Regeneration and Understory ConditionsWilliam H. McWilliams, Randall S. Morin, Tonya W. Lister, and James A. WestfallUSDA Forest Service, Northeastern Research Station, Forest Inventory and Analysis

Methods

Results of Regeneration Study

Result of Exotics Study

Review Basic Hypotheses

Hypothesis1: advance regeneration is bleak

Hypothesis2: understory vegetation is extensive?

Hypothesis3: native invasive species are everywhere

Hypothesis4: non-native invasive species are everywhere and expanding

Hypotheses

Jim Finley, Peter Gould, Kim Steiner

Dan Devlin, Matt Keefer, Stephen L. Sterner

Robert White, Lois DeMarco

NE RWU 4152: Pat Brose, Steve Horsley, Susan Stout

NE RWU 4557: Kurt Gottschalk, Gary Miller

NE RWU 4801: William H. McWilliams, Tonya W. Lister, and James A. Westfall

Regeneration Study

1 2 3 4 5 11 2 3 4 5 1

4 5 1 2 33

4 5 1 2 33

Year One

Year Three

Year Four

Year Five

Five-Year Panel

Year Two

Study Design: Regeneration Study Samples

Interpenetrating Sub-Panel of FIA Sample Locations

Regeneration Sample

Sampling Protocols: Three Levels

Condition B = Nonforest Land Use

Condition A =Forest Land Use

Old 1/5-acre plot Sample Location Level

Deer Impact: Record on of five Deer Impact classes: (after Marquis et al. 1994)Very LowLowMediumHighVery High

Subplot Level

Condition Class

Site Limitations

Associated Understory Vegetation: Assign Percent cover classes to Species/Life Form.

Species/Life Form Shrubs (detailed code) Vines (detailed code) Fern (Bracken, Hay-Scented, and New York) Other fern Grass Other herbaceous

Percent Cover Class (after Marquis et al 1994)

Microplot Level

Condition class

Site limitations

Dominant Tree: If present, record the species of the most dominant tree at least 5.0 inches in diameter.

Seedling Tally: Count all established seedlings at least 2” tall by:

Species

Seedling Source (stump sprout and other) Stump Sprout Other Seedling Competitive oak, hickory, walnut, or butternut seedling

Height Class 2 inches to 6 inches 3 feet to 5 feet 6 inches to 1 foot 5 feet to 10 feet 1 foot to 3 feet Greater than 10 feet

Numbers of seedlings

The Subplot is also where Exotic Invasives

Are Tallied

Degree of Establishment

Tally Requirements:

All seedlings (trees less than 1.0-inches DBH) rooted within the microplot, and

At least 2-inches tall with at least two normal-sized leaves that do not still bear cotyledons, and

Tug Test – the standard “tug test” is used to determine whether seedlings have been established in the previous year’s growing season. Seedlings that slip out of the ground with a “slight” tug should not be tallied. Examination of roots systems will reveal that seedlings that don’t slip out have more developed root systems than first-year seedlings.

Degree of Establishment for Large-Seeded Species

Based on Root-Collar Diameter (Brose unpublished)

Established = 0.20 in.

Competitive = 0.75 in.

Root Length = 8 ft. (not shown)

Root Length = 3 ft. (not shown)

1-inch

1-inch

Desirable

Black cherryOakSugar mapleRed mapleConiferHickoryYellow-PoplarAshBasswoodCucumbertreeWalnutButternut

Commercial

Black cherryOakSugar mapleRed mapleConiferHickoryYellow-PoplarAshBasswoodCucumbertreeWalnutButternutBirchBeechBlackgumElmBlack locustHackberryAspen

All Woody

Black cherry Honey LocustOak SassafrasSugar maple IronwoodRed maple AilanthiusConifer Mountain ashHickory Blue beechYellow-Poplar HawthornAsh DogwoodBasswood RedbudCucumbertree Pin cherryWalnut Striped mapleButternut Hercules clubBirch Scrub oakBeech ChokecherryBlackgum ShadbushElmBlack locustHackberryAspen

Species Composition Group(Timber Management)

Species Composition Group(Canopy Replacement)

1Dominants: includes species that account for at least 2 percent of total live-tree biomass within the state and typically form high canopy.

Dominant

Black cherryOakSugar mapleRed mapleWhite pineEastern hemlockHickoryYellow-PoplarAshBlack birchBeech

Other Dominants

Black cherryOakSugar mapleRed mapleWhite pineEastern hemlockHickoryYellow-PoplarAshBlack birchBeechOther High Canopy Species

2Other Dominants: All other native species that typically exhibit the ability to form high canopy.

