Years ago I had a dispenser for liquid weed killer that I would like to find again: hollow plastic pole about 3 or 4 ft long,held upright so that pressure on the downward tip would push in the plug, dispensing liquid on top of the weed you wanted to kill. Let go & the tip/plug went back down to the tip of the pole so that no more liquid was dispensed. Anyone know where I can find one?

That was a long time ago and went under various names ,like weed eater, weed wick,weed stick
it was discontinued following a court battle with the makers of round up-- something to do with patent rights or product used as the active ingredient
It was a good idea as it put the poison directly onto the plant
you find one on e-bay or gumtree or find a small suburban hardware store that may be able to help with a source
the alternative is to get a pressure bottle that you can fill with weed poison that has a long wand with the control trigger at the top
turn the wand jet at the lower end to stream ( almost falling off ) and place the wand jet near the plant and give a quick blip of the trigger

No have no information on this.