Agronomists observed that blueberry plots treated with crushed pecan shell mulch produced 25 percent higher fruit yields than untreated bare soil plots. The agronomists concluded that nutrients released into the soil by decomposing pecan shells caused the increase in yield.
True or False: The finding that blueberry plots covered with an inert synthetic ground cover—which provides identical moisture retention and weed suppression to pecan shells but releases zero nutrients—produced yields no higher than untreated bare soil plots strengthens the agronomists' argument.
Answer: Answer
Answer
True
The claim is evaluated as True because the supplementary finding functions as a negative control. By showing that the yield gain does not occur under identical non-nutritive physical conditions, the finding eliminates moisture retention and weed suppression as alternate causes, directly boosting the plausibility of the nutrient-based explanation.
Step-by-Step Solution
Key Concept
Strengthening a causal conclusion by ruling out alternative explanations through a control condition
Estimated Time:45s