SUPPLEMENTAL TABLES

Table S1. Effect of all treatments on final gravimetric soil moisture. F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Factor F, p

Precipitation 7.981,27, 0.008

Microbial treatment 0.542,27, 0.591

Life-stage 3.511,27, 0.072

Precip.* Soil.Treat. 0.292,27, 0.753

Precip.* Life-stage 0.011,27, 0.919

Mic.Treat.*Life-stage 0.172,27, 0.844

Precip.*Mic.Treat.*Life-stage 0.052,27, 0.954

Table S2. Full-model ANOVA results for the effect of precipitation and all microbial treatments (bulk, autoclaved, and rhizosphere) on germinant responses. Chi- square, F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Germination rate Germinant Germinant total Germinant final Germinant final Days to first (Number of survival biomass (g) Germinant bacterial Germinant final Factor bacterial Inverse germination seeds that (given (given root:shoot community bacterial richness Simpson germinated/ germination) germination) composition pot) F, p χ2, p χ2, p F, p F, p R2 p F, p F, p Precipitation 3.541,50, 0.066 4.30, 0.038 0.06, 0.803 0.841,39, 0.365 8.341,37, 0.006 0.06 <0.001 1.591,14, 0.228 0.031,17, 0.864 Microbial treatment 4.632,51, 0.014 4.79, 0.091 7.06, 0.029 3.982,39, 0.027 0.942,38, 0.398 0.44 <0.001 355.682,15, <0.001 16.472,17, <0.001 Precip.* Microbial 0.682,51, 0.513 1.89, 0.388 2.36, 0.307 10.012,39, <0.001 2.592, 38, 0.088 0.05 0.006 0.702,15, 0.514 0.242,17, 0.789 treatment

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Table S3. Full-model ANOVA results for the effect of precipitation and all microbial treatments (bulk, autoclaved, and rhizosphere) on seedling responses. Chi- square, F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Seedling final Seedling final Seedling specific Seedling Seedling final Seedling total Seedling Seedling bacterial bacterial Factor root length rhizosheath bacterial biomass (g) root:shoot survival community Inverse (cm g dry root-1) weight (g) richness composition Simpson F, p F, p χ2, p F, p F, p R2 p F, p F, p Precipitation 13.421,80, <0.001 1.441,74, 0.234 NA 5.571,18, 0.030 0.101,21, 0.753 0.06 0.011 5.001,18, 0.038 1.401,18, 0.253

Microbial treatment 4.892,80, 0.010 0.312,74, 0.738 15916,<0.001 0.772,17, 0.478 2.592,21, 0.098 0.59 0.004 67.982,18, <0.001 3.902,18, 0.039

Precip.* Microbial 3.342,80, 0.041 0.492,74, 0.617 NA 4.072, 17, 0.036 0.092,21, 0.912 0.07 0.060 2.342,18, 0.124 2.862,18, 0.084 treatment

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Table S4. Full model results for all response variables measured on both life-stages; split by microbial presence (bulk vs. autoclaved) and inocula association history (rhizosphere vs. bulk). Chi-square, F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Survival just Final Bacterial Final Bacterial Bacterial Community Biomass Root:shoot in drought Richness Inv. Simpson Composition Factor χ2, p F, p F, p F, p F, p R2 P Precipitation NA 0.351,76 0.,557 6.441,113, <0.001 3.471,20, 0.077 0.101,23, 0.759 0.06 <0.001 Microbial Presence 5.06, 0.024 7.801,76, 0.007 0.462,113, 0.083 685.071,20, <0.001 12.631,23, 0.002 0.48 <0.001 Life-stage 0.68, 0.408 1.66 , 0.202 23.46 , <0.001 13.85 , 0.001 9.52 , 0.005 0.04 0.006 Microbial 1,78 1,113 1,20 1,23 Precip.* Mic.Pres. NA 1.011,78, 0.302 0.632,113, 0.014 1.301,20, 0.268 0.101,23, 0.757 0.03 0.021 Presence Precip.* Life-stage NA 10.191,76, 0.002 2.251,113, 0.007 0.111,20, 0.741 0.201,23, 0.656 0.02 0.148 Mic.Pres.*Life-stage 1.48, 0.223 0.131,76, 0.721 0.472,113, 0.043 0.011,20, 0.938 1.841,23, 0.189 0.05 0.004 Precip.* Mic.Pres.*Life-stage NA 12.811,78, 0.001 2.362,113, <0.001 0.011,20, 0.939 1.491,23, 0.234 0.02 0.174

