In order to verify the characteristics of Brodiaea jolonensis, I went to Monterey County, California. The trail to Junipero Serra Peak (northwest of Jolon) passes through a meadow of grassland, bordered by a marshy creek. During the hot month of early June 2004, the brodiaeas were still in bloom among the grasses and sedges near the creek. The flowers were noticeably smaller than Coastal BTK in San Diego County. The maximum length of B. jolonensis from the base of flower (at junction with pedicel) to the tip of the perianth lobe was about 2.0 cm, compared with 2.5 cm for Coastal BTK in San Diego County. Apparently the polyploid chromosome numbers of Coastal BTK and Montane BTK are reflected in the larger flower size of these populations. Scapes of B. jolonensis were 7-30 cm tall, with an average height of 16 cm. Pedicels were 2-9 cm, with an average length of 4.8 cm. The average filament length was about one mm, shorter than Coastal BTK. The anthers appeared connivent (clustered together but not organically united), unlike the separate anthers of Coastal BTK observed in coastal San Diego County. In addition, the anther tips of many flowers were incurved, obscuring the V-shaped notch in the connective tissue. Characteristics of B. jolonensis along Junipero Serra trail are summarized in Table 1. With the exception of pedicel length, the dimensions for B. jolonensis along Junipero Serra trail were similar to the comparison chart for B. jolonensis vs. Coastal BTK in Table 2.

The ovaries of B. jolonensis along Junipero Serra trail were distinctly purple, unlike the green ovaries of Coastal BTK in San Diego County. In addition, the V-shaped notch in the anther connective was entire (without a minute appendage or lobe), unlike many of the Coastal BTK examined in San Diego County. The B. jolonensis observed in Monterey County are obviously different from populations of Coastal BTK observed in San Marcos, Kearny Mesa and Otay Mesa in San Diego County. In conclusion, compared with Coastal BTK and Montane BTK, the scapes of B. jolonensis are taller, the flower dimensions are smaller, the ovaries are distinctively purple rather than green, and the V-shaped anther connectives are entire without minute lobes.

The specific epithet "jolonensis" commemorates the extinct town of Jolon (ho-LONE) in southern Monterey County. [The correct pronunciation of jolonensis is ho-lo-nen-sis.] All that remains of Jolon today are the crumbling adobe walls of the old Dutton Hotel. In 1876, Jolon was a thriving town serving the Los Burros Gold Mines, surrounding ranches, and weary highway travelers. With the completion of the Southern Pacific railroad connecting King City with Paso Robles in the late 1800s, travelers began following a different route. The famous Dutton Hotel eventually went out of business and the town of Jolon became extinct.

During June 2004, a population of Montane BTK was in full bloom in a burned meadow along Sunrise Highway in the Laguna Mountains of San Diego County. The peduncles ranged from 3 - 10 cm, with an average length of 6 cm. Pedicels of mature flowers were 4 - 7 cm, with an average length of 6.2 cm. Stamen filaments were 2 -3 mm, with an average length of 2.5 mm. In most of the flowers examined, there was no proliferation of the anther connective tissue into a dentate appendage within the apical notch. All of the ovaries were light green without a trace of purple. The flowers were 3 - 3.5 cm long, from base of flower to tip of perianth lobe. Most of the flowers were at least one cm longer than B. jolonensis in Monterey County. The staminodes were erect and inrolled along margins. They did not have the characteristic hooded apex of populations of Coastal BTK in San Diego County.

It is interesting to note that in Chis Pires' treatment of the genus Brodiaea in Flora of North America On-line, the dentate anther connective tissue is not used in the separation of Brodiaea jolonensis from B. terrestris. Scape lengths at the extreme ends of the scale would fit B. terrestris; however, the scape length for B. jolonensis is completely within the range of B. terrestris.

