Is it deer resistant?

Yes

Field Thistle is deer resistant.

Cirsium discolor

Deer: Rarely
Height: 10 ft (3 m)
Spread: 2 ft (61 cm)
Zones: 3–10
Light: Full sun

Biennial
Perennial
Wildflower

Field Thistle (Cirsium discolor)

Photo: USGS Bee Inventory and Monitoring Lab from Beltsville, Maryland, USA · Public domain

Perennial Cirsium

More details

Light: Full sun, Partial shade
Water: Low
Type: Biennial, Perennial, Wildflower
Maintenance: Low
Growth: Medium
Bloom: Fall, Summer
Features: Flowering, Native
Best uses: Meadow, Naturalized

More in Cirsium