Precipitation NA 7.191,87, 0.009 2.741,84, 0.102 3.331,24, 0.080 0.931,24, 0.345 0.021 0.001 Microbial Inocula 0.47, 0.494 0.011,85, 0.921 0.821,84, 0.368 4.061,24, 0.055 6.411,24, 0.018 0.08 0.021 Microbial Life-stage 0.34, 0.558 3.831,4, 0.116 16.491,84, <0.001 1.761,24, 0.197 0.301,24, 0.592 0.02 0.503 Association Precip.* Mic.Inoc. NA 0.271,84, 0.606 0.081,84, 0.777 1.191,24, 0.286 2.101,24, 0.160 0.03 0.245 History Precip.* Life-stage NA 0.251,87, 0.620 0.311,84, 0.578 2.451,24, 0.131 0.451,24, 0.510 0.02 0.343 Mic.Inoc.*Life-stage 0.09, 0.759 0.871,85, 0.354 0.031,84, 0.870 5.541,24, 0.027 3.011,24, 0.092 0.11 0.006

Precip.* Mic.Inoc.*Life-stage NA 0.001,84, 0.996 0.381,84, 0.540 1.631,24, 0.213 2.541,24, 0.124 0.05 0.062

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Table S5. Final bacterial community analyses for microbial presence treatments (autoclaved and bulk microbial treatments only). F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Bacterial

Bacterial Inverse community composition Factor Bacterial richness Simpson (Weighted Unifrac)

F, p F, p R2 p

Precipitation 0.271,8, 0.617 0.011,11, 0.934 0.11 0.007 Germinant Microbial presence 175.641,8, <0.001 1.731,11, 0.216 0.40 0.007

Precip.* Mic.Presence 0.0021,8, 0.970 0.291,11, 0.598 0.05 0.020

Precipitation 0.681,9, 0.432 2.281,9, 0.165 0.06 0.013

Seedling Microbial Presence 210.611,9, <0.001 25.111,9, <0.001 0.62 0.027

Precip.* Mic.Presence 0.071,9, 0.799 3.181,9, 0.108 0.06 0.023

Table S6. Soil properties for initial inocula (autoclaved bulk, live bulk, live rhizosphere) and final seedling-associated soils. Microbial biomass carbon and dissolved organic carbon were only assessed on the seedling ambient-exposed soils (n = 5 per microbial treatment). F-statistic and p-values provided; significant p-values (p < 0.05) are bolded. Final soil Final soil dissolved Final microbial Factor Initial nitrate Initial ammonium Final soil nitrate ammonium organic carbon biomass carbon F, p F, p F, p F, p F, p F, p

Precipitation NA NA 15.221,17, 0.001 5.361,20, 0.031 NA NA Microbial treatment 0.792,11, 0.477 62.792,11, <0.001 9.122,17, 0.002 16.552,20, <0.001 2.6072,10, 0.123 0.912,10, 0.434 Precip.* Microbial NA NA 4.632,17, 0.025 3.432,20, 0.052 NA NA treatment

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Table S7. SIMPER results for bacterial OTUS that differ between the seedling-associated live microbial inocula (rhizosphere and bulk) in drought versus ambient conditions with Weighted Unifrac distance metric. OTUs with significantly greater average percent relative abundance in the drought than ambient soils are presented (p < 0.05). Percent dissimilarity explained refers to the amount of community dissimilarity between the ambient- and drought-exposed bacterial communities that a particular OTU explains. Rows organized by and unadjusted p-value presented.

