Which of the following is a method to treat freshly cut stems and stumps of woody species?

The method of using a systemic, oil-based herbicide is effective for treating freshly cut stems and stumps of woody species because these herbicides are designed to be absorbed by the plant's vascular system. When applied to the cut surface of a stump or stem, the herbicide is taken up into the plant, disrupting growth processes and leading to the eventual death of the plant. This method helps prevent sprouting and ensures that the plant does not recover.

Using other methods such as applying liquid fertilizer does not target the underlying issue of regrowth in woody species. Fertilizers are intended to promote growth, not control it. Watering daily for one week could help support plant health but does not address the need to prevent re-sprouting after cutting. Covering with mulch may assist in providing some level of soil protection and moisture retention, but it does not have the systemic effect necessary to impede the growth of the cut plant. Thus, using a systemic, oil-based herbicide is the most effective and appropriate choice for treating freshly cut stems and stumps.