Notholaena californica
California cloak fern
California cloak fern
Fig. 1. not supplied yet
Notholaena californica, California cloak fern, is very similar to, and often mistaken for, Pentagramma triangularis, goldback fern. Both ferns have similar-shaped leaves, with whitish or yellowish exudate on the bottom surface. There are four main characteristics that distinguish these two genera which are illustrated in Fig. 2.
- The leaf edges for Pentagramma are only turned-down ~90°, whereas the leaves of Notholaena are rolled completely over, turning an angle of ~180°. They do that to cover the sporangia.
- The ultimate leaflets for Pentagramma are U-shaped, with rounded tips, whereas the ultimate leaflets for Notholaena are V-shaped, with more of a pointed tip.
- The ultimate leaflets for Pentagramma touch the leaf rachis (midvein) on both edges, whereas the ultimate leaflets for Notholaena only touch the leaf rachis on the upper edge, with the lower edge some distance away from the rachis.
- If you have a fertile leaf, the sporangia of Pentagramma are scattered throughout the back of the leaflet, following the veins of the leaflet, as seen in Fig. 2, whereas the sporangia of Notholaena are hidden under the turned-over leaflet margin until the spores emerge.
Fig. 2. Differences between the leaf of Pentagramma, shown at left, and the leaf of Notholaena, shown at right.
Pictures of the bottom of the leaves
The Jepson Manual Second Edition Notholaena californica description says that there are two separate taxa of this species, one with white exudate on the leaf bottom side, var. leucophylla, and one with "pale to bright yellow" exudate, var. californica.
After seeing a leaf with bright white exudate in lower Tahquitz Canyon on 6 April 2011, I had thought these two entities were very clearly visually distinct in the field. But after viewing and processing the pictures in Figs. 2 and 3, I am now not so sure about how easy it is to distinguish them.What really surprised me in processing these pictures is that the processing can significantly change the color! Fig. 3 shows three pictures that are the exact same picture, just processed differently!
Fig. 4 shows pictures from various locations arranged from the brightest yellow to the brightest white, including the pictures in Fig. 3.
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| Fig. 3. The same picture of the leaf bottom of Notholaena californica showing variation in the color of the exudate resulting from the processing of the picture. The photograph is from Borrego Palm Canyon on 31 January 2010. Click on the pictures for larger versions. | ||
Henderson Canyon, 12/29/08 | 
Henderson Canyon, 12/29/08 | 
Borrego Palm Canyon 1/31/10 |
Borrego Palm Canyon 2/15/10 |
Agua Caliente County Park, 12/23/09 | 
Agua Caliente County Park, 12/23/09 | 
Borrego Palm Canyon 1/31/10 | 
Borrego Palm Canyon 1/31/10 |
Flat Cat Canyon, 2/20/15 |
Borrego Palm Canyon 2/15/10 | 
PCT north of SR78 10/12/13 | 
PCT north of SR78 10/12/13 |
Borrego Palm Canyon 1/31/10 | 
Lower Tahquitz Canyon 4/6/11 |
Borrego Palm Canyon 2/15/10 | |
| Fig. 3. Leaf bottoms of Notholaena californica from various locations, arranged in order of the apparently color of the exudate, from the brightest yellow to the brightest white. Three pictures surrounded by yellow are the same picture just processed differently. Click on the pictures for larger versions. | |||
James Dillane and Keir Morse both independently suggested that a color scale in the picture is strongly needed, so on 25 February 2015 I took pix using both white- and yellow-colored envelopes in the picture. Furthermore, Keir suggested that the leaf underside color may depend on age, so I photographed both a newer and older leaf. For example, once the spores appear, they cover up some of the exudate and change the apparently color from a distance; see photo from Borrego Palm Canyon from 31 January 2010.
Pictures from 25 February 2015 are given in Figs. 5 through 8.
Fig. 5. Notholaena californica plant from Henderson Canyon 25 February 2015 whose leaves are shown in the following figures. Click on the picture for a larger unlabeled version.
Photographed in field in sunlight against a white background. | 
Photographed in field in sunlight against a dark gray background of the screen of my GPS unit. | 
Photographed two days later inside my house with bright sunlight through a sliding glass door. | 
Photographed two days later inside my house with bright sunlight through a sliding glass door with camera flash. |
| Fig. 6. Photograph of the underneath of the sampled leaf tip of a younger leaf shown in Fig. 5. Each picture was photographed in different illumination and/or with a different background, as labeled below each picture. Click on the pictures for larger versions. | |||
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| Fig. 7. Left: Photograph in the field in sunlight with a white and yellow envelope background. Right: Photograph two days later inside my house with bright sunlight through a sliding glass door with the same background that also includes an older leaf portion. Click on the pictures for larger versions. | |||
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| Fig. 8. Photographs two days later inside my house using flash. Left: Photograph with a white envelope background. Right: Photograph with a yellow envelope background. Click on the pictures for larger versions. | |||
Most of these pictures fairly clearly show that the underneath of the fresher leaf definitely is yellowish, even though a picture from the field of a neighboring fresh leaf appears to show a mostly-white underneath. Pictures from the field of a leaf on the plant are always taken in fairly heavy shade, which apparently conspires to create a picture with a mostly-white underneath.
I thank James Dillane, Keir Morse and Jane Strong for comments on this page.