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SENSITIVE FERN

NOMENCLATURE

Other Names:

Scientific Name: Onoclea sensibilis L.

 Plant Family: Polypodiaceae

GENERAL INFORMATION

Botanical Description: herbaceous

 Stems: no real stems

 Leaves: Often 6 - 18 inches high. Sterile fronds are yellow-green, pinnately divided into few toothed or lobed leaflets and may reach 3 feet in length. Fertile fronds are erect, shorter than sterile fronds, twice divided pinnately, the leaflets rolled up into bead-like bodies.

 Roots: creeping rhizomes up to 0.5 inch thick

 Flowers: Very small bumplike sporangia fruiting bodies, often dark rust brown to grey, found on the backs of the fertile fronds. Fertile fronds are often rolled tightly.

 Seeds: Tiny dustlike spores mature July - August.

 Seedling: Germinates during the first or second week of May. First fronds often emerge with leaflets curled like a fiddle head.

ECONOMIC IMPORTANCE

LIFE CYCLE

Reproduction: perennial

 Propagation: creeping rhizomes, spores

 Dispersal: wind dispersal of spores, contamination of vine cuttings to new plantings

DISTRIBUTION

State: Common throughout Wisconsin.

 National: Found in open meadows, woodlands, and swamps east of the Rocky Mountains.

 Origin:

ENVIRONMENTAL FACTORS

Favors meutral to slightly acidic soils. Common in open meadows, woodlands, and swamps, cranberry beds, dikes, roadsides and adjacent areas. Normally begins to invade cranberry bed edges and then spreads inward.

SCOUTING PROCEDURE/ET

While scouting a cranberry bed for disease and insect pests, identify weed populations as they arise. Note the specie(s) of weed present as well as the population level relative to field area. Example: 10% sensitive fern, 20% boneset and joe-pye weed mix.

REFERENCES

Dana, M. 1987. Cranberry Weeds in Wisconsin. Department of Horticulture, University of Wisconsin-Madison. Madison, Wisconsin. p. 24.

 

Gleason, H. A. 1952. Illustrated Flora of the United States and Adjacent Canada. Vol 1. Lancaster Press, Lancaster, Pennsylvania. p. 37.

Kummer, L. D., T. G. Dittl, and T. D. Planer. 1993. Wisconsin Cranberry Weeds. Wisconsin Cranberry Board, Wisconsin Rapids, Wisconsin. p. 16.

 

McGregor, R. L. 1986. Flora of the Great Plains. University Press of Kansas, Lawrence, Kansas. p. 63.

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