Final answer:
The Forest Service could potentially use its appropriation for 'Forest Protection and Utilization' to buy plastic litterbags as part of efforts to protect forest ecosystems from litter-related damage, aligning with the objectives of forest conservation.
Step-by-step explanation:
Under the necessary and proper clause, it is conceivable that a Forest Service could justify the expenditure of funds allocated for 'Forest Protection and Utilization' on plastic litter bags if they are considered necessary for the purpose of maintaining the cleanliness and overall environmental health of the National Forest. Since littering can pose a significant threat to forest ecosystems by affecting wildlife and the natural landscape, the provisioning of litter bags could be interpreted as a direct action towards forest protection.
However, this would depend on the specific legal interpretations and regulations guiding the appropriation of funds within the context of the Forest Service's mandate. The appropriation must be deemed both 'necessary' and 'proper' in the execution of the Forest Service's duties, which must be aimed at meeting the objectives of forest conservation and utilization.