Summary of 2012 Fire Effects Monitoring for the Southern Blue Ridge Fire Learning Network 1. Peter Bates 2 December 21, 2012

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1 Summary of 212 Fire Effects Monitoring for the Southern Blue Ridge Fire Learning Network 1 Peter Bates 2 December 21, 212 Introduction: Forest Stewards, Inc. entered into a contract with The Nature Conservancy to monitor fire effects on prescribed burn demonstration sites for the Southern Blue Ridge Fire Learning Network (SBR FLN). We completed the following tasks as part of that contract: 1. During the summer of 212 we collected post-burn data for 4 sites (Flat Branch, Lake James, Needmore, and Steeltrap Knob). 2. Began initial data summarization and presented the results in a poster and the 212 National Convention of the Society of American Foresters Convention in Spokane, WA. 3. Presented a webinar on November 29, 212 describing an ecozone approach to summarizing results. That presentation serves as an outline for a proposed journal article. Field Data Collection Methods: All data were collected using 1/1 acre permanent plots. During this data collection effort, 3 plots were measured within the burn unit for Cold Mountain #1, 1 plots were measured within the burn unit for Cold Mountain #2, 18 plots were measured in the area around the Cold Mountain sites, and these will serve as control plots for both Cold Mountain #1 and #2. An additional 2 plots were established at Woods Gap. Fifteen were located within the proposed burn unit and 5 were located in a control area. The data collected at each plot are described below: Data Type Plot location Aspect Landform Elevation Slope Slope position Slope shape Photos Fuels Trees (data collected for all trees > 2 inches DBH within a 1/1 th acre fixed radius plot) Methods and Attributes UTM coordinates of plot center collected by averaging at least 2 GPS positions Azimuth with a compass NCVS categories: ridgetop, open slope, spur ridge, gap, knob, plunging cove, valley bottom, bench Determined from DEM/GIS based on UTM coordinates Nearest percent with a clinometer Classified as either upper, mid, lower Classified as either flat, concave, convex 1 repeatable photo point established per plot Litter and duff depths Count of 1-hr, 1-hr, 1-hr, and 1-hr fuels (woody 3 diameter at intersection) by diameter Data collected and summarized using protocols developed by Southern Research Station, Clemson office. Species DBH Crown class: Dominant, Codominant, Intermediate, or Overtopped Mortality class based on percent live crown 1 Final report prepared by Forest Stewards, Inc and presented to The Nature Conservancy in reference to contract number FIRE_FSI_ Department of Geosciences and Natural Resources, Western Carolina University (bates@ .wcu.edu)

2 Regeneration (data will be collected for all tree species > 1 ft tall and < 2 inches DBH within a 1/5 th acre fixed radius plot) Understory (data will be collected for non-tree species in the same 1/5 th acre plot as Advanced Regeneration data) Stem count by species Stem height: 1 to 2.99 ft 3 to 4.49 ft > 4.5 ft Stem origin: Sprout/sucker Single stem Sprout clumps will be treated as a single plant with height of tallest stem measured % Cover in 5% increments plus -1, 1-2, 2-3, 3-4, 4-5% for the following life forms: bare ground boulder moss/lichen grass/grass-like ferns other herbs/forbs vines deciduous shrubs evergreen shrubs (includes mountain laurel and rhododendron) mountain laurel rhododendron Overview of SBR FLN demonstration burn units: When combining the this year s efforts with those of the past, Forest Stewards, Inc, and WCU have been involved in data collection and monitoring on a total of 13 SBR FLN burn units (Fig. 1). At least 1 controlled burn has been completed on 1 of the 13 burn units, and the remaining 3 are prepped and scheduled to be burned as soon as conditions allow. Other characteristics of the burn units include (Table 1): 8 of the units target Oak community types and 5 units target Yellow Pine community types 9 units have been burned once, 1 has been burned twice, and 3 have yet to be burned 7 of the units burned to date have been spring burns and 3 of the units burned to date have been fall burns.

3 Figure 1. Locations of SBR FLN burn units being monitored by Forest Stewards, Inc and Western Carolina University as of December, 212.

4 Table 1. Overview of SBR FLN demonstration burn units. Cells in green represent periods of data collection. HERB indicates a satellite study where non-mast species < 6 inches DBH were treated with herbicide. Cells in red represent years of prescribed burns. All burns are spring burns unless another season is indicated. Completed Not completed unit Target community(ies) Flat Branch Yellow Creek Needmore Steeltrap Knob Tugalo Village Silver Run Cold Mountain #1 Cold Mountain #2 Davis Creek Lake James Woods Gap Bluff Mountain 3 top Mountain Shortleaf pineoak Shortleaf pineoak Shortleaf pineoak High elevation red oak Shortleaf pineoak Dry mesic oakhickory High elevation red oak High elevation red oak High elevation red oak Shortleaf pineoak Dry mesic oakhickory High elevation red oak High elevation red oak Pine-oak-heath Pine-oak-heath Dry mesic oakhickory Dry mesic oakhickory Dry mesic oakhickory Dry mesic oakhickory HERB FALL FALL FALL The following figures show pre and post burn results for overstory basal by species and advanced regeneration by species for each of the 4 burn units sampled this summer (Flat Branch, Lake James, Needmore, and Steeltrap Knob). In all cases, postburn results represent conditions in the 2 nd growing season after the fire.

