# Woollypod Milkweed (Asclepias eriocarpa)

> A stout, woolly, cream-flowered California milkweed of dry hillsides and roadsides, with thick whorled leaves and densely hairy pods. Historically the most important fiber plant of several California Indigenous nations.

Source: https://milkweedusa.com/species/woollypod-milkweed/  
Licence: CC BY 4.0 (Milkweed USA)

## Summary

A stout, woolly, cream-flowered California milkweed of dry hillsides and roadsides, with thick whorled leaves and densely hairy pods. Historically the most important fiber plant of several California Indigenous nations.

## Key facts

| Field | Value |
| --- | --- |
| Scientific name | Asclepias eriocarpa Benth. |
| Genus | Asclepias |
| Family | Apocynaceae |
| Common names | Woollypod Milkweed, Indian Milkweed, Kotolo |
| Status | Native |
| Height | 2 ft–4 ft |
| Spread | 1.5 ft–3 ft |
| Flower color | cream, white |
| Bloom period | May to August |
| Light | Full sun |
| Soil moisture | Dry |
| USDA zones | 7-10 |
| Leaf arrangement | whorled |
| Leaf shape | oblong |
| Sap | Milky latex |
| Root system | Rhizomatous, spreads by root |
| Seed stratification | 30 days cold-moist |
| Monarch value (0-5) | 4 |
| Garden value (0-5) | 3 |
| Nectar value (0-5) | 3 |
| US states recorded | California, Nevada |

## Identification

- Thick, wavy-edged leaves usually in whorls of three or four.
- Dense clusters of cream-white flowers with a waxy look.
- Pods conspicuously covered in white wool.

## Ecology

A major western monarch host across California’s interior valleys and foothills, and unusually high in cardenolides, which gives its larvae strong chemical defense.

## Growing

Drought-tolerant and long-lived, but coarse. Best in wilder parts of a California garden.

## Cautions

One of the most toxic North American milkweeds to livestock.

## References

- Plants of the World Online: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:94258-1
- GBIF: https://www.gbif.org/species/3170253
- iNaturalist: https://www.inaturalist.org/taxa/58796
- Wikipedia: https://en.wikipedia.org/wiki/Asclepias_eriocarpa
- BONAP county map: https://bonap.net/MapGallery/County/Asclepias%20eriocarpa.png
- NatureServe: https://explorer.natureserve.org/Search?searchTerm=Asclepias%20eriocarpa

## Photographs

- Woolypod milkweed (Asclepias eriocarpa) (27117131095) (Pacific Southwest Region USFWS from Sacramento, US, Public domain): https://commons.wikimedia.org/wiki/File:Woolypod_milkweed_(Asclepias_eriocarpa)_(27117131095).jpg
- J20160707-0135—Asclepias eriocarpa-w Apis mellifera—RPBG (27695833984) (John Rusk from Berkeley, CA, United States of America, CC BY 2.0): https://commons.wikimedia.org/wiki/File:J20160707-0135%E2%80%94Asclepias_eriocarpa-w_Apis_mellifera%E2%80%94RPBG_(27695833984).jpg
- H20140611-2884—Asclepias eriocarpa—RPBG (14445162271) (John Rusk from Berkeley, CA, United States of America, CC BY 2.0): https://commons.wikimedia.org/wiki/File:H20140611-2884%E2%80%94Asclepias_eriocarpa%E2%80%94RPBG_(14445162271).jpg
- H20140611-2881—Asclepias eriocarpa—RPBG (14425400016) (John Rusk from Berkeley, CA, United States of America, CC BY 2.0): https://commons.wikimedia.org/wiki/File:H20140611-2881%E2%80%94Asclepias_eriocarpa%E2%80%94RPBG_(14425400016).jpg
- J20170706-0075—Asclepias eriocarpa w Apis mellifera—RPBG—DxO (35098012733) (John Rusk from Berkeley, CA, United States of America, CC BY 2.0): https://commons.wikimedia.org/wiki/File:J20170706-0075%E2%80%94Asclepias_eriocarpa_w_Apis_mellifera%E2%80%94RPBG%E2%80%94DxO_(35098012733).jpg
- Asclepias eriocarpa kz01 (Krzysztof Ziarnek, Kenraiz, CC BY-SA 4.0): https://commons.wikimedia.org/wiki/File:Asclepias_eriocarpa_kz01.jpg
- Woollypod milkweed plant (15813704011) (Pacific Southwest Region USFWS from Sacramento, US, Public domain): https://commons.wikimedia.org/wiki/File:Woollypod_milkweed_plant_(15813704011).jpg
- Asclepiaseriocarpa (Anthony Valois, Public domain): https://commons.wikimedia.org/wiki/File:Asclepiaseriocarpa.jpg

## How to cite

Milkweed USA. (2026). Woollypod Milkweed (Asclepias eriocarpa). https://milkweedusa.com/species/woollypod-milkweed/