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Table 5 Non-native abundance model estimates with standard error and P-value for the main effects and interaction (treatment by years since treatment). Different letters depict significant differences in shrub cover at α ≤ 0.05. Numbers depict marginal significant levels 0.05 ≤ α ≥ 0.10. Significance codes: *** <0.001, ** <0.01, * <0.05, . <0.1. Estimates (Est), standard errors (± SE), and P-values (P) are rounded to the nearest one hundredth. P-value of *** implies P-value <0.001. Harmfulness rating is from the California Integrated Pest Management and is based on a combination of ecological impact, invasive potential, and current distribution (Bell et al. 2015). The base harmfulness rating in these models is “None.”

From: Decade-Long Plant Community Responses to Shrubland Fuel Hazard Reduction

     Control Fire-fall Fire-winter Fire-spring Mastication-fall Mastication-spring
     Est ± SE P Est ± SE P Est ± SE P Est ± SE P Est ± SE P Est ± SE P
Main effect Intercept   34.84±5.97 *** 38.81±9.50 *** 18.03±8.69 0.04* 14.12±8.89 0.11 92.94±9.20 *** 47.06±7.79 ***
Yr since treatment   −0.16±5.96 0.98 −1.12±1.53 0.46 0.20±1.59 0.9 0.92±1.95 0.64 −1.33±1.27 0.30 0.48±1.15 0.68
Control              
Fire-fall   3.97±10.55 0.71           
Fire-winter   −16.82±9.8 0.09. −20.79±9.78 0.03*         
Fire-spring   −20.72±9.88 0.04* −24.69±10.10 0.01* −3.91±9.53 0.68       
Mastication-fall   58.09±10.42 *** 54.12±10.06 *** 74.9±9.56 *** 78.81±9.98 ***     
Mastication-spring   12.21±9.22 0.19 8.25±9.32 0.38 29.02±8.75 *** 32.93±9.14 *** −45.88±8.62 ***   
Limited   4.30±3.52 0.22 4.30±3.52 0.22 4.30±3.52 0.22 4.30±3.52 0.22 4.30±3.52 0.22 4.30±3.52 0.22
Moderate   −32.44±10.04 *** −32.81±9.38 *** −17.65±10.16 0.08. −16.42±11.9 0.17 −72.91±6.89 *** −40.97±6.29 ***
High   −18.40±8.23 0.03* −21.00±7.81 0.01** −16.86±8.51 0.05* −15.41±8.19 0.06. −65.92±7.09 *** −39.95±6.83 ***
Survey precipitation   −35.91±14.28 0.01* −29.20±7.66 *** −15.49±11.98 0.20 −19.94±12.33 0.11 -75.36±7.09 *** −46.13±6.61 ***
Treatment × yr since treatment Control AB             
Fire-fall AB −0.96±6.09 0.87           
Fire-winter AB 0.37±6.10 0.95 1.33±1.75 0.45         
Fire-spring AB 1.08±6.22 0.86 2.04±2.11 0.33 0.71±2.14 0.74       
Mastication-fall A1 −1.17±6.02 0.85 −0.21±1.41 0.88 −1.53±1.45 0.29 −2.24±1.87 0.23     
Mastication-spring B1 0.64±6.00 0.91 1.60±1.37 0.24 0.28±1.41 0.84 −0.44±1.84 0.81 1.81±0.95 0.06.   
Treatment × harm fulness rating Limited Control AB             
Fire-fall AB −0.38±13.75 0.98           
Fire-winter A1 14.77±14.20 0.30 15.14±13.82 0.27         
Fire spring A1 16.02±15.41 0.30 16.39±15.12 0.28 1.23±15.62 0.94       
Mastication-fall C −40.47±12.17 *** −40.10±11.64 *** −55.26±12.28 *** −56.49±13.75 ***     
Mastication-spring B1 −8.54±11.84 0.47 −8.16±11.29 0.47 −23.32±11.95 0.05. −24.55±13.46 0.07. 31.94±9.33 ***   
Moderate Control AB             
Fire-fall A1 −2.60±11.33 0.82           
Fire-winter A 1.54±11.84 0.90 4.14±11.54 0.72         
Fire-spring A 2.99±11.57 0.80 5.59±11.31 0.62 1.44±11.81 0.90       
Mastication-fall C −47.52±10.84 *** −44.92±10.55 *** −49.06±11.08 *** −50.51±10.82 ***     
Mastication-spring B1 −21.54±10.66 0.04* −18.95±10.37 0.07. −23.08±10.91 0.03* −24.54±10.67 0.02* 25.97±9.84 0.01*   
High Control AB             
Fire-fall A1 6.72±16.17 0.68           
Fire-winter A 20.41±18.66 0.27 13.70±14.21 0.34         
Fire-spring A1 15.97±18.52 0.39 9.26±14.44 0.52 −4.47±17.16 0.79       
Mastication-fall C −39.45±15.93 0.01* −46.16±10.44 *** −59.88±13.92 *** −55.42±14.21 ***     
Mastication-spring B1 −10.22±15.7 0.51 −16.94±10.11 0.09. −30.64±13.67 0.02* −26.19±13.96 0.06. 29.23±9.69 ***