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RON PARKER Agaves of part II While the first Agaves of Arizona installment featured naturally occurring Agaves definitively placed in one subgenus (Agave) or the other (Littaea), our second installment continues with a venture into the somewhat more tenuous realm of naturally occurring hybrids and anthropogenic (literally, man-made) cultivars, in other words, the fun stuff! A peek back at Part I in vol. 89-6 might lend a sense of continuity, as reference is made to several taxa previously discussed. Please note that range maps exclusively represent sites we have personally vis- ited and documented. Naturally Occurring Hybrid Agaves

Agaves hybridize wherever they meet, provided they have overlapping bloom times and pollinators. There are three named hybrids in Arizona, and each is a cross between one of the first group (Agave Aga- ves) with one of the second (Littaea Agaves), resulting in progeny that look quite different from either par- ent. In each case, these hybrid Agaves are extreme- ly rare. Many additional hybrids, which bear some resemblance to one parent or the other, remain undescribed more times than not.

Agave ×arizonica was originally discovered in the 1. Agave ×arizonica, one of only two known examples 1960s, and Howard Scott Gentry himself apparent- in habitat. ly failed to realize he had come across the naturally occurring hybrid, A. chrysantha × A. toumeyana, instead aligning the taxon with A. utahensis, presumably due to a similar racemose . This may be the world’s rarest named Agave, as we know of only two living examples in habitat, miles apart in very remote sections of the New River Mountains (Fig. 1). A. ×ari- zonica seems poorly adapted to the harsh envi- ronment in which its parents reside. Sun and heat don’t seem at issue, but inadequate hydra- tion resulting from prolonged drought condi- tions has taken an unfortunate toll on habitat populations since its discovery. Though scarce in habitat, it offsets freely when adequate- ly watered in cultivation, and is frequently available from Desert Botanical Garden sales, and less commonly at nurseries. It is an extremely attractive small Agave, equally at home when cultivated in ground or containers. We have found a single example of a back- crossed Agave ×arizonica × A. toumeyana var. bella in habitat (Fig. 2). 2. Agave ×arizonica × A. toumeyana var. bella habitat hybrid.

20 Author Copy AND SUCCULENT JOURNAL delicate and vulnerable, with nar- row and no protective mar- ginal spines. Unlike its seed donor parent, leaves are not filiferous. When cultivated, A. schottii var. treleasei offsets prolifically, and is available in the retail nursery cir- cuit from time to time. Agave ×ajoensis is also rare, found only at a single locale at Organ Pipe National Monument in extreme southern Arizona, where A. deserti var. simplex and A. schottii share habitat. Once con- sidered conspecific with A. schottii var. treleasei, A. ×ajoensis was dis- covered to be distinct, and sub- sequently described by Wendy C. Hodgson (2001). Not surprisingly, it looks a great deal like A. schot- tii var. treleasei, only much lighter in color. Unfortunately, it is very diffi- cult to find in the trade, and the only known habitat population is currently under siege from eri- ophyid mites. This pernicious 3. Distribution of hybrid Agave in Arizona: A. ×arizonica ●, microscopic scourge scars sur- A. schottii var. treleasii ●, A. ×ajoensis ●. faces, interferes with reproduction, and even kills its hosts. Agave ×ajoensis is known to back-cross with A. deserti var. simplex.

4. var. treleasii from the Santa Catalina Mountains.

Agave schottii var. treleasei, currently considered a variety of A. schottii, is actually an A. schottii × A. chry- santha hybrid. It is nearly as scarce as A. ×arizoni- ca in habitat, growing in a few small clumps in the Santa Catalina Mountains near Tucson (Figs. 3 & 4). 5. Agave ×ajoensis growing in Organ Pipe National This 35–55 cm dark green Agave actually looks rather Monument.

2018 VOLUME 90 NUMBER 1 Author Copy 21 Domesticated Agaves

There are five named Agave taxa in Arizona, which we consider pre-Columbian cultivars. We associate these Agaves with indigenous pre- Columbian Native Americans, who presumably hybridized, selected, gardened and farmed these as sources of food, fiber, beverage, and building material, among other things. All feature a paniculate inflo- rescence. These Agaves are either sterile or reproductive- ly compromised, and many are still growing right where they were planted some 700–1000 years ago. Some may be sterile, but all offset prodigiously. Pre-Columbian culti- vars are really a lot of fun to chase out in habitat, because they’re always found near archeological sites, usually in small groups of three to thirty plants, almost always between 750–1500 m elevation along flats or gentle slopes, in what 6. Distribution of domesticated Agave in Arizona: A. murpheyi ●, generally present as garden A. delamarteri ●, A. phillipsiana ●, A. verdensis ●, A. yavapaiensis ●. settings (Fig. 6). Oft times, we’ll encounter terraces or an ancient dwelling, then look for associated Agaves, or perhaps just the reverse. To date we have found more than 330 such sites across Ari- zona, many of which were previously unknown. Once we grasped the concept of an intelligence behind their locales, we had a far easier time ferreting them out — best Easter egg hunt ever.

