I'm going to differ slightly from my learned colleagues here (Nolo and JimL), and recommend that you start using poles sooner rather than later. They are correct that poles are not absolutely necessary, and indeed, it can be fun and freeing to ski without them sometimes. Phil and Steve Mahre used to say that "If poles were half as important as most skiers think they are, we'd call the sport 'Poling.'"
They are not "important," but poles are useful for many things. Here are a few:
- Propulsion and maneuvering on the flats. Cat tracks, lift lines, crowded areas, uphill sections, and so on--this is where snowboarders often look at skiers with envy! Yes, you can skate and sidestep and "herringbone" your way around, but long skis not nearly as easy to maneuver in this way as ski boards.
- Timing. As jpski described above, in advanced skiing, poles aid timing and promote rhythm. Just swinging the poles smoothly, even without touching or planting them in the snow, works like a metronome for a musician.
- Precision. A pole touch/plant can help pinpoint the start of a turn. Looking ahead to where you are going to plant the pole is probably as important as the plant itself in this respect, but either way, a smooth pole swing and touch can help immensely in moguls and other situations where we need to ski a precise line.
- Commitment. "If you plant zee pole, YOU VILL TURN!" This ancient advice I once heard from an old Austrian instructor still rings true. A good, firm pole plant can be the key to making a turn in situations where you have doubts, where you are unsure of yourself. "Pole!--Pole!--Pole! . . ." Just saying the word loudly can get you through a series of bumps or down a steep pitch that might otherwise cause you to freeze up with panic or doubt.
- Stability. A good pole plant adds stability to the upper body in conditions that tend to rock us around--like bumps. It aids balance (or at least, imbalance), and helps keep the upper body from rotating out of control.
- Recovery. Probably goes without saying, but a well-placed pole can keep us from falling, and push us back into position when out of balance. The better you can recover, and the more confidence you have in your ability to recover, the more you will be able to push your limits, ski faster, and take reasonable risks.
- "Rotary." The classic "blocking pole plant" is not a "default movement" in modern skiing, which relies more on disciplined movements of the feet and legs to guide the skis, rather than a forceful, forward angled pole plant that transmits torque through the outstretched arm to the rest of the body and skis. But the blocking pole plant remains an important technical option for versatile skiing in all conditions. Good skiers use it more often than many instructors realize, especially in bumps and other situations requiring tight, short, quick turns. The blocking pole plant can turn the skis quickly, even when out of balance, and it also creates stability to prevent rotation or over-rotation, as described above.
- Liftline Tactical Weaponry. Sometimes you've just got to get aggressive to get through that crowded lift line. . . . Without poles in Europe, you could well end up standing at the bottom all day!
- Gesturing, drawing, and pointing the way. Sometimes I wonder how snowboard instructors even manage to teach at all!
Those are just a few of the uses of poles. That said, realize that they can cause more harm than good. Many skiers develop horrible habits with poles, and over-reliance on them is a common error. Don't let poles interfere with your arm and hand stance, which is probably natural and effective from your ski board experience (not to mention walking and running and balancing in general). Don't let them introduce gross new movements of your arms and upper body--effective pole swings come mostly from the hands and wrists, not the elbows, shoulders, or torso. Poles should only help. But don't use them as crutches, and don't let them interfere with the much more important good, disciplined movements of your feet and legs and the rest of your body.
Good luck! As Nolo and JimL suggest, it may be wise to make a run or two (or more) without poles as you adapt your ski board movements to the new, longer boards. But don't let it go too long! Get used to holding poles and carrying them around at first. Use them on the flats. Watch good skiers and, when it feels right, start to imitate their rhymic pole swings. If it feels awkward, stop using them for a few turns or runs, then ease back into it. They will help! Of course, if you want to make sure you're getting it right, find a good instructor to guide you to great pole use, and to make sure you're not just developing bad habits. Always a good decision!