Plants of Southern California: Arctostaphylos parryana ssp. desertica Inflorescences
This page shows some of the various forms of the inflorescence of Arctostaphylos parryana ssp. desertica, beginning with its nascent inflorescence proceeding through fruit.
Fig. 1 shows some various forms of the nascent inflorescence found on a single plant along the Santa Rosa Mountain Road that was vouchered by Keeley, and cited as a paratype in his paper defining ssp. desertica. This plant is in a distinctive location, with no other manzanita plants in its vicinity with which it could be confused.
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| Fig. 1. Various forms of the nascent inflorescence found on a single plant along the Santa Rosa Mountain Road that was vouchered by Keeley as A. parryana desertica. The four pix in the top two rows are from an iNat observation by Morgan Stickrod on 30 January 2020. The bottom left pix is from an iNat observation by Tom Chester on 17 October 2006. The bottom right pix is from an iNat observation by Tom Chester on 19 July 2021.
Click on the pictures for larger versions. Go to the original iNat observations for additional pix. | |||
Five of the six nascent inflorescences shown in Fig. 1 are similar, with flower bracts much longer than the buds, with a wide base that tapers gradually to the tip. The flower bracts in the pix in row 2 at right appear much different because they are shorter due to a less elongate tip, and because it appears the tips are early deciduous. The only obvious other difference in that inflorescence is that it has at least seven branches, whereas the others have only three branches.
Interestingly, in the Keeley paper defining this taxon, he says that this taxon has the same "reduced floral bracts" as A. parryana ssp. parryana. The floral bracts in Fig. 1 are almost identical to the ones in the pix of a plant of A. parryana ssp. parryana from the San Gabriel Mountains in Fig. 1 of Geographic Distribution of Arctostaphylos Species in the SGM. However, I wouldn't call these reduced floral bracts, since they are longer and more leaf-like than those in many Arctostaphylos species. This is in agreement with values in Table 3 in his paper, where he gives the length of the "lower bract" as "4.6" (without units) for ssp. desertica, but only "0.4" for ssp. parryana, and "6.3" for A. glandulosa, noted for its leaf-like bracts.
Fig. 2 shows the inflorescences from other plants from the San Jacinto and Santa Rosa Mountains, ordered by bloom stage.
SnJt, PCT North of SR74, by Tom Chester, 16 November 2020 | 
SnJt, Skyline Trail, by Tom Chester, 31 August 2012. | ||
SnJt, Skyline Trail, by Tom Chester, 31 August 2012. | (intentionally blank) | ||
SnJt, PCT North of Cedar Spring Trail, by Tom Chester, 8 April 2022. | 
SnJt, PCT north of Cedar Spring Trail, by Tom Chester, 8 April 2022. | ||
Santa Rosa Mountains, Santa Rosa Mountain Road, by Jeff Bisbee, 5 June 2010 | 
SnJt PCT south of road to Goff Flat, Matt Berger, 8 May 2019 | ||
| Fig. 2. Nascent inflorescences and mature inflorescences for other plants from San Jacinto Mountain (SnJt) and the Santa Rosa Mountains.
Click on the pictures for larger versions. The last two pix are from iNat observations; click on the description below each pix to go to the original iNat observation. | |||