I am all for pants, or trousers, whichever, and think that all hunters should wear them unless they are Highland Scots or Greeks.* Here some things I’ve learned about pants over the years.
There are few things worse than tight hunting pants. If your normal waist size is 36 and you buy 36 pants, by the time you finish tucking in longjohns, a couple of undershirts, and a heavy shirt, you’ll find your guts are constricted. Buy one size larger than the waist size you normally take.
Same with the inseam. When I was a kid there was a fashion for “stagging” your pants–having the legs chopped off an inch or so shorter than normal so the bottoms wouldn’t drag through the mud and the blood and the beer. What actually happened was, when you sat down, your shortened trousers hiked halfway up your legs so the wind could blow up and chill your nasty bits.
Buy your pants an inch or two longer than usual and tuck them into gaiters. Gaiters, as far as I’m concerned, are one of the great inventions of all time, ranking with air conditioning, the overhead-valve V8 engine, and the colostomy bag. Tuck your pants into gaiters and they will not drag in anything, nor will they flop around your ankles. Tuck them in so your pants bunch at the knee a little bit; that way, when you’re climbing, they won’t pull at your knees. I am embarrassed at the number of years it took me to discover gaiters. Get them in XL so they can accommodate heavy pants, and get quiet ones designed for hunting.
Ranking right up there with gaiters are suspenders, which I will not hunt without either. By the time you hang a knife or two, an ammo pouch, plus God know what else on a pair of weighty trousers, your belt will not support the load unless you cinch it up so tight that it will cause a stoppage between your large and small intestine, leading to fearful side effects. Hang stuff on your belt, but keep your pants up with suspenders. And here a product plug. I find that Filson suspenders rank head and shoulders above all others. Their elastic is strong; the leather button tabs are as stiff and unyielding as poker chips, and will stay that way while lesser tabs will loosen over time and slip off the buttons, leaving your pants down around your ankles.
Rainpants can be useful, but they do not have flys, by and large, leading to all sort of problems which I need not describe here. I think that Gore-Tex-lined wool pants, or something like that with a zipper, are a better solution.
*People who live in country that is mostly up and downhill have learned over time that conventional trousers can be pretty unhandy when you’re climbing. Thus, the Scots created the kilt and in the Balkans, Greece, and Albania, a kind of long skirt called the fustanella evolved. In Austria and Switzerland, people climb in knickers and long socks, which I think is preferable to a skirt. Switzerland is the only place I’ve ever seen where people spit shine their hiking boots.