American Hazel

Corylus americana is a weedy species, sometimes considered a pest in carefully managed forests. The nuts are smaller but of the same general quality and flavor as commercial filberts ( Corylus maxima Miller and C . colurna Linnaeus).

Native Americans used Corylus americana medicinally for hives, biliousness, diarrhea, cramps, hay fever, childbirth, hemorrhages, prenatal strength, and teething, to induce vomiting, and to heal cuts (D. E. Moerman 1986).

Shrubs , open, upright, rounded, to 3(--5) m. Bark light gray, smooth. Branches ascending; twigs pubescent, covered with bristly glandular hairs. Winter buds containing inflorescences broadly ovoid, 3--4 × 3--4 mm, apex obtuse to rounded. Leaves: petiole pubescent, densely glandular-bristly. Leaf blade broadly ovate, often with straight sides and slight lobes near apex, giving them squarish appearance, 5--16 × 4--12 cm, moderately thin, base narrowly cordate to narrowly rounded, margins sharply serrate or obscurely doubly serrate, apex abruptly to long-acuminate; surfaces abaxially sparsely to moderately pubescent, velutinous to tomentose along major veins and in vein axils. Inflorescences: staminate catkins lateral along branchlets on very short shoots, usually in clusters of 1--2, 4--8 × 0.5--0.8 cm; peduncles mostly 1--5 mm. Nuts in clusters of 2--5, sometimes partially visible; bracts much enlarged, leaflike, distinct nearly to base, slightly longer than to 2 times length of nuts, apex deeply and irregularly laciniate; bract surfaces downy-pubescent, abaxially stipitate-glandular. 2 n = 22, 28.

Man., Ont., Sask.; Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., La., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Vt., Va., W.Va., Wis.

Flowering very early spring.

Moist to dry open woods and thickets, hillsides, roadsides, fencerows, and waste places; 0--750m.

Corylus americana var. altior Farwell; C. americana var. indehiscens E. J. Palmer & Steyermark; C. americana var. missouriensis A. de Candolle

American hazelnut
Americam hazel
American filbert

More info for the term: shrub

American hazelnut is a large, deciduous, rhizomatous shrub from 3 to 10
feet (1-3 m) tall [5,9].  It has a straight trunk with spreading,
ascending branches, and can form dense thickets. The leaves are 3 to 5
inches (8-12 cm) long.  The male catkins are 8 inches (20 cm) long,
straight, slender, and regularly spaced along the upper stem.  The
female flowers are tiny, almost completely enclosed by bracts, and near
the end of the twigs.  The nuts are enclosed in two leafy
bracts [20,28].  The roots are typically in the upper 6 inches (15 cm)
of soil [6].  Some of the smaller roots run vertically toward the
surface and branch profusely into very fine laterals [34].

American hazelnut occurs from Maine west to Saskatchewan, south to eastern
Oklahoma, east to Georgia, and north through New England [5,17,31].

More info for the term: top-kill

Low- to moderate-severity fires top-kill American hazelnut [7].  It
survives fire by sprouting from rhizomes [7,10].

The underground roots and rhizomes can survive low- to moderate-severity
fires when the humus is moist.  They are relatively shallow, however,
and are vulnerable to fire when the humus is dry and combustible [6].

More info for the terms: basal area, cover, density, fire management, fire regime, forb, forest, fuel, herbaceous, litter, low-severity fire, natural, phenology, potential natural vegetation, potential natural vegetation group, prescribed fire, presence, restoration, series, severity, tree, woodland

In areas where fire has been excluded, a heavy density of American hazelnut
has developed, suppressing desirable tree species and contributing to
fuel buildup [10,21].

Repeated summer fires inhibit the ability of American hazelnut to sprout by
exposing and damaging underground stems and roots and exhausting stored
food reserves.  Single fires may eliminate American hazelnut if humus is
sufficiently dry to be completely consumed [6].