Percent Avg. % Avg. % dissimilarity rel.abund. rel.abund. Unadjusted OTU explained under drought under ambient Phylum Class Order Family Genus P-value

OTU6729 3.75E-05 0.75 0 Acidobacteria Subgroup_4 UNKONWN Blastocatella 0.023

OTU1520 0.000125 2.5 0 Acidimicrobiia Acidimicrobiales UNKNOWN UNKNOWN 0.025

OTU851 0.000356 9.5 3.125 Actinobacteria Acidimicrobiia Acidimicrobiales UNKNOWN UNKNOWN 0.012

OTU13605 0.000109 2.375 0.25 Actinobacteria Actinobacteria Corynebacteriales Mycobacteriaceae UNKNOWN 0.01

OTU1903 0.000303 7.5 2.25 Actinobacteria Actinobacteria Corynebacteriales Nocardiaceae Smaragdicoccus 0.023

OTU494 0.000109 2.375 0.375 Actinobacteria Actinobacteria Frankiales Acidothermaceae Acidothermus 0.012

OTU272 0.000264 6.75 2.125 Actinobacteria Actinobacteria Frankiales Frankiaceae UNKNOWN 0.018

OTU6546 0.000481 10.875 1.25 Actinobacteria Actinobacteria Frankiales UNKNOWN UNKNOWN 0.002

OTU3122 0.000548 15.375 5.25 Actinobacteria Actinobacteria Frankiales UNKNOWN UNKNOWN 0.013

OTU13146 0.000306 9.75 4.25 Actinobacteria Actinobacteria Kineosporiales Kineosporiaceae UNKNOWN 0.018

OTU768 0.000433 11.625 3.625 Actinobacteria Actinobacteria Propionibacteriales Nocardioidaceae Aeromicrobium 0.007

OTU80 0.000853 36.375 23.375 Actinobacteria Actinobacteria Pseudonocardiales Pseudonocardiaceae Pseudonocardia 0.048

OTU810 0.00035 10.125 3.625 Actinobacteria Actinobacteria Streptomycetales Streptomycetaceae Streptomyces 0.009

OTU478 0.000356 10 4.375 Actinobacteria Gaiellales Gaiellaceae Gaiella 0.035

OTU6042 9.38E-05 1.875 0 Actinobacteria Thermoleophilia 0319-6M6 UNKNOWN 0.005

OTU1155 0.000767 20.875 5.625 Actinobacteria Thermoleophilia Solirubrobacterales 0319-6M6 UNKNOWN 0.002

OTU294 0.001058 32.875 15.75 Actinobacteria Thermoleophilia Solirubrobacterales 288-2 UNKNOWN 0.033

OTU2691 0.000177 4.125 1.375 Actinobacteria Thermoleophilia Solirubrobacterales 480-2 UNKNOWN 0.036

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OTU670 0.000225 5.375 1.125 Actinobacteria Thermoleophilia Solirubrobacterales Elev-16S-1332 UNKNOWN 0.008

OTU27076 0.000103 2.25 0.625 Actinobacteria Thermoleophilia Solirubrobacterales Patulibacteraceae 0.045

OTU2132 0.000334 7.625 1.125 Actinobacteria Thermoleophilia Solirubrobacterales Solirubrobacteraceae 0.009

OTU2202 0.000167 4.25 1.25 Actinobacteria Thermoleophilia Solirubrobacterales UNKNOWN UNKNOWN 0.024

OTU20834 0.000263 5.75 0.625 Actinobacteria Thermoleophilia Solirubrobacterales UNKNOWN UNKNOWN 0.004

OTU1671 0.000592 13.375 1.625 Actinobacteria Thermoleophilia Solirubrobacterales UNKNOWN UNKNOWN 0.004

OTU6183 8.75E-05 1.75 0 Actinobacteria Thermoleophilia UNKNOWN UNKNOWN UNKNOWN 0.03

OTU1950 8.75E-05 2.5 1.125 Actinobacteria UNKNOWN UNKNOWN UNKNOWN UNKNOWN 0.032

OTU625 0.000166 3.375 0.375 Sphingobacteriia Sphingobacteriales Chitinophagaceae Flavisolibacter 0.024

OTU290 0.000178 3.75 0.5 Bacteroidetes Sphingobacteriia Sphingobacteriales Chitinophagaceae Flavitalea 0.038

OTU5580 0.000119 2.375 0 ML635J-21 UNKNOWN UNKNOWN UNKNOWN 0.021

OTU5011 0.000188 3.75 0 Cyanobacteria UNKNOWN UNKNOWN UNKNOWN UNKNOWN 0.028

OTU13636 0.000547 11.875 1.25 Bacilli Bacillales Alicyclobacillaceae Tumebacillus 0.005

