wine secondary fermentation

Is secondary fermentation absolutely necesary for wine? I find that I don't need it for beer, and I'm curious if that crosses over.

Well, yes. In most of my wines, the primary lasts approximately 5 days or until the sg reaches 1.020 or so. Then, the wine is racked, and airlocked. I rack every 30-45 days as long as lees are present. The wine will generally finish dry and then is bulked aged in the carboy before bottling. In wine, there really is fermentation happening in the secondary, and it does serve a purpose. I guess you could keep it in primary longer, but that would probably leave the wine on the fruit/skins too long.

I think beer and wine are totally different in so many ways. Here's some reading on winemaking basics: http://winemaking.jackkeller.net/basics.asp

As a follow up, then. Is it important to do primary fermentation in a bucket or is a Carboy ok.

either is fine, as long as you stir daily in primary.

Stir? That's new to me, and I've read a couple of different sources. What is the stirring for?

Thanks for the help Yooper. As a fellow Michigander, I appreciate it

Many wines have you stir in primary- for a couple of reasons. One, sometimes fruit wines get a "cap" and that should be stirred back into the must so it doesn't dry out. Kind of like a beer krausen, but different!

Also, the must at this point needs lots of oxygen before getting to the business of finishing up the fermentation under airlock.

From Step 2 of the above link from Jack Keller:
Always begin fermentation in a primary, without an airlock, unless specially instructed to begin in a carboy. The inoculate (yeast culture added to the must) needs exposure to oxygen for the first 48-72 hours to assist the yeast in rapid reproduction and increase the population to a density suitable for rapid fermentation. If the must has been sulfited, they need the large surface area to take in the oxygen needed. The top of the primary need only be covered with a clean cloth of tight weave, such as muslin, held in place with an elastic band. If you have a primary with rigid lid drilled for an airlock, use the lid but plug the hole with a ball of cotton for the first few days.

Kits that do not contain grape skins or raisins or any other additives like elder flowers do not need stirring. If they do contain them then I recommend punching the cap down twice daily.