Fire and Tree-of- Heaven

Transcription

1 Fire and Tree-of- Heaven Does prescribed fire increase the invasiveness of Ailanthus? Joanne Rebbeck Northern Research Station USDA Forest Service Delaware, OH

2 Prescribed Fire in Ohio Forests Increased use of fire in Ohio s public forests Observing invasion and expansion of Ailanthus Little fire effects data on Ailanthus

3 Fire + Tree-of-Heaven A dangerous combination ODNR 1. Top-kill stems resprouting 2. Increase light levels 3. Expose bare ground - seed germination ODNR Lewis ODNR

4 Fire and Fire Surrogate Study Ohio Fire, thinning, and fire + thinning treatments were installed in mixed oak forests in southern Ohio in , as part of the national Fire and Fire Surrogates Study

5 Ailanthus altissima was established in high densities after fire and thinning treatments Hutchinson, Rebbeck, Long (2005)

6 Roadside Survey Map, age and sex Ailanthus trees Very high density of trees ~33 cm DBH Range yrs 65% >50 yrs Few females 30 cm DBH 33 cm (13 in) DBH 45cm (18 in) DBH Control T+B Burn Thin

7 Prescribing fire in managed oak forest landscapes: interactions with the invasive tree Ailanthus altissima Northern Research Station, USDA Forest Service Todd Hutchinson Daniel Yaussy Louis Iverson Ohio Dept. Natural Resources, Division of Forestry Robert Boyles Chad Sanders Mike Bowden Joint Fire Science Program awarded funding in 2008

8 Tar Hollow State Forest 11/04/ acres Utilize a chronology of 12 prescribed fires from 2001 to 2008 on 2,100 acres within an Ailanthus-infested forest

9 Objectives 1.Determine relationship of Ailanthus distribution and abundance to fire intensity, management history, seed sources, and landscape features 2.Quantify the direct effects of prescribed fire on the demography of Ailanthus populations 3.Science Delivery

10 Seeds Individual female tree can produce 200, ,000 seeds/year Prominent seed masses Seeds persist throughout winter

11 1. Distribution and abundance of Ailanthus a. Digital aerial sketch mapping technology to map adult female trees (seed-producers) b. Ground truthing, monitor populations around females, and herbicide treatments ODNR Helicopter Digital Aerial Sketchmapping System

12 Demographic survey of Ailanthus near female trees in burned and unburned areas Additional sampling scheme surrounding female trees in burned & unburned areas Ailanthus female or clump Sample every 20m for 100 m in each direction 19.9 m radius plot to determine Ailanthus presence or absence

13 c. Establish a 400-m systematic grid of plots Quantify the abundance and demography of Ailanthus Fire intensity Management history Site attributes (slope, aspect, moisture, light)

14 d. Produce a model of key factors related to the presence and abundance of Ailanthus across the landscape. Analyze the survey and plot data to develop a general model of Ailanthus in a heterogeneous landscape managed with fire and timber harvesting

15 Nov. 6, acre aerial burn Installed grid point plots mapped female trees Monitored fire intensity (thermocouple probes & data loggers) Monitor post-burn Ailanthus populations in 2009 Preliminary aerial identification of seed-bearing females was successful

16 Lipscomb Hollow Rx Burn Nov. 6, ºF 307ºF 179ºF 187ºF 669ºF 797ºF 315ºF 266ºF 160ºF 130ºF 66ºF 596ºF 453ºF 588ºF Grid point plot Female Ailanthus

17 2. Document the direct effects of prescribed fire and herbicide on the demography of Ailanthus Test the use of pre-burn herbicide application to mitigate the risk of Ailanthus expansion after fire with a replicated experiment

18 Treatments No Burn + No Herbicide No Burn + Herbicide Burn + No Herbicide Burn + Herbicide 2009 Plots installed Pre-treatment data Hack-n-squirt herbicide: imazapyr & glyphosate 2010 Prescribed burn & postburn data 2011 Post-burn data

19 3. Science Delivery Workshop, training sessions, and tours Technical publication with management recommendations Field test recommendations with Wayne National Forest, ODNR Division of Forestry, and The Nature Conservancy

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21 Ailanthus altissima seedling and saplings were established in high densities after fire and thinning treatments Post-treatment seedling and sapling Ailanthus frequency and density, 2003 (3 years post-treatment) Ailanthus frequency (%) Ailanthus density / 100 m BURN THIN T+B 0 BURN THIN T+B Treatment Treatment Hutchinson, Rebbeck, Long (2005)

22 Control N Pre-treatment distribution of Ailanthus trees # ## # ## # ### # # # # # # # ### # Burn # # # # ## Ailanthus adult tree size class distribution # Thin Thin+Burn Number of trees DBH class (cm)

23 Ailanthus Plot Diagram 1m wide X 20m belt transects Aa seedling tallies 39.9 m radius plot: measure presence of Aa by size class Subplot 19.9 m radius plot: All Aa>10cm & saps >1.4cm measured Plot characteristics 1. Photosynthetically active radiation 2. Past fire intensity (e.g. ht of bark char, etc.) 3. Recent management history 4. Distance/direction from seedproducing trees 5. Slope, aspect, overstory basal area, etc.

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