Curlycup Gumweed
Grindelia squarrosa
- Native to:
- Canada, Mexico, United States
iNaturalist: © holdenfrey13 (iNaturalist #92611594)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Asteraceae
- Genus:
- Grindelia
- Species:
- Grindelia squarrosa
- USDA Symbol:
- GRSQ
Growth Characteristics
- Life Cycle:
- Annual | Biennial | Perennial
- Growth Habit:
- Forb/herb
- Height:
- 90 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- jun,jul,aug,sep,oct
- Bloom Colors:
- yellow
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★☆☆☆☆ Documented Lepidoptera association (GBIF)
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Keystone Species Ranking
- Pollen Specialist Bee Keystone:
- ★★★★★ Native pollen specialist bee species supported by this genus (NWF)
Host Plant for Caterpillars
Phaneta grindeliana, Schinia mortua, Spotted Straw Moth (Heliothis phloxiphaga)
Reported Fauna Sightings
Bees: American bumble bee (Bombus pensylvanicus), Brown-belted bumble bee (Bombus griseocollis), Common eastern bumble bee (Bombus impatiens), Hunt's bumble bee (Bombus huntii), Red-belted bumble bee (Bombus rufocinctus), Southern plains bumble bee (Bombus fraternus), Two-form bumble bee (Bombus bifarius) Moths:Schinia mortua
Garden & Ecology Notes
- Wildlife Value:
- bees, butterflies, birds
- Deer Resistant:
- Yes
- Salt Tolerant:
- Yes
- Fragrant:
- Yes
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Resprouts from root crown following fire; common in disturbed and post-fire prairie sites.
Soil Requirements
- Soil Type:
- sandy, well-drained, nutrient-poor soil
- pH:
- 6.0 - 8.0 (neutral to slightly alkaline)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- commonly found in disturbed areas and prairies
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–28 days
- Notes:
- Seeds germinate readily with light; cold stratification improves germination rates but is not always required.
The above propagation data sourced from Claude AI
Pre-treatment: Seeds are placed in cold moist stratification for 60 to 90 days. Seeds are imbibed in water for 4 hours and placed in fine mesh bags buried in moist peat moss in ventilated containers under refrigeration at 1 to 3C.
Establishment: Germination was greater in light than dark. Seeds are collected in late August to late September. Seeds are grey at maturity. Seeds are collected in paper bags and kept in a well ventilated drying shed prior to cleaning.
Source: npn.rngr.net
ORGHPS Germination Guide: Sow @ 10C.