OTU1519 9.53E-05 2 0.25 Firmicutes Bacilli Bacillales Paenibacillaceae Cohnella 0.005

OTU15601 0.000122 2.875 0.625 Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae Gemmatimonas 0.024

OTU3603 0.000488 11.25 3.375 Gemmatimonadetes Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae Gemmatimonas 0.032

OTU87 0.000684 19.75 7.75 Gemmatimonadetes Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae Gemmatimonas 0.024

OTU2582 0.000139 3 0.375 Gemmatimonadetes Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae UNKNOWN 0.018

OTU680 0.000216 4.5 0.25 Alphaproteobacteria Caulobacterales Caulobacteraceae Brevundimonas 0.011

OTU1 0.003589 207.5 145.625 Proteobacteria Alphaproteobacteria Rhizobiales Bradyrhizobiaceae Bradyrhizobium 0.028

OTU986 0.000194 4.875 1.25 Proteobacteria Alphaproteobacteria Rhodospirillales DA111 UNKNOWN 0.008

OTU4584 0.000125 2.5 0 Proteobacteria Alphaproteobacteria Sphingomonadales Sphingomonadaceae Sphingomonas 0.006

OTU17941 0.000269 5.75 0.5 Proteobacteria Alphaproteobacteria Sphingomonadales Sphingomonadaceae Sphingomonas 0.009

OTU8 0.011164 342.125 122 Proteobacteria Alphaproteobacteria Sphingomonadales Sphingomonadaceae Sphingomonas 0.002

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OTU14988 0.000511 12.375 2.625 Proteobacteria Alphaproteobacteria Sphingomonadales UNKNOWN UNKNOWN 0.007

OTU5833 0.006244 208.5 101.5 Proteobacteria Betaproteobacteria Burkholderiales Burkholderiaceae Cupriavidus 0.014

OTU13937 0.000883 30.875 18.25 Proteobacteria Betaproteobacteria Burkholderiales Comamonadaceae UNKNOWN 0.042

OTU4921 0.000117 2.375 0.5 Proteobacteria Betaproteobacteria UNKNOWN UNKNOWN UNKNOWN 0.046

Table S8. SIMPER results for bacterial OTUS that differ between the germinant-associated live microbial inocula (rhizosphere and bulk) in drought versus ambient conditions with Weighted Unifrac distance metric. OTUs with significantly greater average percent relative abundance in the drought than ambient soils are presented (p < 0.05). Percent dissimilarity explained refers to the amount of community dissimilarity between the ambient- and drought-exposed bacterial communities that a particular OTU explains. Rows organized by taxonomy and unadjusted p-value presented.

Avg. % Avg. % Percent rel.abund. rel.abund. Unadjusted dissimilarity under under OTU explained drought ambient Phylum Class Order Family Genus P-value

OTU637 0.0004 10.75 4 Acidobacteria Acidobacteria Subgroup_3 UNKNOWN Bryobacter 0.04

OTU15625 0.0001 2 0.375 Acidobacteria Acidobacteria Subgroup_6 UNKNOWN UNKNOWN 0.047

OTU462 0.0003 7 1.75 Actinobacteria Acidimicrobiia Acidimicrobiales Acidimicrobiaceae CL500-29_marine_group 0.01

OTU1439 0.0001 1.25 0.125 Actinobacteria Acidimicrobiia Acidimicrobiales UNKNOWN UNKNOWN 0.048

OTU851 0.0004 8.875 2.625 Actinobacteria Acidimicrobiia Acidimicrobiales UNKNOWN UNKNOWN 0.048

OTU27784 0.0001 2.375 0.25 Actinobacteria Actinobacteria Frankiales Geodermatophilaceae Geodermatophilus 0.022

OTU7549 0.0002 3.5 0.25 Actinobacteria Actinobacteria Frankiales UNKNOWN UNKNOWN 0.024

OTU6546 0.0003 6.375 0.875 Actinobacteria Actinobacteria Frankiales UNKNOWN UNKNOWN 0.009

OTU10 0.0015 61.375 33.25 Actinobacteria Actinobacteria Micrococcales Micrococcaceae Arthrobacter 0.008

OTU2026 0.0001 1.875 0.125 Actinobacteria Actinobacteria Propionibacteriales Nocardioidaceae Nocardioides 0.033

