Butterfly of the Week

Horace's Duskywing

Erynnis horatius (Scudder and Burgess 1870)

Status: Uncommon breeding resident.

Flight: Apparently triple brooded in Iowa, with the first brood flying from late April to early May, the second from early June to late July, and the third from mid August to early September.

Distinguishing features: Erynnis horatius is close to E. juvenalis in appearance but is more uniformly brown and lacks the two sub apical pale spots on the lower hind wing. Most of its flight occurs during the summer months, long after E. juvenalis has passed. Both of these species are larger than E. baptisiae and E. lucilius. Wingspan: 3.5-3.8 cm.

Distribution and habitat: Map 92. Scattered and rare throughout the state. No clear habitat preferences have been noted; it has been encountered from a wide variety of natural and altered habitats. In western Iowa it may be more common along oak-lined stream corridors.

Natural history: Although E. horatius has a wide distribution in the United State, Don C. MacNeil (in Howe 1975: 525) notes that it is "almost absent from the Great Plains." Its large have been reported to eat various oak species.

Questions: Why is E. horatius so much more uncommon in the state that E. juvenalis? What are its preferred habitats, if any? Is it more mobile that E. juvenalis?

The Butterflies of Iowa, by Dennis W. Schlicht, John C. Downey, and Jeffrey C. Nekola

University of Iowa Press Announces New Laminated Guide

Attention rock collectors, hunters, and lovers of all things mineral! The University of Iowa Press is pleased to announce the release of our newest Bur Oak Guide--Iowa Gems and Minerals in Your Pocket by Paul Garvin and Anthony Plaut!


From the spiky teeth of a geode containing sparkling quartz crystals, the rich browns and golds of smoky quartz and goethite needles on calcite, and the coral-like branches of plumose barite to the abstract reds and whites of polished agate cabochons, world-class mineral crystals are harvested from the rocks of the Hawkeye State. Collecting these high-quality crystals requires access to active mines, pits, and quarries, and individual collectors are rarely allowed entrance to these facilities. With information about each specimen’s type, source, size, and current location, Paul Garvin and Anthony Plaut’s Iowa Gems and Minerals in Your Pocket provides access to the glittering, gleaming world of Iowa crystals.


Order your copy today!

To the folks in Austin, Texas who commented on June 1

Thanks so much for your question:

"We live in Austin Texas and have planted our yard with Buffalo grass. What are the long, tough shoots in the grass? Are they weeds or seeds? We have been trying to kill them, but they are everywhere. Are they normal?"

Unfortunately this is out of our range; a good resource to check with is the Iowa State University Herbarium folks. Good luck!

Plant of the Week

Sand reed
Calamovilfa longifolia (Hook.) Scribn.
other common names: prairie sandreed
Calamovilfa: from Greek calamos, a reed, and vilfa, an early name applied to a genus of grasses
Longifolia: meaning “long leaves”
Grass family: Poaceae (Gramineae)

Photograph by Thomas Rosburg, Wildflowers of the Tallgrass Prairie: The Upper Midwest, Second Edition