Family: Asteraceae — aster family

Most members of the aster family in New England are annual or perennial herbs. They have a unique type of inflorescence consisting of many tiny flowers aggregated together in a flower head (a capitulum) that forms a false "flower." The individual flowers can be one of several types. The most common types of flowers are ray flowers (which are zygomorphic) and disk flowers (which are actinomorphic); different species may have one type or the other or both kinds in the same flower head. The base of a flower head is subtended by a number of bracts (called involucral bracts) that collectively form an involucre. Individual flowers within the flower head may have pollen-bearing or ovule-bearing parts, or both. The sepals, attached near the summit of the ovary, frequently look like bristles or scales, and collectively are called the pappus. The ovary is comprised of 2 united carpels that usually have styles cleft in 2. The stamens are attached to the petals and usually have long anthers united into a tube. The fruit is a specialized type of achene called a cypsela.

Leaves: Acanthospermum australe. ~ By Kim Starr. ~ Copyright © 2024 CC BY 3.0. ~ starrimages[at]hear.org ~ Plants of Hawaii - www.hear.org/starr/images/?o=plants

Plant form: Acanthospermum australe. ~ By John Kunzer. ~ Copyright © 2024 University of South Florida. ~ Requests for image use not currently accepted by copyright holder ~ Atlas of Florida Vascular Plants - florida.plantatlas.usf.edu/Default.aspx

This family’s genera in New England

Visit this family in the Dichotomous Key

Getting Started

If you're not sure what to do from here, take a look at this Help page for instructions.

Help

Shortcut to plant groups

If you already know what group your plant is in, start with this shortcut to find your plant more quickly.

Map to groups