I'll chime in one more time on the wood moisture issue. Ideally you should use a moisture meter and check it before staining. But, I've never been able to get my paint stores or hardware stores to spend the $100 to get one for themselves or customers ( I tell them to rent it out). Ideally the moisture content should be 15% or lower. A higher content will not allow good penetration on the wood. If you take a cup of water and flick large drops on the wood across the deck, you can get an idea of if its ready to stain. If the drops 'bead up' the moisture content is too high, if the penetrate the wood -- its dry enough.
Several folks have mentioned letting it 'age' before staining, this is deceptive. As you can let it age--- however with unsealed edges the wood will still wick mositure over time. Maybe lots more moisture that when it was built depending on where you live and how much rain you get. Aging the wood also can allow it to dry out too much and start to warp. So, you need to be careful there.
If you really want to do the deck and do not want to worry about moisture you can use Cabot SPF. Its transparent and will last about 2 years-- however, it is a waterbourne product designed to be put on wet wood. You use SPF cleaner first, then the SPF. The deck must be wet to apply this product. The moisture allows for the stain to penetrate deeply and displaces the water via osmosis. Then the next restain you can use a heavier pigmented product for longer life.