Supplemental information:

Table S1. Description of the locations of 6 naturally occurring Arabidopsis thaliana populations in Extremadura, Spain.

Locality / Code / Year / Na / Elevation / Habitat Description / Rainfallb
Pizarro / PIZ_I / 2009 / 40 / 281 m / Disturbed roadside by / 554 mm
2010 / 30 / agricultural field. Full sun
2011 / 30
Pizarro / PIZ_IV / 2009 / 30 / 289 m / Disturbed roadside by / 575 mm
2010 / 30 / agricultural field. Full sun
2011 / 10
Campo Lugar / PIZ_V / 2010 / 30 / 308 m / Full sun area near olive grove / 595 mm
2011 / 30
Serradilla / SER_III / 2009 / 30 / 367 m / Full sun area near olive grove / 712 mm
2010 / 30
2011 / 33
Pago San Clemente / PSC_IV / 2009 / 35 / 595 m / Disturbed roadside. Full sun / 688 mm
2010 / 30 / with late afternoon shade
2011 / 30
Mérida / MER / 2010 / 20 / 232 m / Disturbed shallow soil in / 494 mm
2011 / 20 / urban center

a“N” refers to the number of individual plants measured for aboveground traits in each population in each year. bRainfall values are annual averages for each location obtained through on line source: http://opengis.uab.es/wms/iberia/en_index.htm.

Effect / Population / Year
Site / Year / PIZ_I / PIZ_IV / PIZ_V / PSC_IV / SER_III / 2010 / 2011
Phosphorus / <0.0001 / 0.43 / 68.5 (13.5)A / 82.0 (15.4)A / 57.9(7.3)A / 49.9 (2.0)A / 15.3(2.8)B / 57.3 (6.8) / 45.3 (5.6)
Nitrogen / 0.3 / 0.006 / 25.8 (6.03) / 33.2 (6.8) / 28.8 (4.3) / 20.4 (4.5) / 17.2 (2.5) / 29.9(2.6)A / 16.4(3.3)B
Potassium / <0.0001 / 0.86 / 189.9 (37.7)B / 143.7(23.5)BC / 175.8(16.8)B / 302.7(24.4)A / 82.3(13.3)C / 180.5(19.5) / 181.8(21.5)
Sodium / 0.04 / 0.04 / 30.2 (10.1)A / 18.1 (2.0)AB / 13.1(1.0)B / 18.0(3.1)AB / 26.3(2.5)AB / 23.5(3.6)A / 16.8(0.8)B
Calcium / <0.0001 / 0.05 / 678.4 (36.4)BC / 457.5 (70.8)C / 815.9(104.3)AB / 1039.8(82.6)A / 1075(63.4)A / 765.1(56.2)B / 961.2(68.6)A
Magnesium / <0.0001 / 0.0003 / 136.5 (13.3)B / 69.5 (10.4)B / 114.0 (23.5)B / 111.3(5.3)B / 261.8(32.6)A / 160.8(19.2)A / 113.8(9.4)B
Sulfur / 0.0007 / 0.9 / 8.6 (1.0)A / 7.3 (1.5)AB / 5.4 (0.6)B / 3.9(0.4)B / 5.1(0.5)B / 5.9(0.4) / 5.8(0.8)
Zinc / 0.001 / 0.0007 / 1.8 (0.4)B / 1.1 (0.2)B / 3.0(0.2)A / 1.6(0.3)B / 2.3(0.5)AB / 1.7(0.2)B / 2.6(0.3)A
Manganese / <0.0001 / <0.0001 / 11.5(1.8)A / 7.0 (1.1)AB / 5.8(0.5)B / 4.6(0.7)B / 10.7(1.4)A / 5.9(0.5)B / 11.0(1.1)A
Iron / 0.0005 / 0.72 / 52.5(6.7)A / 64.3(17.8)A / 21.5(3.3)B / 22.8(2.4)B / 38.6(6.4)AB / 36.4(5.6) / 38.8(4.0)
Copper / 0.02 / 0.95 / 0.8 (0.06)AB / 1.0(0.2)A / 0.61(0.05)B / 0.6(0.05)B / 0.8(0.1)AB / 0.7(0.06) / 0.7(0.05)

Table S2. Soil nutrient concentrations in ppm and analyses of variance for Extremaduran sites and year in the field. *Significant values (p<0.05) from two way analysis of variance (ANOVA) for site and year are highlighted in bold italics. Soil nutrient mean values are in ppm (one standard error of the mean). Soil samples per populations ranged from 6-10 samples per population. Capital letters group sites or years by statistically indistinguishable means following Tukey post-hoc tests. If ANOVA main effects were not significant, no post hoc tests were conducted.

Figure S1. Location of Arabidopsis thaliana field sites. Map with the location of the field sites with Arabidopsis thaliana populations in the region of Extremadura, Spain. Codes correspond to letters of the nearest town and the order in which populations were located relative to other populations in the area. Blue lines represent major rivers and orange/yellow lines indicate major roads.

Figure S2. Rosette trait variation in greenhouse-grown plants. a) Number of rosette leaves for each of four Extremaduran populations and the common laboratory line Col (CS60000) population grown in common greenhouse environment. b) Rosette diameter (mm) for each population grown in common greenhouse environment. Boxplot attributes as previously listed. Letters indicate post-hoc results where populations with corresponding letters are more similar.