On my late May trip, I need to purchase some long underwear/base layers. All I have at this time is cheap Wal-Mart cotton blend stuff that isnt BWCA worthy!
So what are your recommendations? Mid-weight or light-weight? Silk, wool, or blends? Any brands? Thanks in advance!

I prefer merino wool.

Underarmor brand works for me. It is made out of polypropylene and wicks away the sweat. I would leave the cotton stuff at home.

I prefer wool long underwear. Best insulator and cheap too.

Silk and/or wool for me. Google 'The Underwear Guys'. They run some reasonable specials/clearance alot. They did have a cheap deal on some medalist polypro as well. Cabelas Bargain Cave has good stuff too. Just picked up some Polartec 200 fleece pants at Gander Mtn. this weekend because they were clearanced from 39 to 5. Sierratradingpost.com has a selection at discount as well especially if you want a tall size.

REI brand poly and spandex, I think they call it MTS,is good stuff. Keeps you warm and dry, doesn't absorb moisture, and doesn't carry the price that Patagonia, North Face or Under Armour does. The mid-weight is a good choice for Spring / fall conditions.

I have the REI MTS layer, Under Armor and wool base layers (Smartwool and Icebreaker). I prefer the wool layers. They don't wick the sweat away like the others but they are still warm when wet. Just don't leave them outside at night, the moths will eat them! With the MTS layer, they seem cooler and I can't get warm in them the same way. I am still new to the Under Armor so I can't say much for them yet.

Most running stores have tights for running that wick moisture away. They are warm, compact, and affordable.

If you are looking for a lower price go to Walmart or Target (The French discount Store) and look in the sports section. Just make sure they are moisture wicking.

wickers has some nice options, and sierra trading post carries them regularly at a good price. here you can see a medium weight thermax polyester zip neck top:

Wickers Long Underwear Top ($18.66)

in the summer months, a mid-weight zip mock turtleneck like this one is my cool weather insulating layer. versatile and easy.

good luck!

Merino wool here.

Man, you guys are quick with the recommendations! Looking at it, Sierratradingpost has an extra 20% off of $100, so I am thinking I will pick up a set of silks and a set of the wools (plus a random fleece I keep putting off buying). Then I can mix and match what I need.

I must say I am pretty surprised by all the different takes! I expected more of a consensus, but if we cant agree out or in, hanging or not hanging, we probably cant reach a decision on what to wear for underwear!

You'll do fine with all of these suggestions. The difference is for the most part is cost and personal preference. I favor polypropylene myself, but as has been mentioned there are cheaper choices than Under Armour. Look at Walmart, Kohls, and Target (or online). However, my kids are both quite heavily into school sports and the pressure is on to buy Under Armour. We've given in to them for some items, and I have to admit they are quality.

quote jbowden44: "...so I am thinking I will pick up a set of silks and a set of the wools (plus a random fleece I keep putting off buying). Then I can mix and match what I need.

Great idea. I've been teaching the Scouts for years how to layer their clothes when on a backcountry canoeing or backpacking trip and much of what you plan to do is spot-on, IMO.

A light base layer, not necessarily long johns, but a quick-dry short sleeve t-shirt, followed by a long sleeve quick-dry t-shirt that may be a little heavier (or not), and followed by a "warmth layer" (i.e. your fleece jacket). If you need a wind breaker, wear your rain jacket.

This gives you great flexibility with what to wear based on the weather of the day.

Polypropelene or wool.
I find the wool a bit better in the long run. The poly can get a little smelly and crinkly after a few seasons.

Under Armor all the way. Fits like a glove, warm and is awesome at wicking sweat. One of the best pieces of gear I have purchased.

I have a pair of polypro that I got about 15 years ago and they are still going strong. They wick away the moisture very well and they keep me oh so toasty. I think that before this deer season though I am gonna look into a new pair of the underarmor with the sent lock (or maybe after and get some sales).

