impossible-identify-plantae-in-africa/43528 in the forum), I have worked on these plants. Or perhaps blundered through African thistles leaving chaos in my wake. We'll see.

I am learning about what thistles and relatives grow there and how to identify some of them. I plan to post what I've learned here, for three reasons. First, I'll have the information available for me to use. Second, perhaps you will find some of it useful. Third, I hope you can correct or expand what I've written. I'd love to get more information about these plants and how to identify them. I may get to be embarrassed by how much less I've learned than I thought I did, but so it goes.

This Mission will last through August. It's intended to reduce the huge backlog of unidentified or Needs ID plants that has been frustrating and discouraging those trying to identify African plants. They've been watching the pile of Needs ID observations increase despite their hard work. Although identifying plants to species is of course valuable, in this case it's just as important to search through "Plants" or "Unknown" or other high taxonomic groups to try to bring those observations to a lower level. Please help if you can this month.

-- Barbara

Letters to a Pre-Scientist is a program that pairs students (about 6th through 9th grade, but if varies) with people involved in science, technology, engineering, or math (professionals, grad students, etc.). It's a great program. It's sign-up time! Please participate! See https://prescientist.org/

Through the program, the student writes four letters (physical letters) to you over the course of the school year and you respond to each one. Many of the kids have never written or received a letter before. The hope is that you'll make science seem more accessible to the student, but just corresponding with an adult is a learning experience for them.

On-line training is required, some time in August.

All students in each class participate, so you may hear from excellent students or really poor ones. Classes are usually in financially stressed areas.

Please participate in this program.