Although there are overlapping dimensions, when applied to the population of Brodiaea in San Marcos (previously labeled B. jolonensis), the characteristics in Table 2 fit Coastal BTK better than B. jolonensis. This is true even if the term "dentate" anther connective is not used. Some populations of Brodiaea jolonensis previously cited for San Marcos, Kearny Mesa and Otay Mesa in coastal San Diego County appear to be misidentified.

According to T. F. Niehaus (personal communication, 2004), hybrids are encountered where the distribution of two Brodiaea species overlap. The hybrids show a range of intermediate characteristics between the parents. Under controlled greenhouse conditions, Niehaus was able to hybridize every combination between all species and obtain seed. In a few crosses a relatively high percentage of seed set was obtained, although seed set was low in most interspecific crosses. He was able to grow the hybrid seeds to flowering in 2-3 years. According to Niehaus (1971), the majority of hybrids had sterile pollen. Although pollen viability is a good indicator of hybridization in brodiaeas, there may be other factors causing hybrid sterility. Hybrid clones can be propagated by cormlets.

Throughout the range of Coastal BTK and Montane BTK in southern California, small clonal populations can be found with intermediate or aberrant staminodia. I observed a small population of a variant B. elegans at Mission Trails Regional Park. The flowers appeared to be intermediate between nearby B. elegans ssp. elegans and Coastal BTK; however they had 65% pollen viability which is not typical of a true interspecific brodiaea hybrid. Another small population of Montane BTK at Cuyamaca Lake had staminodes bearing anthers at the tips. Small populations with the same aberrant staminodes may be clones of each other that developed asexually through cormlets.

In San Marcos, I have observed a brodiaea variant with intermediate characteristics between two possible parental species, Coastal BTK and B. filifolia. [A third species (B. orcuttii) also grows nearby within the vernal pools.] One of the most obvious characteristics that indicate hybridization is a structure called a staminodium that represents a sterile, nonfunctional stamen. The staminodes of the possible hybrid are intermediate between the conspicuous, petaloid staminodes of Coastal BTK and the slender (filiform), inconspicuous staminodes of B. filifolia. The variant staminodes appear strap-shaped, unlike the hooded (incurved) staminodes of typical Coastal BTK. One major caveat to the hybrid hypothesis is that I have also seen considerable variation in other brodiaea populations. On the Santa Rosa Plateau of Riverside County, populations of BTK exhibit a wide range of variation, including strap-shaped staminodes similar to the San Marcos "hybrid." Could it be that the San Marcos "hybrid" brodiaea is simply a variation within the BTK population?

The San Marcos variant appeared to be a clonal population because it occurred in a one acre area at the southwest end of the property, and probably reproduced asexually through cormlets. In May 2005, I visited this same site but did not observe any of the variants. Instead I found numerous B. filifolia, B. orcuttii and Coastal BTK. The previous winter and spring was an exceptional year for rainfall in San Diego County and brodiaea populations were plentiful. In May 2006, I found variants with strap-shaped staminodes at the northeast end of the property. The flowers were completely sterile with no pollen inside the anthers, indicative of sterile hybrids. Unfortunately, the fate of these rare brodiaea populations is dismal because of the rapid (uncontrolled) urbanization of northern San Diego County. In this case, the rare brodiaeas just happen to be living in a 40 acre field surrounded by buildings and zoned for industry.

According to Niehaus (1971), most Brodiaea species have a base number of 6 chromosomes per haploid set, while B. elegans, B. insignis and B. kinkiensis have base numbers of 8. The gametophyte number is the number of chromosomes per gamete and the sporophyte number is the number of chromosomes per adult plant cell. Brodiaea jolonensis in Monterey County has a gametophyte number of 6 and a diploid (2n) sporophyte number of 12. Niehaus (1971) also reported a B. jolonensis on Otay Mesa with a gametophyte number of 18 and a hexaploid (6n) sporophyte number of 36. The latter species appears to be Coastal BTK observed throughout San Diego County. According to Niehaus (1971), B. terrestris ssp. kernensis from Kern County has a gametophyte number of 24 (4 sets of 6 chromosomes) and a sporophyte number of 48 (octoploid). Brodiaea filifolia and B. orcuttii both have gametophyte numbers of 12 (2 sets of 6 chromosomes) and sporophyte numbers of 24 (tetraploid).