FIRE CASE STUDY:
Effects of repeated prescribed fires at Cedar Creek Natural History Area, Minnesota

• FIRE CASE STUDY CITATION
• SPECIES INCLUDED IN THE STUDY
• FIRE CASE STUDY REFERENCE
  
• STUDY LOCATION
• SITE DESCRIPTION
• PREFIRE PLANT COMMUNITY
• SPECIES PHENOLOGY
• FIRE SEASON/SEVERITY CLASSIFICATION
• FIRE DESCRIPTION
• FIRE EFFECTS ON TARGET SPECIES
• FIRE MANAGEMENT IMPLICATIONS

FIRE CASE STUDY CITATION:


Fryer, Janet L., compiler. 2007.
Effects of repeated prescribed fires at Cedar Creek Natural History Area, Minnesota.
In: Corylus americana.
In: Fire Effects Information System, [Online].
U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station,
Fire Sciences Laboratory (Producer). Available:
https://www.fs.fed.us/database/feis/plants/shrub/corame/all.html#FireCaseStudies [
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SPECIES INCLUDED IN THE STUDY:


This Fire Case Study contains information on the following species:

Common name Scientific name
American hazelnut Corylus americana



FIRE CASE STUDY REFERENCE:


Unless otherwise indicated, the information in this Fire Case Study comes from the following
paper:

Axelrod, A. N.; Irving, F. D. 1978. Some effects of prescribed fire at Cedar
Creek Natural History Area. Journal of the Minnesota Academy of Science. 44(2):
9-11. [3].



STUDY LOCATION:


Prescribed burning was conducted on the Cedar Creek Natural History Area in Anoka and Isanti counties, Minnesota.



SITE DESCRIPTION:


The study sites are on Anoka sand plain upland soils, with fine sands in the
Sartell and Zimmerman series. Topography is generally level [3].



PREFIRE PLANT COMMUNITY:


Cedar Creek Natural History Area contains bur oak-northern pin oak-quaking aspen (Quercus macrocarpa-Q.
ellipsoidalis-Populus tremuloides) woodlands [35],
marshlands, and old fields. The study sites were on the oak woodlands.
American hazelnut clones dominated the understory, and there was an herbaceous ground layer.
Based on the unburned control plots, prefire American hazelnut density was approximately
11 stems/milacre [3].

Study sites are classified in
the following plant community and likely experienced the historic fire regime
described below:


Fire regime information on the vegetation community in which American
hazelnut occurs in this study. Fire regime characteristics are taken from the
LANDFIRE Rapid Assessment Vegetation Model
[38]. This vegetation model was developed
by local experts using available literature, local data,
and expert opinion as documented in the .pdf file linked from the
Potential Natural Vegetation Group listed below.Vegetation Community (Potential Natural Vegetation Group)
Fire severity*
Fire regime
characteristics
Percent of fires
Mean interval
(years)
Minimum interval
(years)
Maximum interval
(years)
Northern oak savanna Replacement 4% 110 50 500
Mixed 9% 50 15 150
Surface or low 87% 5 1 20

*Fire Severities:
Replacement=Any fire that causes greater than 75% top removal of a vegetation-fuel type,
resulting in general replacement of existing vegetation; may or may not cause a lethal effect on the plants.

Surface or low=Any fire that causes less than 25% upper layer replacement and/or
removal in a vegetation-fuel class but burns 5% or more of the area.

Mixed=Any fire burning more than 5% of an area that does not qualify as a replacement, surface, or low-severity fire;
includes mosaic and other fires that are intermediate in effects
[36,37].




SPECIES PHENOLOGY:


American hazelnut phenology was not described. American hazelnut was probably
rapidly elongating its stems
during the spring fires and flowering during the summer fires.



FIRE SEASON/SEVERITY CLASSIFICATION:


Spring/low and moderate severity

Summer/moderate severity



FIRE DESCRIPTION:


Fire Management Objective:
Various repeat prescribed fire treatments were conducted to open stand structure in Cedar Creek's
oak woodland. Prescribed burning was conducted over
an 8-year period. The specific management objective was to reduce American hazelnut presence
in the understory.

Fire prescription and behavior:
Four fire treatment sites and an unburned control were selected for this study.
Prescribed burning was conducted annually or on fire-and-rest cycles. A total of
19 prescribed fires were conducted on the 4 burn units. Seventeen of the fires
were conducted in spring, with the earliest fire on 11 April 1969 and the latest
on 16 May 1972. Surface fuels were oak litter and grasses (Poaceae). Fires on
spring-burned sites were conducted before green-up, when surface fuels were mostly or completely
cured. The majority of the prescribed fires were of moderate severity and fairly continuous; however,
Site 3 experienced 2 low-severity, patchy summer fires before the moderate-severity
April 1969 fire gave satisfactory fire continuity. April and May fires were ignited
in the late afternoon, usually after 5:00 p.m., 3 to 10 days after measurable precipitation. 
Strip head fires were used.