Agave murpheyi is the very first Arizona Agave recognized as a pre-Columbian cultivar, associat- ed with indigenous Native Americans. This came to light as botanists and archeologists collaborated in the mid-1980s to uncover an association with ancient archeological sites. Of A. murpheyi, Gentry (1952) writes "some of the clones appear to have been associated with old Indian living sites", so he may have suspected its status as domesticated, but appar- ently wasn't ready to commit, probably for lack of evi- from the Lake Pleasant area. dence at the time he penned his great tome. 7.

22 Author Copy CACTUS AND SUCCULENT JOURNAL 8. Hohokam archeological site high above an Agave murpheyi patch.

Outside the valley, A. murpheyi is rare and near- ly unknown, but in the Phoenix area groups of these 80–110 cm plants with ascending, dark green leaves are a common sight, often gracing medians and park- ways, rather like A. palmeri is utilized in the Tucson area. We have found A. murpheyi at Sierra Ancha, the Tonto Creek area, and close to the Mexican border, where it was reportedly once prevalent, but most are now found around Lake Pleasant and the New River area in startlingly harsh habitat that would turn many Agaves to ash (Fig. 7). It is the only Arizona pre- Columbian cultivar not endemic to our state, having also been found at several sites in northern . Not sterile, but reproductively compromised, A. murpheyi does produce small quantities of seed, along with copious numbers of bulbils, small plantlets that develop directly on bloom stalks (Fig. 9). Sim- ilar appearance and bulbil production have long led to speculation that A. murpheyi may be an A. angusti- folia hybrid, which reports of recent next-generation sequencing analysis conducted by Andrew Salywon Agave murpheyi bulbils. and Wendy Hodgson (2013) of the Desert Botanical 9. Garden apparently confirm. Other parts of the mur- pheyi equation remain a mystery, but look toward at Agave murpheyi is known to hybridize with A. least one putative parent that contributed cold hardi- chrysantha. ness to the mix.

2018 VOLUME 90 NUMBER 1 Author Copy 23 10. Agave delamateri from the heart of Salado country. A second Arizona pre-Columbian cultivar, Agave delamateri, was officially added to our catalog by Wendy Hodgson and Liz Slauson (1995). Original- ly discovered by Susan D. McKelvey, and named A. repanda by famed botanist William Trelease in 1929, he declined to publish for reasons unknown, and the ghosted taxon was subsequently misidentified by Gentry, who at one time considered it synonymous with A. palmeri, and A. chrysantha at another. A. delamateri is the most common of the Arizona pre-Columbian cultivars, in fact far more common than all others combined. From another perspective, it is actually more common than eight of the seventeen considered in this catalog. To date we have found it at more than 200 sites, and believe there are still more waiting to be discovered. It’s a mid-sized Agave, 70–100 cm, with an upright posture, blue and banded (Fig. 11), associated primarily with ancient Salado Native Americans in and around the Roosevelt 11. Agave delamateri with sharply ascending leaves. Lake region (Fig. 10). A delamateri is also found at Sierra Ancha and the Verde Valley. Although seed sterile, Agave delamateri does pro- This is a really tough Agave, often found in harsh, duce pollen, and has been found to hybridize with low elevation locales where other Agaves might per- A. chrysantha and A. murpheyi, although A. murpheyi ish. It is sterile, but offsets freely and has been culti- hybrids are a likely product of ancient Salado hor- vated by the Desert Botanical Garden for quite some ticultural intervention. We may have found A. dela- time, and they occasionally offer it for sale. A delama- materi × A. verdensis hybrids as well, but this remains teri is also found at Sierra Ancha and the Verde Valley. unconfirmed.

24 Author Copy CACTUS AND SUCCULENT JOURNAL 12. Sinagua cliff dwelling, associated with several Agave phillipsiana patches country near Sedona and south of Prescott. Quite similar to A. delamateri, A. phil- lipsiana seems more closely aligned with the ancient Sinagua culture than the Sal- ado (Fig. 12). Like its close cousin, it is sterile and boasts an expansive distribu- tion range, though it is far less com- mon. Perhaps it was as common at one time, we don’t know, but A. phillipsiana may not have fared so 13. Agave phillipsiana, perhaps 20 m from a Sinagua dwelling. well once its Native Agave phillipsiana is a personal favorite: tall, green, American caretak- and stately. Narrow 80 cm leaves are adorned with ers mysteriously vanished from the region several cen- an ample supply of haphazardly oriented needle-like turies ago. The expansive range of each, and incursion marginal spines (Fig. 13). Once believed endemic to into each other’s territory suggest some level of trade the area by Wendy C. Hodgson (2001), between ancient Salado and Sinagua cultures. it has since been found at numerous locales across central and northern Arizona, including red rock