5 Density (stems/acre) Basal area (ft^2/acre) 6 5 Overstory basal area for the Flat Branch burn unit preburn and during the second growing season following the burn 4 3 Total preburn BA: ft2/acre Total postburn BA: ft2/acre Advanced regeneration for the Flat Branch burn unit preburn and during the second growing season following the burn 4 3 Total preburn density: 186 stems/acre Total postburn density: 99 stems/acre 2 1

6 Density (stems/acre) Basal Area (ft^2/acre) Overstory basal area for the Lake James burn unit preburn and during the second growing season following the burn Total preburn BA: 92.3 ft2/acre Total postburn BA: 92.1 ft2/acre Advanced regeneration for the Lake James burn unit preburn and during the second growing season following the burn Total preburn density: 547 stems/acre Total postburn density: 413 stems/acre

7 Density (stems/acre) Basal area (ft^2/acre) 6 5 Overstory basal area for the Needmore burn unit preburn and during the second growing season following the burn 4 3 Total preburn BA: ft2/acre Total postburn BA: ft2/acre Advanced regeneration for the Needmore burn unit preburn and during the second growing season following the burn 5 4 Total preburn density: 22 stems/acre Total postburn density: 212 stems/acre 3 2 1

8 Density (stems/acre) Basal area (ft^2/acre) 5 45 Overstory basal area for the Steeltrap Knob burn unit preburn and during the second growing season following the burn Total preburn BA: ft2/acre Total postburn BA: ft2/acre Advanced regeneration for the Steeltrap Knob burn unit preburn and during the second growing season following the burn 2 15 Total preburn density: 1247 stems/acre Total postburn density: 917 stems/acre 1 5

9 Summarizing results by ecological zone: We propose that it may be most appropriate to analyze and present results by ecological zone rather than by individual burn units. There is considerable variability within each burn unit, which makes interpretation of the results difficult. Summarizing the results by ecozone will allow us to work around some of this variability, and perhaps more importantly, would allow us to extrapolate our results to similar ecozones across the landscape. The latter would provide resource managers with a better tool to assess how best to use fire in landscape-scale restoration efforts. For our analyses, we used ecozones developed by Steve Simon, which have been the principal ecological units used by the SBR FLN. Table 2 shows the distribution of those units within our burn units. Table 2. Area (acres) of each Simon Ecozone type in each burn unit Ecozone Dry Mesic Oak Montane Oak Pine- Oak Heath Acidic Rich Shortleaf Total unit Unit Cove HERO Cove Pine Oak area (ac) FlatBranch ,279 YellowCreek Needmore Steeltrap Tugalo Vil ,311 2,426 SilverRun ColdMtn ColdMtn DavisCrk ,45 LakeJames ,954 WoodsGap ,632 Bluff Mtn Top Mtn Total (ac) 1,66 3, , ,515 1,897 Our plots were primarily located in 6 of 7 ecozones that were most common in our burn units. We had very few plots in areas classified as Acidic Coves, which is consistent with the fact that that we did not target coves during plot location. We have pre and postburn data for 15 plots located within the 6 ecozones, and we used those plots to evaluate fire effects by ecozone (Table 3). Table 3. Number of plots in each ecozone Ecozone # Plots Dry Mesic Oak 16 HERO 7 Montane Oak 33 Pine Oak Heath 5 Rich Cove 7 Yellow Pine Oak 31 Grand Total 15

10 Arboreal Moisture Index Ecozone characterzation: We developed an Arborial Moisture Index (AMI) based on the species composition of the overstory trees (modeled after McNab 23). Each tree was assigned a moisture index value ranging from 1 (xeric) to 1 (mesic) based on conditions where that species is typically found in the southern Appalachians. AMI is calculated for each plot based on the average of those values for each overstory tree in the plot. AMI varied significantly with ecozone (F=55, P <.1), and the values followed a logical pattern. This to supports that the ecozones were identifying unique ecological units (Fig. 2). 7 Figure Pine Oak Heath Dry Mesic Oak Yellow Pine Oak Montane Oak Rich Cove HERO

11 BA reduction (%) Fire effects on overstory mortality: For many of our target communities, restoration will require some reduction in the forest overstory. We examined total mortality of stems between 2 and 6 in DBH to evaluate whether changes in stand structure were occurring after 1 burn, and we summarized the results by ecozone. Ecozones varied significantly in both the number of stems per acre killed (F=11, P <.1) and percent of stems remaining (F=52, P <.1) as measured in the second growing season following a single burn (Fig. 3): Number killed Percent remaining Figure Dry Mesic Oak Yellow Pine Oak Rich Cove HERO Montane Oak Pine Oak Heath We also found significant differences by ecozone in the percent in basal area reduction in the intermediate and overtopped crown classes (F=443, P <.1) (Fig. 4). 8 7 Figure HERO Dry Mesic Oak Rich Cove Yellow Pine Oak Montane Oak Pine Oak Heath Fire effects on regeneration: We enter into the following discussion with the caveat that we feel it is premature to begin rigorously assessing fire effects on regeneration. We have only collected postburn fire results for 7 of our 13 burn units. In addition, except for 1 unit, all of our results are for a single burn, the effects of which are often considered uninformative. However, we do present the following observations to demonstrate some initial trends and observations.