Stocking and treatment dates of prescribed-burn
sites on Cedar Creek, MN
Site Treatment Area (acres) 1972 basal area (ft?) Rx fire dates
Site 1 7 burns in 8 years 27 70 4 May 1965,
25 April 1966,
11 April 1967,
26 April 1968,

12 May 1969,
12 April 1971,
16 May 1972
Site 2 8 burns in 8 years 25 42 4 May 1965,
13 April 1966,
5 May 1967,
26 April 1968,

12 May 1969,
4 May 1970,
3 May 1971,
25 April 1972
Site 3 3 burns in 7 years 10 64 30 August 1966,
6 September 1967,
23 April 1969
Site 4 1 burn in 5 years 27 61 14 May 1969
Site 5 unburned control not provided 60 no recent fires

Weather conditions on days of burning ranged as follows:

Weather conditions and fire behavior for the
Cedar Creek burns
Air temperature Relative humidity Windspeed Rate of spread Fuel consumption Flame height* Depth of flame front*
56-91 ?F 26%-72% 1-20 mph 8-15 ft/min 917-6,500 lbs/acre ~2 in-3 ft <1ft in grass fuels

~3 feet in thick oak litter

*Flame height and flame front measures are for
spring fires only. These measures were not provided for the summer fire on
Site 3.

Green-up had begun on some sites burned in late spring,, so herbaceous surface fuels were only
partially cured. These late spring fires burned at lower severities, had slower
rates of spread, and produced more smoke than the other spring fires.


FIRE EFFECTS ON TARGET SPECIES:


All the spring fires top-killed American hazelnut clones. Duration of flame
contact with American hazelnut stems was usually less than 1 minute, which was
enough to kill the cambium of aboveground stems. American hazelnut stems on
sites with heavy concentrations of fallen branches and other downed woody debris
from wind-damaged oaks remained in direct contact with flames for as long as 10
minutes. Effects of this longer-burning woody debris on American hazelnut's
underground system were not noted. Effects of the fires on stand structure
and American hazelnut growth are shown below.

Overstory density and American hazelnut density,

height, and biomass on study plots in the 4th
postfire growing season. Data are means (SD).
Treatment Oak overstory basal area (ft/acre) American hazelnut basal area (stems/0.001 acre) Stem height* (inches) Stem biomass (g)
Site 1 (7 burns in 8 years) 70 (46) 19.2 (4.6) 16 (6.1) 16.3 (3.6)
Site 2 (8 burns in 8 years) 42 (68) 19.9 (8.4) 18 (6.1) 30.6 (16.4)
Site 3 (3 burns in 7 years) 64 (39) 8.0 (2.7) 34 (14) 117 (92.2)
Site 4 (1 burn in 5 years) 61 (51) 10.0 (6.2) 30 (9.4) 92.1 (49.4)
Site 5 (unburned control) 60 (44) 11.0 (4.6) 33 (14.2) 150.4 (85.3)
*For American hazelnut stem
height, data are the means of the longest stem on each of 218 plots.

Statistical analyses showed no significant differences (P=0.05 for all
study measures) between either American hazelnut density or stem height on Sites 1 and 2, the annual
burn treatments. Similarly, there were no significant differences in stem
density or stem height between Sites 3 and 4, the treatments with rest years between fire
treatments. Data for the 2 annual fire treatments were therefore pooled and
compared to pooled data for the 2 fire-and-rest treatments. American
hazelnut stocking was significantly denser on annually burned plots (Sites 1 and
2) compared to fire-and-rest plots (Sites 3 and 4), and American hazelnut stems
were significantly taller on fire-and-rest plots (Sites
3 and 4) compared to annually burned plots. The authors attribute
these differences to age variation in American hazelnut stems. Annually burned plots had
only even-aged, 1-year-old stems. As time since fire increased on fire-and-rest plots,
even-aged stems from the first postfire growing season were
augmented with younger, shorter stems.