2018 VOLUME 90 NUMBER 1 Author Copy 25 14. Agave verdensis poking through an Opuntia patch. Agave verdensis is a more recent find. It and A. yavapaiensis were not described until quite recently by W.C. Hodgson & A.M. Salywon (2013). At 50–60 cm (Fig. 14), this is a smaller plant than A. delamateri and A. phillipsiana, and in fact is easily confused with half grown A. delamateri, with which it associates. It has a very limited range, having not been found outside the Verde Valley (Fig. 15). This might suggest a more recent origin than the likes of A. delamateri and A. phillipsiana. Unlike our prior pre-Columbian cultivars, A. verdensis produces small quantities of seed in the upper one third of its inflorescence (Fig. 16). The area in which it grows, however, does not seem particularly conducive toward germination and seedling development, so reproduction is almost exclusively asexual. Agave verdensis may hybridize with A. delamateri.

15. Southern Sinagua petroglyphs in close proximity to Agave verdensis. 16. Agave verdensis in all its glory.

26 Author Copy CACTUS AND SUCCULENT JOURNAL 17. Agave yavapaiensis from the Verde Valley. Agave yavapaiensis is similar to A. verdensis in regard to locality and size, but features a more open rosette, and more leaves, which are a bit longer and narrower (Fig. 17). We have found it growing with A. verdensis, A. delamateri, and A. phillipsiana, but the vast majority of plants are found in two small areas of the Verde Valley. It is very, very rare, and at high risk of extinction, primarily from development, perhaps dur- ing our lifetime. Unfortunately, since A. yavapaiensis and other Arizona domesticated Agaves are consid- ered anthropogenic cultivars, they are exempt from protection under the US Endangered Species Act. Like A. verdensis, this Agave produces small quan- tities of seed in the upper one fourth of its inflores- cence (Fig. 18), and is associated with southern Sina- gua Native Americans.

Agave parryi, the very first entry of our Arizona Agave catalog, is now added to our list of domesti- cated Agaves as the final entry, as well. As a point of emphasis, this is absolutely a naturally occurring Agave, rather than a pre-Columbian cultivar, but we have come across quite a few apparently unnatu- ral A. parryi populations southeast of Tucson in the Sonoita region (Fig. 19), and more yet further north in the Mazatzal Mountains and the Verde Valley. Pre- 18. Agave yavapaiensis in its favored grassland sumed domestic A. parryi sites in the Sonoita region habitat.

2018 VOLUME 90 NUMBER 1 Author Copy 27 19. Presumed domesticate patch of var. huachucensis SE of Tucson.

all appear to consist of a single large, green clone of To anyone visiting Arizona, take a day and drive the var. huachucensis persuasion. up into the mountains where tall, glorious Agave So it seems ancient Hohokam, Salado, and Sin- stalks dot the landscape. There is something abso- agua Native Americans were quite fond of A. parryi, lutely magical about gardens planted and nurtured by and planted out plots in nearby gardens and farms, Gaia herself. And if you’re really lucky, you may hear at lower elevation than that at which it naturally the whispers of ghosts, still tending Agave gardens occurs (Parker et al 2014). We have on occasion found originally planted centuries ago. A. parryi growing in a domestic setting alongside A. If you have any questions or comments pertinent delamateri. to this article, which you would like to direct toward the author, I am available at [email protected], and Final Thoughts the online discussion forum, Agaveville.org. Please feel free to stop by and share your queries and insights. I’ll conclude by noting that in addition to our named pre-Columbian cultivars, there appear to be

several other potential candidates, which may increase References our number of recognized taxa in the future. Unfor- Howard S. Gentry (1982) Agaves of Continental North America. University tunately, there are not a lot of these plants, such that of Arizona Press. Wendy C. Hodgson (2001). Taxonomic Novelties in American Agave flower collection and proper analysis may take years (Agavaceae) Novon 11, 410–416. before sufficient data is available to reliably describe Hodgson, W.C. & A.M. Salywon: (2013) Two new Agave species (Agava- ceae) from central Arizona and their putative pre-Columbian domesti- and add to our catalog. The work continues. cated origins; Brittonia 65: 5–15. I sincerely hope you enjoyed this tour as much as Hodgson, W.C. & Slauson, L. (1995) Agave delamateri (Agavaceae) and its I enjoyed accumulating the information. My time in roles in the subsistence patterns of pre-Colombian cultures in Arizona. Haseltonia 3, 130–140. habitat has been and continues to be a highlight of Gary P. Nabhan (1995) my existence, and I can no longer imagine life without Parker K.C., Trapnell D.W., Hamrick J.L. & Hodgson WC (2014). Genetic and morphological contrasts between wild and anthropogenic popula- that connection. I highly recommend the experience tions of Agave parryi var. huachucensis in south-eastern Arizona. Annals to anyone who loves these plants. of Botany 113(6): 939–952.

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