12 Density (stems/acre) Regeneration density: For most ecozones, there seemed to be a slight (though likely insignificant) decrease in the density of advanced regeneration in the second growing season following the burn. The one exception was in the Pine Oak Heath ecozone where regeneration density did increase (Fig. 5). In is interesting that this is also the ecozone that experienced the greatest reduction in basal area of trees in intermediate and overtopped crown classes (Fig. 4) suggesting that opening these stands up more might have stimulated a regeneration response Figure Dry Mesic Oak HERO Montane Oak Pine Oak Heath Rich Cove Yellow Pine Oak

13 Density (stems/acre) Density (stems/acre) Regeneration by species groups: In this analysis we looked at whether different groups of species responded differently to fire. Regenerating species were grouped into 3 categories, Oak (all oaks and hickories), Yellow Pine (all yellow pines), and Mesophytic (all other species). We have observed very little Yellow Pine regeneration (either pre or postburn), so we only present the results for Oak and Mesophytic (Fig. 6). Again, while no statistical analyses were done, there is no strong indivation that either species group responded differently than the other in any of the ecozones. In all ecozones (with the exception of Pine Oak Heath), there may have been a slight decrease in regeneration density, but the decrease was similar for both species groups. Similarly, in the Pine Oak Heath ecozone, where there appeared to be an increase in regeneration density following a single burn, both Oak and Mesophytic species responded positively Figure Oak Dry Mesic Oak HERO Montane Oak Pine Oak Heath Rich Cove Yellow Pine Oak Mesphytic Dry Mesic Oak HERO Montane Oak Pine Oak Heath Rich Cove Yellow Pine Oak

14 Density (stems/ac) Regeneration of individual species: We pooled the results for individual species across all ecozones to look for trends (Fig. 7). Again, we urge caution when interpreting these data; however the results do seem to support several observations that were made in the field. First, some species appeared to be stimulated by a single burn in some locations. These included sassafras, blackgum, and black locust, all species that sucker from the roots. Conversely, white pine regeneration appeared to be drastically reduced by a single burn. We should be able to refine these results further as our monitoring continues and we gather results from additional sites. 1 9 Figure

15 Percent of crown with acorns Fire effects on hard mast production (Cold Mt #1): At Cold Mt #1, the NC Wildlife Resources Commission has been collecting hard mast data from about 5 oaks and hickories located inside the burn unit and from another 5 trees outside the burn unit. Mast production was estimated based on the percent of the crown with acorns or nuts as determined in mid to late summer. Data collection began in 26 prior to the initial burn and has continued each summer through 212. This unit has been burned twice once during the spring of 27 and again during the spring of 21. It appeared that prescribed burning generally stimulated hard mast production. The effects appeared greatest in the year of a burn, and then tended to taper off in subsequent years. The pattern was similar after each of the 2 burns. White oaks demonstrated the greatest response, with trees inside the burn unit showing significantly greater acorn production in the summer immediately after a spring burn (Fig. 8, Table 3) GS post 1st Unburned 2GS post 1st ed 3GS post 1st 1GS post 2nd. Figure 8. White Oaks 2GS post 2nd. 3GS post 2nd. Table 4. T-test results comparing unburned versus burned mast production for each year for white oaks Percent crown with acorns Unburned ed Year Period mean var sd mean var sd P-value GS post 1st GS post 1st GS post 1st GS post 2nd GS post 2nd NA 212 3GS post 2nd

16 Percent of crown with acorns Similar patterns were also observed for Hickories (Fig. 9, Table 5) and Red Oaks (Fig. 1, Table 6) Unburned ed Figure 9. Hickories GS post 1st 2GS post 1st 3GS post 1st 1GS post 2nd. 2GS post 2nd. 3GS post 2nd. Table 5. T-test results comparing unburned versus burned mast production for each year for hickories Percent crown with acorns Unburned ed Year Period mean var sd mean var sd P-value GS post 1st GS post 1st GS post 1st GS post 2nd GS post 2nd GS post 2nd

17 Percent of crown with acorns Unburned ed Figure 1. Red Oaks GS post 1st 2GS post 1st 3GS post 1st 1GS post 2nd. 2GS post 2nd. 3GS post 2nd. Table 6. T-test results comparing unburned versus burned mast production for each year for red oaks Percent crown with acorns Unburned ed Year Period mean var sd mean var sd P-value GS post 1st GS post 1st GS post 1st GS post 2nd GS post 2nd GS post 2nd