All Woody

Black cherryOakSugar mapleRed mapleWhite pineHickoryEastern hemlockHickoryBasswoodYellow-Poplar AshBlack birchBeechOther High Canopy SpeciesAll Other Woody Species

3All Woody: all other woody tree species, such as striped maple, hawthorn, hornbeam, pin cherry, etc..

Seedling Regeneration Stocking Requirements

Two levels of acceptable seedling density per acre were used to account for the range of regeneration guidelines found in the literature (Leak 1980, Sander and others 1976, Marquis and Bjorkbom 1982). These two levels of regeneration stocking are referred to as “moderate-deer” and “high-deer,” respectively. The moderate-deer level requires at least 25 seedlings per microplot. The high-deer level requires at least 100 seedlings per microplot. The moderate-deer level is representative of guidelines developed for central hardwood stands. The high-deer level is reflective of higher levels required in regions with relatively high levels of deer impact.

Weighted Counts:

2 to 6 inches 16 inches to 1 foot 11 to 3 feet 23 to 5 feet 205 to 10 feet 50Greater than 10 feet 50

Analyzing the Results

Applied the regeneration guidelines and evaluated the results for the two species groupings and deer population levels after screening for samples where the forest floor would receive enough light for seedling development, or from 40 to 75 percent stocking based on relative stocking.

Plateau

Central AppalachiansBroadleaf

Broadleaf

Glacial Limit

Eco-Regions

Use the Game Commission Wildlife Management Units for spatial analysis

Desirable Commercial Woody

34 % 47 % 54 %

Interpretation:

Desirable: about two-thirds would likely fail to regenerate.

Commercial: about half would likely fail.

Woody: about half would likely fail.

Percent of Samples Meeting Regeneration Criteria, Timber Management(Samples from 40% to 75% Stocked – High Deer)

Percent of Samples Meeting Regeneration Criteria, Timber Management(Samples from 40% to 75% Stocked – High Deer)

0 – 33% 34-66% 67+%

Wildlife Management Units

No Data

16%

Dominant Other High Canopy Woody

44 % 48 % 54 %

Interpretation:

Dominant: over half would likely fail to regenerate.

Other High Canopy: about half would likely fail.

Woody: about half would likely fail.

Percent of Samples Meeting Regeneration Criteria, Canopy Replacement(Samples from 40% to 75% Stocked – High Deer)

0 – 33% 34-66% 67+%

Percent of Samples Meeting Regeneration Criteria, Canopy Replacement(Samples from 40% to 75% Stocked – High Deer)

No Data

Wildlife Management Units

26%

Percent of Samples with 30% or More Other Vegetation Cover(Samples from 40% to 75% Stocked – High Deer)

0 - 33% 34- 66% 67+%

No Data

Wildlife Management Units

95%

Percent of Samples with 70% or More Other Vegetation Cover(Samples from 40% to 75% Stocked – High Deer)

0 - 33% 34- 66% 67+%

No Data

Wildlife Management Units

71%

Percent of Samples with 30% or More Rhizomous Fern Cover(Samples from 40% to 75% Stocked – High Deer)

0 - 10% 11- 20% 21+%

No Data

Wildlife Management Units

35%

Exotic Invasive Plants StudyVines (8)

Fiveleaf akebiaPorcelain-berryOriental bittersweetEnglish ivyJapanese honeysuckleMile-a-minute vineKudzuCommon periwinkle

Shrubs (19)

Japanese barberryEuropean barberryRussian oliveAutumn oliveWinged EuonymousBorder privetCommon privetBell’s honeysuckleAmur honeysuckleMorrow’s honeysuckleStandish honeysuckleTartarian honeysuckleCommon buckthornGlossy buckthornMultiflora roseWineberryJapanese spiraeaLinden viburnamGuelder rose

Forbes and Grasses (12)

Garlic mustardSpotted knapweedCanada thistleBull thistleCrown-vetchGiant hogweedPurple loosestrifeJapanese stilt grassReed canary grassCommon reedJapanese knotweedGiant knotweed

Percent of Samples with Species PresentMultiflora Rose

Percent of Samples with Species PresentAilanthus

Percent of Samples with Species PresentEuropean/Japanese Barberry

Percent of Samples with Species PresentHoneysuckles

Percent of Samples with Species PresentJapanese Honeysuckle

Percent of Samples with Species PresentOriental Bittersweet

Percent of Samples with Species PresentAutumn/Russian Olive

Percent of Samples with Species PresentGarlic Mustard

Percent of Samples with Species PresentJapanese Stilt Grass

Percent of Samples with Species PresentReed Canary Grass

Percent of Samples with Species PresentJapanese/Giant Knotweed

Percent of Samples with Species PresentGiant Hogweed

?

The End