How does weed killer get INTO the plant (leaves? roots? stem? mechanism?)
After cutting a 500-yard long path through thick poison oak, I'm now applying huge amounts of glyphosate-based Roundup weed killer to kill remaining emergent plants left behind after the battle.
These constant skirmishes are depleting my Roundup, gallon by expensive gallon (bought in concentrated bulk from Costco).
I'm spraying the stems, the ground, and the leaves ... but ... I wonder ... what is the mechanism that allows UPTAKE of the glyphosate?
I looked up how weed killers kill, and can easily ascertain that glyphosates mimick the natural EPSP Synthase needed as a catlyst for the plant to create proteins ... but nothing I've found so far tells me how the glyphosate is ABSORBED into the plant and WHERE it is best applied (leaves?, stem?, roots?).
Mostly, I'm left with huge tangles of poison-oak stems ... so I ask ... WHERE does weed killer get INTO the plant and how?