OTU24762 0.0002 4.75 0.25 Actinobacteria Actinobacteria Propionibacteriales Nocardioidaceae Nocardioides 0.032

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OTU6394 0.0004 12.75 5 Actinobacteria Actinobacteria Propionibacteriales Nocardioidaceae UNKNOWN 0.018

OTU478 0.0005 10.625 2.625 Actinobacteria Thermoleophilia Gaiellales Gaiellaceae Gaiella 0.045

OTU745 0.0001 2.5 0.25 Actinobacteria Thermoleophilia Gaiellales UNKNOWN UNKNOWN 0.04

OTU18149 0.0002 5 1.375 Actinobacteria Thermoleophilia Gaiellales UNKNOWN UNKNOWN 0.046

OTU55 0.0006 18.875 6.375 Actinobacteria Thermoleophilia Gaiellales UNKNOWN UNKNOWN 0.011

OTU1155 0.0009 19.375 2.125 Actinobacteria Thermoleophilia Solirubrobacterales 0319-6M6 UNKNOWN 0.001

OTU294 0.0011 33.125 15.125 Actinobacteria Thermoleophilia Solirubrobacterales 288-2 UNKNOWN 0.011

OTU27076 0.0002 4.125 0.875 Actinobacteria Thermoleophilia Solirubrobacterales Patulibacteraceae Patulibacter 0.048

OTU16047 0.0002 3.75 0.25 Actinobacteria Thermoleophilia Solirubrobacterales Solirubrobacteraceae Solirubrobacter 0.004

OTU1710 0.0004 11.375 5.125 Actinobacteria Thermoleophilia Solirubrobacterales Solirubrobacteraceae UNKNOWN 0.025

OTU1308 0.0001 3.25 0.75 Actinobacteria Thermoleophilia Solirubrobacterales YNPFFP1 UNKNOWN 0.026

OTU2357 0.0003 6.375 1.125 Actinobacteria Thermoleophilia Solirubrobacterales UNKNOWN UNKNOWN 0.042

OTU1671 0.0005 10.5 1 Actinobacteria Thermoleophilia Solirubrobacterales UNKNOWN UNKNOWN 0.003

OTU719 0.0008 17 2.625 Bacteroidetes Sphingobacteriia Sphingobacteriales Chitinophagaceae UNKNOWN 0.014

OTU100 0.0008 29.375 14.5 Bacteroidetes Sphingobacteriia Sphingobacteriales Chitinophagaceae UNKNOWN 0.026

OTU2777 0.0001 1.375 0.25 Ktedonobacteria C0119 UNKNOWN UNKNOWN 0.024

OTU20260 0.0001 2.5 0.375 Chloroflexi Ktedonobacteria C0119 UNKNOWN UNKNOWN 0.047

OTU19384 0.0001 1.625 0.25 Chloroflexi TK10 UNKNOWN UNKNOWN UNKNOWN 0.039

OTU1963 0.0001 1.25 0 Chloroflexi UNKNOWN UNKNOWN UNKNOWN UNKNOWN 0.021

OTU1964 0.0005 10.375 0 Firmicutes Bacilli Bacillales Alicyclobacillaceae Tumebacillus 0.03

OTU520 0.0022 52.625 8.125 Firmicutes Bacilli Bacillales Alicyclobacillaceae Tumebacillus 0.002

OTU2208 0.0001 1.875 0.125 Firmicutes Bacilli Bacillales Bacillaceae Bacillus 0.021

OTU4544 0.0003 7.625 2.625 Firmicutes Bacilli Bacillales Bacillaceae Bacillus 0.033

OTU824 0.0002 3.75 0.5 Firmicutes Bacilli Bacillales Paenibacillaceae Paenibacillus 0.002

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Clostridium_sensu_stricto_1 OTU1206 0.0002 3.5 0.125 Firmicutes Clostridia Clostridiales Clostridiaceae_1 3 0.01

OTU874 0.0001 2.875 1 Gemmatimonadetes Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae Gemmatimonas 0.013

OTU68 0.0007 29 16.5 Gemmatimonadetes Gemmatimonadetes Gemmatimonadales Gemmatimonadaceae UNKNOWN 0.028

OTU20587 0.0001 2.375 0.625 Proteobacteria Alphaproteobacteria Rhizobiales UNKNOWN UNKNOWN 0.038