According to Niehaus (1971), the lack of quadrivalents in meiosis plus the differences in size of individual mitotic chromosomes at different ploidy levels suggests that these are "old polyploids." That is, the tetraploids, hexaploids, and octoploids have been in existence long enough to change by translocations, deletions, and so on. These differences apparently are enough to ensure that during meiosis only bivalents will occur in the higher ploidy levels. In bivalents, only two sets of maternal and paternal chromosomes associate during synapsis of meiosis, in contrast to quadrivalents where four sets of homologous chromosomes associate during meiosis.

If Brodiaea species behave as diploids, then BF and BO each have n = 12 and 2n = 24, and BTK has n = 18 or a higher number. In fact, BTK could be 2n = 36, 38, 40, 42, 44, 46, 48, etc. and still be theoretically fertile with two sets of homologous chromosomes. A hybrid between BF or BO and BTK would be sterile because of the non-homologous pairs of chromosomes that differ in number. Hybridization may occur, but the resulting hybrid offspring grown from seed may by sterile without viable pollen. For example, a cross between BF and BTK could result in a hybrid with 12 BF chromosomes and 18 BTK chromosomes which would not match up during synapsis of prophase I. This hypothesis explains the sterile hybrids we have observed in San Marcos.

Information and images presented on this page, and quantitative data and graphs compiled by Tom Chester, indicate that brodiaea populations from San Marcos, Kearny Mesa, Mission Trails and Otay Mesa in San Diego County are Coastal BTK rather than B. jolonensis. Populations from the Santa Monica Mountains and Santa Catalina Island (Los Angeles County) and the Santa Rosa Plateau (Riverside County) also appear to be Coastal BTK. In May 2006 I examed a population above Gaviota Pass in Santa Barbara County and it appears to be Coastal BTK and not B. jolonensis. In "A Biosytematic Study of the Genus Brodiaea," Univ. of Calif. Publications in Botany Vol. 60 (1971), T.F. Niehaus cites a collection of B. jolonensis (# 662) from Otay Mesa. Is this the same Coastal BTK that Tom and I have observed throughout coastal San Diego County? As of June 2005, we have been unable to locate any brodiaeas at this site, probably because of the extirpation of Niehaus' original collection site. Unfortunately, herbarium specimens do not show some of the detailed floral characteristics that distinguish B. jolonensis from Coastal BTK.

In July 2005, I examined the vascular pattern of an inner perianth segment from #662. It had 3 strands of tracheary elements per bundle, a total of nine strands. This is typical of coastal BTK populations in San Diego County. [B. jolonensis has a total of only three or four strands.] Niehaus published a sporophyte chromosome number of 36 for this specimen, compared with 12 for B. jolonensis in Monterey County and 48 for B. terrestris ssp. kernensis in Kern County. It seems likely that Niehaus' #662 may in fact be "Coastal BTK" which has been confused with B. jolonensis in southern California for decades. Niehaus also determined a chromosome number of 36 for a sample from Santa Barbara County, different from the number of 12 determined from plants in Monterey County. As of May 2006, we have determined that the plants at Gaviota Pass are Coastal BTK and not B. jolonensis. It is also possible that Montane BTK in southern California has the same chromosome number as Coastal BTK. No one has ever determined a chromosome number for any putative BTK populations except for plants in Tulare and Kern counties.

Clearly, more chromosome studies and observations are needed to determine the relationship of Coastal BTK, Montane BTK, and the populations of B. terrestris ssp. kernensis in Kern County. We are currently collaborating with Dale McNeal of University of the Pacific to get chromosome counts of a larger sample of the southern California plants.

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