Chiggerex. For prevention you can put a flea collar around each boot. Im always in tall grass at work an used to get chiggers alot. A co worker told me about the flea collar trick and it works.
To prevent them in the first place get some REPEL with permetherin in it. Permetherin is actually a nerve agent so you spray the stuff on your clothes and boots. It will kill the chiggers, mosquitoes, ticks etc. as they crawl across your clothes. Great entertainment on stand to see the mosquitoes land on your clothes and then die there. There used to be a product out called permenone that had permitherin in it too. It has a mild smell that goes away as it dries so put it on and then your cover scent. It will last through several washings too.
Only thing that helps chigger bites is time. Anti-itch oinments help get you through the day, but only time makes them go away. I love chigger threads as there is always a whole lot of misinformation thrown around.
As for preventative, sulpher powder in the socks, etc works, but its hard to find. Mesquito spray with deet (i.e. Off, Cutter, etc) works good too, but obviously not for hunting time due to oder. You don't need to spray head to toe, but really just around your socks and sleeves. Another note is that often chiggers are latched onto tree limbs and brush and climb onto you when you brush up against these objects. You are most susceptible to get them when clearing brush, etc. A good way to avoid them is to stay out of heavy brush.
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