OTU17512 0.0001 1.875 0 Proteobacteria Alphaproteobacteria Sphingomonadales Sphingomonadaceae Sphingomonas 0.03

OTU14988 0.0003 8.125 1.25 Proteobacteria Alphaproteobacteria Sphingomonadales UNKNOWN UNKNOWN 0.001

OTU5833 0.0037 145.375 103.375 Proteobacteria Betaproteobacteria Burkholderiales Burkholderiaceae Cupriavidus 0.029

OTU74 0.0020 59 28.5 Proteobacteria Betaproteobacteria Burkholderiales Oxalobacteraceae UNKNOWN 0.036

OTU15951 0.0008 18.25 5.875 Proteobacteria Gammaproteobacteria Pseudomonadales Pseudomonadaceae Pseudomonas 0.049

OTU4 0.0650 1714.63 575.5 Proteobacteria Gammaproteobacteria Pseudomonadales Pseudomonadaceae Pseudomonas 0.01

OTU1527 0.0002 5.375 1.125 Spartobacteria Chthoniobacterales DA101_soil_group UNKNOWN 0.025

OTU7469 0.0002 3.25 0.25 UNKNOWN UNKNOWN UNKNOWN UNKNOWN UNKNOWN 0.003

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SUPPLEMENTAL FIGURES

Figure S1. Effect of precipitation and microbial treatment on gravimetric moisture content. Values were averaged from the germinant and seedling soils. Error bars represent ±1 standard error from the mean, numbers indicate replicates for each treatment. Horizontal bars and asterisks represent significant pairwise differences, * p < 0.05.

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Figure S2. Soil ammonium and nitrate differences among initial microbial treatments prior to experiment (A, D) and the effect of precipitation and microbial treatment on seedling- (B, E), and germinant-associated (C, F) soils. Error bars represent ±1 standard error from the mean and numbers indicate replicates analyzed for each treatment. Horizontal bars and asterisks represent significant pairwise differences, * p < 0.05, ** p < 0.01, *** p < 0.001.

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Figure S3. Effect of precipitation and microbial treatment on switchgrass seedling responses: A) root:shoot ratios given survival, and C) rhizosheath soil mass. Error bars represent ±1 standard error from the mean and numbers indicate replicates analyzed for each treatment. Horizontal bars and asterisks represent significant pairwise differences, * p < 0.05, ** p < 0.01, *** p < 0.001.

Figure S4. Effect of precipitation and microbial treatment on switchgrass germinant responses: A) root:shoot ratios given germination, and C) total biomass given germination. Error bars represent ±1 standard error from the mean and numbers indicate replicates analyzed for each treatment. Horizontal bars and asterisks represent significant pairwise differences, * p < 0.05, ** p < 0.01, *** p < 0.001.

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Figure S5. Differences in A) dissolved organic carbon (µg C per g dry soil) and B) microbial biomass carbon (µg C per g dry soil) among microbial treatments for ambient-exposed, seedling-associated soils only. Error bars represent ±1 standard error from the mean and numbers indicate replicates analyzed for each treatment. Horizontal bars and asterisks represent significant pairwise differences, * p < 0.05, ** p < 0.01, *** p < 0.001.

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Figure S6. Weighted Unifrac NMDS representing differences between initial soil inocula (black) and final bacterial community composition driven by precipitation (drought – red or ambient – blue) and microbial treatment (bulk soil – circle, rhizosphere soil – triangle, autoclaved soil - diamond) for switchgrass A) seedling- and B) germinant-associated bacterial communities. Pairwise Weighted Unifrac distances between final seedling- (C) and germinant-associated (D) bacterial communities in bulk (circles), rhizosphere (triangles), and autoclaved soil (diamond) compared to the initial soils after exposure to ambient (blue) and drought (red) precipitation treatments. Each point represents the dissimilarity from each rhizosphere or soil block (n = 1 sample) to the initial soil from the same block at the start of the experiment. Bars represent ±1 standard error from the mean of each treatment # p < 0.10, * p < 0.05, ** p < 0.01, *** p < 0.001.

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Figure S7. Relative abundance of from A) initial live soil inocula and final B) seedling- and C) germinant- associated soils across all microbial and precipitation treatments.

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