What factor does NOT influence how well herbicides are absorbed by plants?

Herbicide absorption by plants is significantly influenced by the characteristics of the plant itself and the environmental conditions directly affecting the plant. Leaf thickness plays a role because thicker leaves may have a lower permeability, making it harder for herbicides to penetrate. Similarly, leaf moisture is crucial, as a higher moisture content can enhance herbicide uptake by creating a conducive environment for absorption.

Wind conditions, while they can affect how herbicides are applied and their potential drift, directly impact the concentration and delivery of the herbicide to the plant. Therefore, those options highlight factors that either enhance or inhibit the absorption process.

Soil temperature, however, primarily influences the herbicide's chemical activity in the soil and the overall metabolic processes of plants rather than affecting how well the herbicides are directly absorbed through the leaves. Soil conditions are more relevant during application phases rather than absorption characteristics of leaf tissues. Hence, it is the factor that does not directly impact the absorption of herbicides by the plant leaves.