Fall-Blooming Marin Tarplants

by Doreen Smith

The following are the Marin genera of the group of the Asteracea that includes tarplants;
Anisocarpus, Achyrachaena, Calycadenia, Centromadia, Deinandra, Hemizonia,
Holocarpha, Holozonia, Lagophylla, Layia, and Madia.

Some of those that can seen in bloom well into Fall are in the following selection;

Calycadenia, rosinweed, tackstem,
Two species are definitely present, Calycadenia multiglandulosa on serpentine,
and Calycadenia truncata on volcanics..

Centromadia, Spikeweed
Two species are present, Centromadia fitchii and Centromadia pungens
These usually grow on disturbed ground such as roadsides.

Deinandra, fragrant tarplant
One species, Deinandra corymbosa, grows on sandy soils in both east and west Marin.

Hemizonia, tarplant
One species, with two subspecies
Hemizonia  congesta ssp. congesta, is rare, and grows in Tomales area mostly. and Hemizonia congesta ssp. lutescens. is common, and has both a Spring and a Fall race.

Holocarpha, tarplant
Two species, one is very rare or extirpated here , Holocarpha macradenia, and the other is
Holocarpha virgata found at Lagunitas Meadows, MMWD property.

Holozonia, white crown,
One species, Holozonia filipes, grows in summer-dry streambeds in Rock Spring meadow.

Madia, common tarplant
Five species. only two of which are likely to remain in bloom in Fall
Madia elegans, and Madia sativa.

Photos by Doreen and Vernon Smith.