I wear wool Icebreaker. Fleece works fine, however it is a bit bulky.

I'd highly recommend a non-cotton base layer. Wool is nice (doesn't retain smells as bad as polyester), but expensive. Polyester fills the same role, but will hold smells (possibly a concern if you are out for awhile--I personally don't care).

I would buy based on your activity level. If you are going to be active (i.e. portage a lot or paddle a lot) I'd get a mid weight for May. You can always strip off top layers. In camp you'll obviously want to layer up as you won't have as much activity. I have Patagonia (Capiline 3), REI (MTS), and Marmot base layers (not sure of model)--they are all good and would recommend any of them. Go with whatever is cheapest.

I like a half-zip style because you can vent some if you are hot and roll up the sleeves (Plus who doesn't like to show off manly chest hair?). REI's MTS is nice for this. Of the 3 I own, I probably wear the Patagonia most because it is the longest in the torso, but it is also the most expensive. Try them all on and see what FITS you best--nothing is worse than an ill fitting layer close to your skin. In camp bundle up with some fleece and if needed you can always throw on rain-gear over the top. I ice fish in my combo of rain gear and lots of fleece--plenty warm.

We go in late May. I take silk (thin packing), merino wool (lightweight), fairly thin nylon pants, and thin gortex rain/wind wear. In combos/layers this works for whatever weather comes. I air out/dry every chance and pack dry at night in tent. Wool is the only thing I've found that is warm even wet/damp if it comes to that. A set of fairly cheap poly wicking and microfleece did it until I chanced some wool on sale/clearance. My favorite lifesaver has been a hooded microfleece found on sierratradingpost called 'Brockway hoodie' by sportif usa. I don't like my arms or head in a mummy bag

You don't mention your budget. You could buy a quality set of silk, merino wool, and synthetic - or outfit a trip. I suggest that you buy a basic set of synthetic light/mid weight synthetics on sale somewhere (e.g. Sierra Trading Post)and venture out from there.

Cotton kills. Synthetics and wool blend synthetics have emerged as the optimal system.

I use both synthetic and merino wool. I prefer the merino wool just because it doesn't seem to retain odors. Both are much better than cotton though. Todd

You have so many decisions and choices. If your looking for some great deals, Target carries Champion active clothing that does everything you want it to. Is it the best? No, it's just plain functional without all the bells and whistles. And it doesn't say under armour, means you didn't over pay. UU is good stuff, just too pricey. Like buying North Face items, your paying too much to advertise for them.

I have a closet full of the highest tech clothing available. I have to, I sell it, and go through extensive training and updates on all kinds of active gear. Poly based products now come with metallic fibers that withstand odors. Take for example, my underwear is made by Exofficio. I tested these briefs on a BWAC trip. Wore them for 6 days without changing them, guess what? No odor. (I hope I don't get alot of ribbing from you guys for that) But I had to test them if I'm going to sell them. Needed the proof!

Anyway, Target sells a Champion baselayer top for $20.00 that is 92% poly and 8% spandex. Good blend, and it is brushed on the inside for comfort. I tested these, too. During the winter. Did great and was very impressed with the feel against the skin, which is important. It goes without saying, you get what you pay for, but sometimes you can pay too much.

I personally like synthetics. Less bulky, more movement, designed to layer, and pack well. In the BWAC, I always have heavy denim/canvas on the outside layer. So I can stay near the fire....

Cotton is not a good idea. Zero insulation when it gets wet. Sweat, water and rain, odds of that are pretty good.

Personally I'm a wool man. Most all my stuff is Smartwool, nothing against Ice Breaker, thats just what I bought. Very comfortable, wicks moisture and warm even when wet. Doesn't hold odors.

I have used Capilene in the past. It is less expensive and while it doesn't perform like wool IMHO it kicks the heck out of cotton. It will hold a funk like you won't believe. If you can't afford the wool Capilene is your next best choice.