Damsons is a subspecies of the plum which have a tart taste that is often used for culinary purposes such as making fruit preserves.
Most are too tart to be eaten raw from trees but there are some varieties such as the Merryweather that can be eaten directly from the tree. But most varieties are only used in cooking.
So can guinea pigs eat damsons, and if they can, how much can they eat?
This is the best nutritional info I can find, and this is limited at best.
PRINCIPAL NUTRITION VALUE IN gm/ mg
Vitamin c 9.5 mg
Fiber 1.4 gmc
Protein 0.70 gm
Phosphorous 16 mg
Potassium 157 mg
As you can see they do contain some phosphorus but also a nice amount of vitamin c. However they are 70% water.
Damsons are known to cause upset tummies if eaten too much, so personally I would be wary of feeding them to guinea pigs particularly with the lack of information on them.
There are definitely better fruits for them to eat which you can check out on the site here.
However, if you have any experience of your piggies eating damsons, then share them below. It would be great to hear from you.