O wind, rend open the heat, cut apart the heat, rend it to tatters. (1-3)
The speaker's diction here is pretty violent. She wants the wind to "rend open" and "cut apart" the heat. She must feel pretty oppressed to use such fierce language.
Fruit cannot drop through this thick air— fruit cannot fall into heat that presses up and blunts the points of pears and rounds the grapes. (4-9)
The imagery in these lines is striking. We can see the direct effect of the heat on the fruit. And even if the speaker is being hyperbolic (also known as exaggerating), we feel her pain by way of these images. It's so stinkin' humid that even gravity is losing the battle against this weather.
Cut the heat— plough through it, turning it on either side of your path. (10-13)
Here's an example of the heat's objectification. H.D. describes it as something tangible that the wind can "plough" through. Do you see any hope in these lines? Do you think that the wind will come? Or is the speaker's apostrophe bound to fail?