Eugenia myrcianthes: the Mystery Tree in Orpet Park
Randy Baldwin, San Marcos Growers
March 2017

The unusual and attractive tree growing along Moreno Road at the edge of upper Orpet Park in the Santa Barbara Riviera has long gone misidentified as Myrciaria edulis and later as Plinia edulis. In 2016 an interenet blog questioned this identification and generated speculation as to its true identity. This tree in the Myrtle Family (Myrtaceceae) has thin pendulous branches holding elliptic-oblong leaves that are 2 to 3 1/2 inches long by 1/2 to 3/4 of an inch wide and bears white flowers with long stamens in late winter into spring. Most notable in the early summer when the tree produces an abundance of orange-yellow fruit that is attractive on the plant and then decoratively litters the ground beneath. When this plant is in fruit it is so noticeable to those who pass by that I regularly field inquiries about its identity and, up until a few years ago, felt confident that I answered these inquiries correctly, at first with the name Myrciaria edulis and in later years with the newer name Plinia edulis, as this tree was well described in Santa Barbara tree books. In the older books it was listed as Eugenia edulis or Myrciaria edulis and this very tree later pictured in Bob Muller and Bob Haller's more recent Trees of Santa Barbara, published by the Santa Barbara Botanic Garden in 2005, with the more current name, Plinia edulis, with Myrciaria edulis listed as a synonym.

This name came under question in 2016 in a local Santa Barbara internet blog called EdHat. Though most comments seemed to be wild guesses or even off topic remarks, there were also some very good observations which prompted me to look further into the name Plinia edulis (Vell.). In the end I had to conclude that this plant had long been incorrectly identified, and it was actually Eugenia myrcianthes Nied. as described by the German botanist Franz Josef Niedenzu in Die Natürlichen Pflanzenfamilien in 1893. To confirm this I inquired about this identification with the Brazilian botanist, Dr. Marcos Sobral, who is a noted expert on the South American eugenias and is referenced as such in Flora do Brasil (Flora of Brazil). Dr. Sobral confirmed this identification and noted that this plant and Plinia edulis have been confused by others as well. Interestingly, the confusion between these plants predates this plant's existence in Santa Barbara and somewhat explains how this plant was first misidentified here and how this erroneous name and synonyms persisted for so long.

Eugenia myrcianthes had been previously known as Hexachlamys edulis, Myrcianthes edulis and also illegitimately as Eugenia edulis. In the collaboration between the Royal Botanic Gardens Kew and Missouri Botanical Garden (MOBOT), the index called The Plant List lists a synonym for Eugenia myrcianthes as Eugenia edulis (O.Berg) Benth. & Hook.f. ex Griseb. [Illegitimate]). This listing indicates that these plants had been confused before and continued to be so as the actual Plinia edulis (Vell.) (Syn.Eugenia edulis Vell.) is clearly quite different from the Orpet Park tree. While there are other characteristics that distinguish these two species, one quite notable difference is that Plinia edulis, commonly called cambucazeiro, bears its shiny roundish fruit, called cambucá, on hard wood (cauliflorous) while the Orpet Park tree, Eugenia myrcianthes Nied. has a more elongated dull yellow fruit borne on the slender stems out near the edges of the canopy. The listing for Eugenia myrcianthes in the Flora Do Brasil has herbarium sheets showing this plant and lists its distribution within Brasil (Brazil). The website of the Federal University of Rio Grande in Rio Grande do Sul also has good pictures of this species at Eugenia myrcianthes that clearly shows the same plant as in Orpet Park.

In Santa Barbara the confusion regarding this tree can be seen in the many books published about the trees of the area, starting with Maunsell Van Rensselaer in his 1948 Trees of Santa Barbara, where he listed Eugenia edulis, though he did not include this species it in his original 1940 edition of this same book. Van Rensselaer did not note the specimen at Orpet Park so it is not clear whether this tree existed in the park then, but he described plants with pendulous willow-like foliage and yellow fruit growing elsewhere in the Santa Barbara Riviera. He also noted that the tree had been "introduced at Santa Barbara by Dr. F. Franceschi many years ago" - this written in 1948! It is quite possible that Van Rensselaer got this identificaion from Peter Riedel, who was a partner with Franceschi(AKA Emanuele Orazio Fenzi)in his California Acclimatizing Association nursery and then in 1909 took over the California Acclimatizing Association.

Peter Riedel included Eugenia edulis in his manuscript Plants for Extra-tropical Regions (published after Riedel's death in 1957) with the note that it was a Franceschi introduction in 1908 and "from the river Plata in Brazil". Interestingly this is an area where Eugenia myrcianthes comes from, so likely this mistaken identity goes back to when the seed was first received by Franceschi as Eugenia edulis. In the Spanish language listing in Wikipedia for Hexachlamys edulis, the translation states "It grows in the coastal mountains of the subtropics of Brazil, Uruguay, Paraguay and Argentina, from the Chaco region to the coast of Rio de la Plata". Like Van Rensselaer, Riedel makes no mention of the specimen at Orpet Park so likely it was planted later or was too small for him to list, but he noted that "There are still a few specimens in Santa Barbara, survivors of those Dr. Franceschi grew, the best one on Dr. Franceschi's old nursery, just above Franceschi Park, a specimen 18 feet tall with a very graceful habit, pretty at all times but a spectacle when yellow with fruit which, in some seasons completely obscures the foliage."

In Katherine Muller, Richard Broder and Will Beittel's Trees of Santa Barbara, published by the Santa Barbara Botanic Garden in 1974, the authors, again without referencing the specimen in Orpet Park, identify this tree as Myrciaria edulis, the then current name for Eugenia edulis, which they also listed as a synonym. They noted it native to Brazil with:

"the only mature specimen then known a dense spreading tree evergreen tree to 25 feet tall with pendulous branchlets resembling a weeping willow. The glossy green elliptic leaves are 1 1/2 to 3 inches long and 1/4 to 3/4 inch wide. Young leaves and branches are covered with a fine fuzz. White flowers 1/2 inch across appear in the leaf axils from March to May. The rounded fruit with thin orange-yellow skin are abundantly produced. They are edible with a flavorful juicy pulp. Rare. A tree in a private garden above Franceschi Park, planted by Dr. Franceschi before 1913. A few seedlings from this tree planted in private gardens are now 5 to 10 feet tall."

In the Trees of Santa Barbara, written by Robert Muller and Robert Haller and published by the Santa Barbara Botanic Garden in 2005, this tree is listed under the new name Plinia edulis, with Myrciaria edulis listed as a synonym and includes pictures of the tree in Orpet Park. In 2016 I inquired with Bob Muller about this listing and he told me that neither he or Bob Haller investigated the identity of the tree because it has been well documented in the previous Santa Barbara tree books.

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