Summary
A study was conducted to determine conditions promoting high levels of seed germination of 23 native tallgrass prairie forb species collected from the Sioux Prairie (160 acres) in South Dakota (USA). Species which would be useful in prairie restorations were selected.
Seed was collected by hand in spring, summer and autumn. All filled seeds were tested for viability (soaking for 8 h in 0.1% triphenyl tetrazolium chloride (TCC)). Species investigated and viability (%) was:
Yarrow Achillea millefolium (100)
wild onion Allium spp. (100)
Lead plant Amorpha canescens (92)
Thimbleweed Anemone cylindrica (98)
Pasque flower Anemone patens (98)
Antennaria spp. (97)
Silky aster Aster sericeus (100)
Canadian milkvetch Astragalus canadensis (96)
Groundplum milkvetch Astragalus crassicarpus (100)
Spotted cowbane Cicuta maculata (100)
Purple coneflowerEchinacea angustifolia (100)
Prairie fleabaneErigeron strigosus (not tested)
Prairie gentianGentiana puberula (92)
Prairie smoke Geum triflorum (100)
Meadow blazing-starLiatris ligulistylis (weevil infested)
Dotted blazing-starLiatris punctata (weevil infested)
Wood lily Lilium philadelphicum (98)
Wood betony Pedicularis candensis (58)
prairie cloverPetalostemum spp. 100)
Tall cinquefoilPotentilla arguta (100)
Mexican hatRatibida columnifera (100, after puncture treatment)
Smooth ironweed Vernonia fasciculuta (100)
alexanders Zizia spp. (100)
A 'normal’ germination treatment was undertaken on moist filter paper in petri dishes and comprised four replications (25 seeds/replicate). Additional seeds from species which failed to germinate using this technique were subjected to other methods (e.g. moist-cold, scarification) to break dormancy.
Of the 23 species of seeds tested, 69.5% germinated under normal conditions, 21.7% required moist-cold treatment, 4.4% required scarification, and 4.4% never germinated.