I ordered seedlings from our DNR- I believe Northof50 has a good plan, I believe you get almost 20lbs of pits from 100 lbs of fruit.

Will squirrels dig them up??

You are spot on rogue, you’d be hard pressed right now where I live to find any coyote scat not loaded with pits.

Northof50
How long do plumb pits need to be frozen before they'll grow when planted?

The American plum is one of the greatest wildlife plants around. Even out here in the desert, give them half a chance and they will flourish, making habitat for pheasants, Bob white and sharpies. Whitetails and mule deer love them. After they are established they are bulletproof to drought, fire and accidental herbicide. And a bundle of them from a nursery costs about a buck each. Survival great. I bet I have planted around a half million of them over 25 years. Definitely do a taste test before picking for jelly. Some of my guys tried making wine out of them, actually it was quite good.

Out here we try to make thickets out of them. Once you have that they are impenetrable. Once they start spreading from roots, I like to start disking or rototilling around the thicket to get the sunflowers going (food right next to winter cover) every spring. Quail heaven!

How long do the seeds/ pits need to freeze?

The seed do better with 30 days of frost. ( but that lecture was 40 years ago)
our main problem now here is a seed weevil that gets in the pits and the plums drop too soon to mature, but the freezing does a number on the weevil, left on the ground the weevil matures and starts the cycle next year.
our thickets are a magnet during rainy days for Ruffed Grouse cover ( enough canopy to stay dry)
the squirrels find the big piles that are dropped by the bear dung in the fall during/ even with 3 feet of snow cover

plum curculio [i]Conotrachelus nenuphar[/i]

If those are the same thing as what we can Sandhill plums I bet I've sprayed and killed more than everyone on here has planted or will plant. They have there place but they will flat take over the grass land here if not managed. Probably have killed thousands of mulberry trees too.

Toka plum is a good cross pollinator.

A less invasive species is the Canada Plum Prunus nigra it does not sucker like the American plum, it is a woodland species, has rounded teeth on it's leaves and has a rounded stone vs a flat stone of the American and no sharp edges
it blooms about 5 days with flowers that turn pink from white after the American plum blooms

Is that weevil the reason som of my plumb pits have holes in them? And are those pit seeds now worthless?

I would be interested to know how those seeds do after being frozen. When I bought chestnut seed I was told not to freeze them but to put them in the vegetable drawer in a bag with sphagnum moss for three months and not to plant the seed with the seedlings as the deer, squirrels, mice ....... will dig them up and eat them . Look up stratification of nuts, it’s a process.

330 those with holes are worthless as the weevils have eaten the pith which is the food source of the growing seedling.

Yes mice and squirrels will dig up the seeds and eat them. Deer Mice chew little round holes in them and get the pith out with their long front incisors as do squirrels

I have had grey squirrels dig two year old walnut sapling out and eat the remaining pith......killing the tree

They'd probably be good in a fruit smoothie

With the price of fruit at the store I wish I would have planted my plum trees about 5 years ago