A Couple Questions about Thermals

[The Silence]

A have a couple thermal scenarios I would like to get your input on.

(1) I hunt in open farm country that has rolling hills associated with it. I've noticed that the deer movement really starts to pick up about the time the sun descents behind the hills and the areas become cloaked in shadows. 2 years ago I had a light southerly breeze coming up between 2 hillsides. I did some calling about the time the sun was fading over the hillsides. I heard a huge ruckus coming from the standing corn and out around the corner came a shooter at about 80 yards SE of me . He was all jacked up and ready to rumble. I thought, here we go, I got him right where I want him. The problem was, he never got any closer despite the fact that he wanted to come over and beat someone. He stood there for a good minute and then turned and slowly moved away. I thought, "What the heck?". I pulled some milkweed out and let em fly and to my surprise the thermals had overcome the slight breeze from the south and my scent was now blowing to the south. What surprised me was that I wasn't even set up on a hill, but the ground I was hunting on has a very,very slight slope running down to crop fields below. That wind switch occurred twice that year under the exact same circumstances. When you guys have a situation like this, and you only have a slight breeze blowing, do you normally wait until you have a stronger wind to overcome the thermals or do you assume the wind is going to flip and just set up differently.

(2) I have a couple sets that are located on the edge of smaller drainages that are typically 3-4 feet deep and about that wide. I want to access one of my stands via that drainage. Any ideas how wind reacts in this type of scenario. One of them is located in a strip of timber that runs E/W and the timber strip is ~35 yards wide while the other one runs N/S and has 2 strips of CRP running on either side of it that are both 40 yards wide. There are scattered trees along the drainage but not like a solid wall of trees.

I haven't hunted either one of these sets much so I'm trying to take an educated guess before I go in there the first time. I'm trying to stay out of these areas for the most part but I know I will need to get the milkweed out once I head in to hunt these places.

[oldrank]

Scenario 1. I would adjust my set until I was in a position where I felt confident the thermals would not jack up my hunt. I am banking on the buck exiting at thermal switch or after. It might take a few hunts to figure this out but you will gain the Intel for the future.

Scenario 2. I'm not sure I have hunted a similar condition so I will not give advice.

[Boogieman1]

For myself in scenario one I would set up to hunt the thermal instead of the wind. I wouldn't expect mature buck movement until after thermal reversal anyhow. Ethier wait until thermal drops late eve b4 getting in stand or hunt it with a wind that just doesn't blow into the bedding and have your thermal dropping ethier below them or they must pass you to get a whif.

Scenario 2 I hunt a lot of. A lot of variables in this one that takes some trial and error. Easiest answer wait until leaf drop and hunt it on sunny mornings. Else get above the movement hunt high and blow over them or follow the slope and get below them for evenings.

[dan]

I have section in the new farm DVD about how deer use thermals when entering fields... You have to set up in anticipation of the thermal. You ain't going to beat it.

As far as the canals go, it can be a little trickier. If one side has trees and one side is more open your going to get a vacuum effect on wind going over the trees thats going to suck your scent back into the woods on wind gusts so you would need to get away from the edge. When the wind comes from the open its going to redirect along the woods edge when it its it... The amount this happens will be directly related to how hard the wind blows and what the thermals are doing... Also, if there are trees on both sides and its an opening in the trees your going to get swirling. Good to play safe and stay back from the opening. Thermals from the water usually have a small pill of the water gets warm and then the air cools, if there is an opening down the canal it can pull the air current down the stream. If the water is colder than the air your scent can pool down by the water.

[Rich M]

I hunted a spot in SC where I set a stand on the far side of a 6-8 ft wide canal that ended in a pond to my left and went off into the woods to the right. That thing was a wind tunnel. The deer could not smell you no matter what direction the wind or thermals were flowing - it was amazing.

[headgear]

Absolutely plan for the thermal kicking in wind or no wind. No matter what the weatherman says about the wind i have seen it die at prime time and had thermals take over so you kind of always have to be ready for it. It does not take much to direct those thermals, a small 3-4 foot rise can be plenty to change the path of a thermal. I have one spot if I am a little too close my thermal gets sucked towards a bed, if i am 6-7 yards further back i gets sucked into a swamp behind me and there is a small middle zone where you get your milkweed pulling both ways.