Northern oak fern
Gymnocarpium dryopteris

Family: Cystopteridaceae

What it is like

Gymnocarpium dryopteris is a deciduous Fern growing to 0.3 m (1ft) by 0.3 m (1ft in) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 3. It is noted for attracting wildlife. Suitable for: light (sandy) and medium (loamy) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very acid soils. It can grow in full shade (deep woodland) or semi-shade (light woodland). It prefers moist or wet soil.

Height (m): 0.3

Where it is found

Shady, moist woods, streambanks and wet cliffs preferring mixed coniferous forests. It is equally likely to occur in wetlands or non-wetlands.

Widespread across much of North America and Eurasia. It has been found in Canada, the United States, Greenland, China, Japan, Korea, Russia, and most of Europe.

Conservation Status:

Countries/locations it is found in

Canada, the United States, Greenland, China, Japan, Korea, Russia, and most of Europe.

How it is used

Food

Rating: 0

Medicine

Rating: 0

Other

Rating: 3

A good medium density groundcover for a woodland garden; their lush, bright green fronds brighten a dark forest floor. Grizzly Bear and Elk have been observed eating Oak Fern. Locations: Accent: Good Texture/Form. Flower borders and beds. Ground Cover. Cottage & Informal. Garden Architectural. Massed. Wild Flower. Woodland. Cut Flower (leaf). Containers.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

Ground Cover: Ground Cover

How it is grown

A small deciduous Mat forming fern with a slender creeping rhizome, and much-divided, triangular to ovate fronds. USDA Hardiness Zones: 2 - 7. Soil pH: 4.5 - 6.4. Growth Rate: Slow to moderate. Life Span: Long. Texture: Fine. Sun: Partial Shade, Shade. Prefers a neutral to acid, leafy, moist soil, enriched with garden compost, in deep shade. Soil Type: Loamy. Soil Moisture: Moderate. Minimum Root Depth: 12 inches (30cm). Root Type: Long Rhizome. Seasonal Interest: Spring-Fall. The broadly triangular leaves are divided into 3 approximately equal primary divisions, each turned to a heavily horizontal position. Sprawling, it often shows slightly twisted leaves and leaflets. Requires cool, moist, acidic soil. Good ground cover. Drought: Intolerant. Flood: Moderate. Salt: Sensitive. Soil Compaction: Intolerant. Mowing: Intolerant. Fire Damage: Intolerant. Cold Injury: Infrequent. Disease Issues: Minor. Insect/Pest Damage: Minor. Plant Concerns: Oak fern can interfere with the growth of Engelmann spruce (Picea engelmannii) seedlings. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a runner spreading indefinitely by rhizomes or stolons. The root pattern is rhizomatous with underground stems sending roots and shoots along their length .

Propagating it: Sow spores at 15°C (59°F) when ripe or divide in spring

Best place to grow:

Habit: Fern

Hardiness: 2-7

Growth: Slow

Soil: Light (sandy), medium

Shade: Full shade, semi-shade

Moisture: Moist, wet

Things to keep in mind

Its other names

Local names

Western oakfern, common oak fern, oak fern, northern oak fern

Synonyms

Aspidium dryopteris Baumg. Carpogymnia dryopteris (L.) Á. Löve & D. Löve. Currania dryopteris (L.) Wherry. Dryopteris dryopteris Britton. Dryopteris linnaeana C. Chr. Dryopteris pulchella (Salisb.) Hayek. Dryopteris pumila V.I. Krecz. Filix pumila Gilib. G. dryopteris subsp. dryopteris. G. dryopteris var. dryopteris. Lastrea dryopteris (L.) attr. by authors to Bory. Nephrodium dryopteris (L.) Michx. Phegopteris dryopteris (L.) Fée. Polypodium dryopteris L. Polypodium pulchellum Salisb. Thelypteris dryopteris (L.) Sloss.