Question
I would like to know the best way to kill poplars for fire wood.  That is to kill them and leave them standing for half a year or so.  The purpose is to allow them to dry/cure while standing.  Second is how to kill the poplar shoots that are in the garden and lawn.

Answer
Use what is commonly called the hack and squirt or frill method. In the frill treatment, the tree trunk is hacked or frilled at intervals around the trunk at a convenient level. Cuts must be through the bark and into the sapwood; chips remain connected to the tree to form a small cup. The cut frill can be treated any time of year (summer or fall is best), but the cut section should be treated with concentrated amine-formulated herbicide immediately after the frill is made. Few species require complete frilling. Spaced axe cuts with 0.25 tsp梬hich is about equal to one milliliter (ml) or cubic centimeter (cc) of undiluted water-soluble herbicide product per cut梐re usually adequate.
Use a hatchet and make cuts about 3 inches apart all the way around the tree trunk and use a squirt bottle and squirt Roundup undiluted in the cuts. The tree will take up the Roundup into the root system killing the tree and roots. You do not need to make the cut at ground level about 2-3 feet from the ground will work as good. This will mean less stooping over.

Sprouts can be killed in the lwan by wiping the foliage with Roundup.
Roundup will kill any green plant it gets on so spraying will kill the grass under the sprouts. Take a rag and wet it with the Roundup and wipe the solution on the foliage. I would wear plastic gloves to keep the Roundup off the hands due to the smell.