these pinch and pull bags work really well too, but a bit pricey 
Its kind of the reverse of what you’re talking about @TeddyNuggets 
For the pinch and pull’s, they have a little pocket you pour the pollen in and seal up. It’s attached to a string that hangs out the bottom of the bag. then put the bag over a branch or two, twist tie it closed, and pull the string to release the pollen inside the bag. shake the bag a bit, turn it upside down, whatever. Come back in 3-4 days and pull the bag off and all the pollen should be used up and/or inactivated (could also open the top of the bag and use a spray bottle of water to wet down the branches before removing the bag) and you won’t have any seeds anywhere else but those branches 