It depends on the seed. There are many different variety of seed that are able to grow where one method of planting it is to spread the seed over snow and let it melt down through. Check out this link: www.grassing.com/methods/index.html#Planting%20over%20snow There are however many warm weather variety of grass seed that don't perform as well and they too are mentioned in the above link.

Not if it's winter grass. For other grass seeds the snow itself does not harm but freezing temperatures will harm the seed. Planting over snow. Cool season grasses (Perennial Ryegrasses, Fescues, Bluegrasses) can be successfully planted on top of snow for winter planting. What happens is that the seeds are carried downward to soil level by melting snow in the spring. At that times cracks are present in the soil from the freezing temps of winter that the seeds can be "melted" into. This provides for reasonable seed / soil contact. The disadvantages are the same as for planting out of season above... a higher risk that this method may have some failures. http://www.grassing.com/methods/index.html#Planting%20early%20in%20season%20or%20out%20of%20season.

Probably not, but as usual it depends. What kind of grass, how long it was under the snow, if the seed has absorbed any water, and how deep in the ground it is. Cool season grass seeds, Perennial Rye, Fescue, Bluegrass, etc. are usually planted in the fall, most of the seeds sprout and get established before the snows but some seeds don't sprout until after the snows melt. Of course any grass that sprouts while covered with snow and before it can get any sun and establish itself is gonna die, but the unsprouted but viable seeds will not be harmed by the snow. In fact those grasses are sometimes scattered right on top of snow in the spring. This is a semi-successful practice. As the snow melts it waters the seeds and carries them down in the ground and into cracks that have opened by the freeze and thaw cycle. Often it can be warmer under a blanket of snow than on the surface, even seed laying bare on the ground can survive but some seed laying exposed over snow may not, especially if the snow goes thru some melting and refreezing. The seed absorbs some melt water then freezes, it is the ice crystals that form inside the seed that can damage it even if it hasn't begun to sprout. The warm season grass seeds, Bermuda, zoysia, St. Augustine and such have less of a chance of surviving but even then there is no definite answer. If the seed is in the ground it stands a better chance, if the seed isn't under the snow too long it may not be affected, especially if the snow melts before the grass sprouts. But no one is sure how long is too long, sometimes warm season seeds are planted in the fall, in hopes it will sprout and establish it self before it snows, but it snows sooner than expected, the seeds lay there all winter under snow and then sprout in the spring. Other times the seeds don't survive a couple of days of snow, especially if they have absorbed just a tiny bit of water but haven't even sprouted. Grass is a grain, or grain is grass, one or the other, and grain seeds are some of the toughest in the world. They can stay viable a long time if kept dry. Corn kernels from ancient Incan ruins, and Anazazi dwellings has been successfully raised. Barley from Egyptian tombs has sprouted. Away out here in the West the plains used to be covered with grasses that shed seeds all year long, some of the seeds slept under snow all winter and then sprouted. Even in Canada, and the Texas Panhandle, and there is nothing between the Panhandle and the North Pole but a two strand bobwahr fence and every winter some dang fool leaves the gate open and lets the North Wind blow thru. But the grass still grew. Some grass is so tuff it needs a prairie fire to crack the hull, others even need a freeze to crack the hull. So no definite answer, best thing is just wait and see if it sprouts, if not reseed. And then next winter lets make us a snowman and rub fescue seeds all over its head. It's the Hairclub for Snowmen! Frosty is not just the freezedent, he's a member. Until his member froze right off, I told that fool to close the gate.

Mine didn't. We seeded in August last year and the grass didn't really start to pop up until December because we had a mild winter. I think when the snow melted it just helped some!

Not crabgrass. And don't even ask about bermuda grass. these two defy the wrath of a sledge hammer!.