When I was trapping and calling a large bird ranch some years ago, it was full of Russian Thistle trees, thick grease wood and heavy large sage brush, almost impossible to call in. Flat marshy areas with canals and ditchs you could not see being on the ground or even a foot or two high, was painfull, LOL
I used the russian thistles as a perch where I could but it always was a headache trying to see with the branchs. So I got me a tri legged archery stand that was about 8 foot tall and set it in front of the trees. I would set my speaker at the base of the stand or off to the side as far as the cord would reach, as at the time I was using a Johnny Stewart casstte caller, I owuld place the caller control in between my legs on the seat and keep the rifle ready, was a while to get me a system, But I drilled them dogs
Every thing change then, as I could see over the brush and notice all kinds of shooting lanes that one could not being down on the ground or half way up a tree in a crook.
Elevation is everything when dealing with brush with no hills or large trees to move up on. I would move the stand once a week to a different area of this ranch and then call for a week or so at different times of the day. It really made a difference in seeing dogs.
One should not count out a different method of another just cause they see no use for it, theres usually a reason for the trouble if you wait long enough for the whole story.