It's impossible to say who specifically measured the mass of soil in which a plant grew without more context. This kind of measurement could be done by anyone involved in:

* Agriculture and farming: Farmers or researchers might measure soil mass to understand nutrient content or track soil loss.

* Horticulture and gardening: Gardeners might measure soil mass when preparing a planting bed or to adjust soil composition.

* Plant science and research: Scientists could measure soil mass in laboratory experiments to study plant growth or nutrient uptake.

The measurement itself isn't particularly unique, so there isn't a famous scientist or individual commonly associated with it.

If you have more context about the specific experiment or situation, it might be possible to find out who did the measurement.