Both annual fire and fire-and-rest treatments initially reduced American
hazelnut stem density and height compared to the control; however, by fourth
growing season following 1 to 3 fires, there were no significant differences
between American hazelnut density, stem height, or biomass on fire-and-rest
plots compared to unburned plots. However, the series of annual fires
approximately doubled American hazelnut density and reduced mean stem height to
about one-half that of American hazelnut stems on unburned plots. Stems on
unburned plots were older and larger than stems on burned plots, so biomass of
unburned stems was approximately
4 times more than biomass of stems on annually burned plots.



FIRE MANAGEMENT IMPLICATIONS:


Fire management objective: The
series of annual fires successfully controlled American hazelnut.
Although density increased, the proportion of the understory occupied by
American hazelnut was less due to reductions in height and biomass. Fire-and-rest
treatments did not control
American hazelnut.

Statistical analyses of the effects of the various fire treatments on the oak
overstory were not provided. Based on overstory oak basal area, overstory stand structures
were similar on fire-and-rest plots and control plots. The Site 1 annual burn
plots had greater oak density than the fire-and-rest and control plots, while
overstory density on the Site 2 annual burn plots was less than fire-and-rest
and control plots. Further burning treatments on Cedar Creek and restoration
fires on similar oak woodland/American hazelnut sites may help explain discrepancies in these study results.

Fire control of American hazelnut:
The authors recommend repeated burning on a
regular schedule to restore and maintain oak savannas. Field observations by the
authors suggested that grass and forb cover increased where American
hazelnut height and biomass were reduced by annual burning.

The effect of repeated fires on American hazelnut was temporary, however. In this study,
American hazelnut regained most of its prefire
biomass by the fourth postfire growing season on fire-and-rest sites. Axelrod and Irving [3]
predict that if burning is conducted at less than 7-year intervals, American hazelnut will completely
regain its prefire height and biomass. The results of this study suggest that a
schedule of annual or nearly annual fires provides optimal American hazelnut control.

More info on this topic.

More info for the term: phanerophyte

Phanerophyte

More info for the term: forest

American hazelnut occurs along streams, hedgerows, meadows, woodlands,
roadsides, and forest margins.  It grows best on rich, moist,
well-drained soils [20,31,34]

Common understory associates of American hazelnut include shagbark hickory
(Carya ovata), raspberry (Rubus spp.), smooth sumac (Rhus glabra),
chokecherry (Prunus virginiana), arrowwood (Viburnum rafinesquianum),
eastern hophornbeam (Ostrya virginiana), and dogwood (Cornus spp.)
[1,2,10].

More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

     1  Jack pine
     5  Balsam fir
    12  Black spruce
    13  Black spruce - tamarack
    14  Northern pin oak
    15  Red pine
    16  Aspen
    17  Pin cherry
    18  Paper birch
    20  White pine - northern red oak - red maple
    21  Eastern white pine
    22  White pine - hemlock
    23  Eastern hemlock
    24  Hemlock - yellow birch
    25  Sugar maple - beech - yellow birch
    26  Sugar maple - basswood
    27  Sugar maple
    30  Red spruce - yellow birch
    31  Red spruce - sugar maple - beech
    32  Red spruce
    35  Paper birch - red spruce - balsam fir
    39  Black ash - American elm - red maple
    40  Post oak - blackjack oak
    42  Bur oak
    43  Bear oak
    44  Chestnut oak
    51  White pine - chestnut oak
    52  White oak - black oak - northern red oak
    53  White oak
    55  Northern red oak
    57  Yellow-poplar
    58  Yellow-poplar - eastern hemlock
    59  Yellow-poplar - white oak - northern red oak
    60  Beech - sugar maple
    62  Silver maple - American elm
    76  Shortleaf pine - oak
    78  Virginia pine - oak
   108  Red maple
   110  Black oak

More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

   FRES10  White - red - jack pine
   FRES11  Spruce - fir
   FRES14  Oak - pine
   FRES15  Oak - hickory
   FRES17  Elm - ash - cottonwood
   FRES18  Maple - beech - birch
   FRES19  Aspen - birch

