This at Lava Bluffs Trail near 4000 foot level . Here is the underside of a frond .
This fern was growing on a partially shaded cut bank within the context of a mixed oak woodland not far from the main trail. The narrowness of the leaves, especially proximal, are clearer in image 2, which also displays the sporangia.
This fern was seen on a shady bluff, growing among other fern taxa and various rock outcrops. Image two depicts the underside of a frond as the upper part of the image.
Growing out the side of a large wet rock outcrop. It's P. imbricans because of its small size and because the bracts on the stem of the leaf are small.
Polystichum imbricans is a species of fern known by the common name narrowleaf sword fern. It is native to western North America from British Columbia to southern California, where it grows in rocky habitat in coastal and inland mountain ranges and foothills. This fern produces several erect linear or lance-shaped leaves up to 80 centimeters long. Each leaf is made up of many narrow, overlapping, sometimes twisting leaflets each 2 to 4 centimeters long. The leaflets...