In 1911 a botanist presented the rooibos shrub as a new species

On Wednesday, 17 May 1911, the botanist Rudolf Marloth read a paper to the Royal Society of South Africa, with the society's president, S. S. Hough, in the chair. The paper was "Some new South African succulents and other plants. Part IV."¹ One of the plants it described as new was a shrub Marloth called Borbonia pinifolia, which he gave as the source of a tea he spelled "rooibosh tea".

1. Marloth, Some New South African Succulents and Other Plants, Part IV, Transactions of the Royal Society of South Africa vol. 2 (read 17 May 1911, printed 1912)

Nicolaas Burman had published the same plant as Psoralea linearis in 1768⁴, 143 years before Marloth read his paper.

4. International Plant Names Index, Psoralea linearis Burm.f. (1768)

A short report of the evening appeared in the South African Journal of Science². It said Marloth had described "a Borbonia, the source of Cape 'rooibos' tea." The Dictionary of South African English³ gives that 1911 report as its earliest citation for "rooibos" as the name of the tea.

2. Royal Society of South Africa, proceedings of 17 May 1911, South African Journal of Science vol. 7, p. 374
3. Dictionary of South African English, rooibos

Marloth's paper opened by naming three species "of special interest": a Cytinus, a Borbonia and an Anacampseros. The Cytinus was the second South African member of the Rafflesiaceae, and the Anacampseros was "another example of a mimicry-plant". The Borbonia, he wrote, "is of economic importance, being the source of a colonial tea, viz., rooibosh tea."¹

1. Marloth, Some New South African Succulents and Other Plants, Part IV, Transactions of the Royal Society of South Africa vol. 2 (read 17 May 1911, printed 1912)

The dictionary traces "rooibos" to Afrikaans, rooi (red) and bos (bush), and notes that it was "formerly also rooibosch."³

3. Dictionary of South African English, rooibos

In the printed paper Marloth gave the tea two more names, "naald-thee" and "koopmans-thee". The dictionary's entry carries the same pair in a 1973 citation, which lists "Naald tea or Speld tea (Needle tea) and Koopmans tea (merchants tea)."³

3. Dictionary of South African English, rooibos

His Latin description begins "Frutex bipedalis, foliis simplicibus, teretibus, filiformibus": a shrub two feet tall, with simple, cylindrical, thread-like leaves. He wrote that the plant "has the appearance of a Rafnia"¹, but that the structure of its ovary and its silky corolla placed it in Borbonia. He recorded it flowering in December and January, and filed his specimen as Marloth No. 4728.

1. Marloth, Some New South African Succulents and Other Plants, Part IV, Transactions of the Royal Society of South Africa vol. 2 (read 17 May 1911, printed 1912)

The shrublet, Marloth wrote, "occurs apparently only on the Cedar Mountains near Clanwilliam and Wupperthal,"¹ yet it supplied a tea "now so largely used in South Africa".

1. Marloth, Some New South African Succulents and Other Plants, Part IV, Transactions of the Royal Society of South Africa vol. 2 (read 17 May 1911, printed 1912)

Van Wyk and Gorelik, in a 2017 review of Cape herbal teas⁸, conclude that rooibos became generally known in the Cape only between 1902 and 1912. They report that it was displayed at the South African Exhibition in London in 1907, and sold as far from its habitat as Worcester at least since the years 1902 to 1904.

8. Van Wyk & Gorelik, The history and ethnobotany of Cape herbal teas, South African Journal of Botany 110 (2017)

The review notes that Marloth married Marian Van Wyk of Clanwilliam in 1891 and undertook a botanical expedition to the Gifberg and Cederberg in 1901. Its authors call it "curious"⁸ that neither MacOwan in 1894 nor Marloth in 1909 mentions rooibos tea in their reviews of Cape medicinal products.

8. Van Wyk & Gorelik, The history and ethnobotany of Cape herbal teas, South African Journal of Botany 110 (2017)

Burman's 1768 species name is the root of the plant's modern name, Aspalathus linearis. Between Burman and Marloth, Meyer had published another name for it, Aspalathus corymbosa, in 1832⁵.

5. International Plant Names Index, Aspalathus corymbosa E.Mey. (1832)

Marloth's description also covered only part of a variable plant. Van Wyk and Gorelik write that he "described the Wupperthal form of rooibos as a new species"⁸. Because the paper was read in 1911 and printed in 1912, the International Plant Names Index⁶ dates Borbonia pinifolia to 1912, at page 238 of the Transactions.

8. Van Wyk & Gorelik, The history and ethnobotany of Cape herbal teas, South African Journal of Botany 110 (2017)
6. International Plant Names Index, Borbonia pinifolia Marloth (1912)

In a list of plant names published in 1917, Marloth kept his own name and gathered the tea's common names under it: "Rooibos tee, Rooi tee, Naald tee or Koopmans tee, is Borbonia pinifolia; a small shrublet of the Olifant's river and Cedar mts."⁸ He added that the twigs and leaves "are cut up and fermented like the Cyclopia", and gave Spelde tee as another name for Rooi tee.

8. Van Wyk & Gorelik, The history and ethnobotany of Cape herbal teas, South African Journal of Botany 110 (2017)

By his Flora of South Africa in 1925 he had moved the plant. There it appears under Meyer's Aspalathus corymbosa, with Borbonia pinifolia listed as a synonym. Marloth wrote that "this shrublet yields the rooibostee (naald tee) now largely used in South Africa"⁸.

8. Van Wyk & Gorelik, The history and ethnobotany of Cape herbal teas, South African Journal of Botany 110 (2017)

Neither Marloth's name nor Meyer's is the one in use. In 1963 the botanist Rolf Dahlgren published the plant as Aspalathus linearis (Burm.f.) R.Dahlgren⁷, building the current name on Burman's 1768 species name, the oldest of the three.

7. International Plant Names Index, Aspalathus linearis (Burm.f.) R.Dahlgren (1963)