Wicked quiddity

Liquidity.  Over a year ago, I noticed a waxy residue, sticky as pitch, glazing my sagging, browning fern.  Turns out the culprits are scale insects: tiny bodiless (or headless) parasites which siphon sap with a nightmarish, toothed/hooked protrusion.  Their discrete individualities are undeserving of the plural: they’re really one colony, making my job as exterminator as difficult as that of a social reformer: there’s no heart at which to strike, no regular pulse to monitor.  It’s infested my fern and broken my will.  I was told scales are pesky, but nothing I do eradicates them.  I know deep in my heart of hearts there is a substance that would decimate the scales and leave the plant unharmed.  I think there’s such a substance for everything.  Looking at my fern, still dwindling after so many amputations, and imagining the hideous non-existent faces of the ovular bugs, slurping down the plant’s life-force, I conceptualize the quiddity of a thing as that which is undone by that substance, the substance which kills it instantly and otherwise doesn’t nick a fly.  Hence, the essence: uniquely destructible yikes.