Trees that grow in flood plains are susceptible to overturning. This is typically due to floodwaters exposing the tree roots (called soil scouring). Environmental engineers at Saitama University (Japan) investigated the impact of soil scouring on the characteristics of overturned and uprooted trees (Landscape Ecology Engineering, Jan. 2013). Tree pulling experiments were conducted in the floodplains of the Komagama river. Trees were randomly selected to be uprooted in each of three areas that had different scouring conditions: no scouring (NS), shallow scouring (SS), and deep scouring (DS). During the uprooting of the trees, the maximum resistive bending moment at the trunk base (kiloNewton-meters) was measured. Simulated data for five medium-sized trees selected at each area are shown in the table, followed by a MINITAB printout of the analysis of the data. Interpret the results. Does soil scouring affect the mean maximum resistive bending moment at the tree trunk base?

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None Shallow Deep 23.68 11.13 4.27 8.88 29.19 2.36 8.48 12.09 7.52 25.89 13.66 20.47 22.58 23.24 3.46 One-way ANOVA: MOMENT versus SCOURING Source DF MS SCCURING 2 528.5 264.3 5.40 0.021 12 586.9 48.9 14 1115.4 Error Total S- 6.993 R-Sa - 47.30 R-Sa(adj) - 38.61%