Analyze how the speaker in the poem uses imagery to reveal their attitude towards power.

The dominant image in Marge Piercy's poem "A Work of Artifice" is a bonsai tree. The speaker of the poem describes the process through which a tree that, left in it's natural state, could have grown to majestic height is instead pruned and cultivated by a human gardener to remain stunted and dainty—a bonsai tree. She carries this imagery of the overly groomed and therefore limited tree throughout the poem and turns it into a metaphor for the way society oppresses women. The gardener in the poem has all the power, forcing the tree into his desired shape.

"Every day as hewhittles back the branchesthe gardener croons,It is your natureto be small and cozy,domestic and weak;how lucky, little tree,to have a pot to grow in."

These lines practically drip with irony. What the gardener is doing to the tree is anything but natural, yet he croons to the tree that "it is your nature." Taken as commentary about power, these lines draw attention to the way those in power believe and behave as though those without power are just naturally lesser, even as the empowered themselves are the ones taking that power away. It's a catch-22 of oppression.
Though the poem's diction is fairly conversational, the imagery is actually quite detailed. Note that it's not just the size of the tree that the gardener alters, but its natural habitat as well. The poem opens with the lines,

"The bonsai treein the attractive potcould have grown eighty feet tallon the side of a mountaintill split by lightning."

The contrast between "attractive pot" and "mountain" is extremely telling. One is domesticated, and, though "attractive," inherently constricting. The image of the mountain, however, is just as wild and majestic as the image of the tree climbing to eighty feet tall. From these very first lines, the poem sets up a dichotomy between the tamed and controlled and the wild and free.
It is not until the final lines of the poem that the imagery of that which is being oppressed changes from the natural to the human.

"With living creaturesone must begin very earlyto dwarf their growth:the bound feet,the crippled brain,the hair in curlers,the hands youlove to touch."

"Living creatures" is the first expansion of the subject of the poem from this one specific tree to a larger category, and the images that follow are of parts of the human, presumably female body. The speaker draws an inderect metaphor between the pruning of the bonsai tree and the beauty routines that society has imposed upon women: both are "dwarfing" their subject. It is in these last lines that the poem's message about power and oppression really becomes clear. Through constriction and domestication both the tree and women's power and freedom is stripped away from them.