More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

More info for the term: forest

   K081  Oak savanna
   K093  Great Lakes spruce - fir forest
   K095  Great Lakes pine forest
   K099  Maple - basswood forest
   K100  Oak - hickory forest
   K101  Elm - ash forest
   K103  Mixed mesophytic forest
   K104  Appalachian oak forest
   K106  Northern hardwoods
   K108  Northern hardwoods - spruce forest
   K100  Oak - hickory forest
   K111  Oak - hickory - pine forest
   K112  Southern mixed forest

The leaves, twigs, and catkins of American hazelnut are browsed by deer and
moose [11,24].  The nuts are eaten by small mammals, northern bobwhite,
ruffed grouse and other large birds, and deer [19.20].  Beaver eat the bark
[20].

More info for the terms: codominant, forest, shrub

American hazelnut is a dominant or codominant shrub in maple-basswood
(Acer-Tilia) forests of Wisconsin and Minnesota [12].  In Nebraska,
American hazelnut is a dominant shrub in the ecotone of forest and prairie
[1,33].  It is a dominant understory species in jack pine (Pinus
banksiana), paper birch (Betula papyrifera), trembling aspen (Populus
tremuloides), and northern pin oak (Quercus ellipsoidalis) communities of
northern Wisconsin [4].

More info for the term: shrub

Shrub

American hazelnut often competes with hardwoods and pines for light and
moisture [25,27].  Because of shading and
aggressive growth, it has long
been recognized as a major deterrent to the successful regeneration of
upland conifers [6]. American and beaked
hazelnut (C. cornuta) are
responsible for much of the failure of red pine (Pinus resinosa)
regeneration in Minnesota [13].

American hazelnut can be controlled with herbicides [22,25].

American hazelnut has a fairly high protein and energy value.  Percentage
composition (dry weight) of the nuts is as follows [32]:

     crude protein       25.81
     crude fiber          2.10
     available protein   23.25
     calcium              0.28
     phosphorus           0.39

     AL  AR  GA  IL  IN  IA  KS  KY  LA  ME
     MD  MA  MI  MN  MS  MO  NH  NJ  NY  NC
     ND  OH  OK  PA  RI  SC  SD  TN  VT  VA
     WV  WI  MB  ON  PQ  SK

American hazelnut has been cultivated as an ornamental since 1798.  It is
also commercially cultivated for nut production.  The sweet nuts may be
eaten raw or ground and made into a cakelike bread [31].  The nuts were
used by Native Americans to flavor soups [16].

More info on this topic.

The flowers of American hazelnut are formed in the summer and open the
following spring, before the leaves emerge.  By late summer or early
fall, the fertilized flowers develop into fruits [5].

More info for the terms: fire regime, rhizome, secondary colonizer, seed, shrub

   Rhizomatous shrub, rhizome in soil
   Secondary colonizer - off-site seed

FIRE REGIMES :
Find fire regime information for the plant communities in
which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".

More info for the term: seed

American hazelnut reproduces both sexually and asexually.  It begins
producing seed after the first year, and produces good seed crops
every 2 to 3 years.  Seed dispersal is chiefly by mammals or birds [5].

Vegetative Reproduction:  The most important mode of reproduction of
American hazelnut is from rhizomes [6].  The large, woody rhizomes are 4 to
6 inches (10-15 cm) below the surface.  Rhizomes give rise to new shoots
1 to 2 feet (30-60 cm) from the parent plant [34].

More info on this topic.

This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

   14  Great Plains

More info on this topic.

More info for the term: forest

American hazelnut is shade tolerant [33].  It can grow under a light
intensity of 15 percent or less; even as low as 1 percent [1].  It is a
mid-seral species, and is usually absent in old-growth forest
communities [2].

More info for the term: fern

The currently accepted scientific name for American hazelnut is Corylus
americana Walt. [17,31]. Two subspecific taxa based on morphological
differences are found in southwestern Missouri and southeastern Kansas:
C. a. var. indehiscens Palm. & Steyerm. and C. a. forma missouriensis
(A. DC.) Fern. [18].

Corylus americana, the American hazelnut or American hazel, is a species of deciduous shrub in the genus Corylus, native to the eastern and central United States and extreme southern parts of eastern and central Canada.