Plants of Southern California: Agoseris retrorsa, A. grandiflora, and their hybrid


Table of Contents

Introduction
Distinguishing Characteristics
Geographic Distribution of These Taxa in the Cuyamaca Mountains


Fig. 1. Young plants of Agoseris retrorsa and A. grandiflora growing together in Cuyamaca Rancho State Park along the Azalea Spring Trail on 28 May 2021. Even these young plants show well the typical difference between these species in their leaf shapes. A. retrorsa has a narrow leaf rachis, with deep lobes that are pointed backward. A. grandiflora has a wider leaf, generally entire or with very shallow lobes, but sometimes with deeper lobes that are not pointed backward; see Fig. 3.

Note that a leaf from an unlabeled A. retrorsa extends through the base of the labeled A. grandiflora.

Click on the picture for a larger version.

Fig. 2. Mature plants of A. retrorsa (left) and A. grandiflora (right). Two extreme forms of A. grandiflora are shown, one with very wide, entire leaves (top right), and one with mostly lobed leaves (bottom right). A. retrorsa has no such extreme variation. The two examples shown look very similar.

Click on the pictures for larger versions.

Fig. 3. Closeup of a typical leaf of A. retrorsa (top); a leaf of the hybrid between A. grandiflora and A. retrorsa (middle); and one of the most lobed leaves of A. grandiflora (bottom).

Click on the pictures for larger versions.

Introduction

Distinguishing Characteristics

Geographic Distribution of These Taxa in the Cuyamaca Mountains



Go to:


Copyright © 2021 by Tom Chester and Jim Roberts
Permission is freely granted to reproduce any or all of this page as long as credit is given to us at this source:
http://tchester.org/plants/analysis/agoseris/grandiflora_retrorsa.html
Comments and feedback: Tom Chester
Last update: 31 May 2021