Answer:
The answer will depend a lot on what level of discourse is taking place in your class. I'll explain below.
Step-by-step explanation:
In the most basic sense, we understand that a wheelbarrow was essential for most early 20th century farming practices. For a farmer, his entire livelihood and the food supply of his community would depend upon that wheelbarrow.
The issue here, however, is that nothing depends upon this red wheelbarrow. The implication in the lines "glazed with rain / water / beside the white / chickens" is that the wheelbarrow is not being used, and has not been used in some time.
The most essential element to much of the Imagist poetry of W.C.W. is in his mantra, "No ideas but in things." His concern isn't with conveying the importance of the wheelbarrow at all—it's with delivering a concrete portrait of life grounded in reality.
When asked, "What depends upon the red wheelbarrow," the most correct answer, honestly, is "It doesn't matter."