R. Fraley

Powdery Shield

Physcia millegrana

A compact cluster of Powdery Shield (Physcia millegrana) occupies the center of the bark ridge, its tiny lobes coated in fine soredia. The surrounding species sharpen its identification: bright Common Sunburst to the left provides vivid contrast, while the broad, pale-green lobes of Eastern Speckled Shield at right emphasize the minute scale and powdery texture that distinguish P. millegrana in mixed lichen communities. Powdery Shield Lichen is one of Minnesota’s most common small foliose lichens, recognized by its soft, powder-dusted surface and compact growth form. Its fine soredia give the thallus a matte, frosted look that distinguishes it from darker, more textured Physcia relatives.

For identification details and comparison with other similar species, see the Physcia millegrana in the Field Notes section.

Powdery Shield Among Sunburst and Speckled Shield Powdery Shield Among Sunburst and Speckled Shield
Tiny, dusted lobes revealing the fine-scale texture that defines Powdery Shield.
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 200 • Aperture f/13.0 • Shutter 3.2 s
E21A8088A • Size: 1683x1122

Candleflame with Powdery Shield and Mealy Shadow Candleflame with Powdery Shield and Mealy Shadow
Powdery Shield in different color environments, set against both warm and cool companions.
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 200 • Aperture f/13.0 • Shutter 5 s
E21A8057 • Size: 2208x1472

Powdery Shield and Candleflame on twig Powdery Shield and Candleflame on Twig
Dust-gray rosettes rising above a bright cushion of Candleflame on a red maple twig.
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 400 • Aperture f/5.6 • Shutter 1/250 s
E21A1081 • Size: 5112×3410

Candleflame and Powdery Shield on Elm Bark Candleflame and Powdery Shield on Elm Bark
A multi-species bark mosaic built from warm and cool tones, with Powdery Shield’s gray rosettes among Mealy Shadow and Candleflame.
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 200 • Aperture f/9.0 • Shutter 2.5 s
E21A8051–8055 • Size: (see original)

Powdery Shield in a Bark Crevice Powdery Shield in a Bark Crevice
A pale rosette with rimmed apothecia, framed by bright Candleflame.
Camera: Canon EOS 5D Mk IV
Lens: EF100mm f/2.8L Macro IS USM
Settings: ISO 200 • Aperture f/13.0 • Shutter 2.5 s
E21A8187 • Size: (see original)