Howell's Pussytoes - Antennaria howellii
Antennaria neodioica, Antennaria neglecta var. attenuata
(see State Rank Reason below)
MNPS Threat Rank
State Rank Reason (see State Rank above)
Antennaria howellii and Antennaria neglecta occur in Montana, but are difficult to separate (Bayer in FNA 2006; Giblin et al. [eds.] 2018). Antennaria howellii is derived by hybridization of four or more species (A. neglecta, A. plantaginifolia, A. racemosa, A. virginica, and perhaps A. marginata) (Bayer in FNA 2006; Giblin et al. [eds.] 2018). Antennaria neglecta, in the strict sense, is not a hybrid, but is a sexual diploid species (Bayer in FNA 2006; Giblin et al. [eds.] 2018). Distinguishing populations of Antennaria howellii (primarily an apomictic polyploid hybrid) from Antennaria neglecta (which have not hybridized) requires scrutinizing a population for the presence and abundance of male plants which is very challenging. Collectively the species are common in Montana and a conservation status rank of S5 has been assigned to Antennaria howellii.
PLANTS: Perennial, herbaceous forbs that produce stolons (creeping stems that grow on the ground’s surface). Plants are 5-20 cm tall. Populations either have staminate (male) and pistillate (female) plants in equal frequency or have no staminate plants. Source: Bayer in FNA 2006.
LEAVES: Basal leaves are 1-3 nerved, spatulate in shape, 15-20 mm long, 4-6 mm wide, and tipped with a short, sharp, and slender point (mucronate). Upper side of basal leaves are gray-tomentose while their lower side is gray-glabrous with white-wooly margins. Cauline leaves are linear, 7-16 mm long, and with acute tips that are not flagged (not discolored, twisted, and scarious extensions of the leaf tip). Source: Bayer in FNA 2006.
INFLORESCENCE: 5-8 flowers heads are in a corymbiform arrangement. Staminate (male) flower heads have involucres of 4.5-7 mm tall. Pistillate (female) flower heads have involucres of 5-7(-9) mm tall. Involucral bracts (phyllaries) are relatively wide and distally white with acuminate apices. Staminate corollas are 3- 5 mm long. Pistillate corollas are 4.5-6.5 mm long. Source: Bayer in FNA 2006.
Antennaria howellii and Antennaria neglecta are combined into an expanded concept using the older name (Antennaria neglecta) in the Manual of Montana Vascular Plants (Lesica et al. 2012).
Flowering during summer (Bayer in FNA 2006).
For identifying Antennaria species, it is important to note (Bayer in FNA 2006):
* the presence or absence of male plants in a population,
* if the population is mat-forming due to the presence of stolons,
* if well-developed stolons root at their tips or not, and
* the presence or absence of ‘flags’ on the tips of mid- and upper-stem leaves. Flags are flat, linear, scarious appendages of the leaf tips. Flags are not to be confused with subulate or blunt leaf tips which are basically green and herbaceous.
In Montana, two subspecies of Antennaria howellii are reported (Lesica et al. 2012).
The MTNHP is not tracking these varieties, but will retain within the botany database the subspecies name if provided by the observer.
Subspecies howellii has basal leaves that are completely glabrous on their upper surface and have been found in northwest Montana.
Subspecies neodioica (synonym ssp. petaloidea) has basal leaves that become nearly glabrous with age.
YT to QC south to CA, UT, CO, OK, KY, and SC (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Grasslands, woodlands, and open forest in the plains, valleys, and montane zones of Montana (Lesica et al. 2012). Moist forests, slopes, tops of ridges under Douglas-fir, Ponderosa Pine, Engelmann spruce, or Gambel Oak trees, and in forest openings (Bayer in FNA 2006).
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus pensylvanicus
(Colla and Dumesh 2010).
- Literature Cited AboveLegend: View Online Publication
- Colla, S.R. and S. Dumesh. 2010. The bumble bees of southern Ontario: notes on natural history and distribution. Journal of the Entomological Society of Ontario 141: 39-68.
- Flora of North America Editorial Committee. 2006. Flora of North America North of Mexico. Vol. 19. Magnoliophyta: Asteridae, part 6: Asteraceae, part 1. Oxford Univ. Press, New York. xxiv + 579 pp.
- Giblin, David E., Ben S. Legler, Peter F. Zika, and Richard G. Olmstead (editors). 2018. Flora of the Pacific Northwest: An Illustrated Manual. Second Edition. University of Washington Press in Association with Burke Museum of Natural History and Culture, Seattle, Washington. 882 pp.
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.