Mock strawberry Duchesnea indica aka Fragaria indica or Potentilla indica
I got quite excited when I discovered these fruits beside the compost bin: much larger than the usual wild strawberries, of which there are numerous plants around the garden, but with fruit the size of my little fingernail, hardly worth picking.
However, when I rinsed one of the fruit, the achenes all rubbed off unlike a real strawberry and when I cut into it, it seemed to consist of a nice scarlet rim filled with white pith. Googling “berries that look like strawberries” provided conclusive proof that these were not strawberries at all but mere snares and illusions – native to eastern and southern Asia but naturalised in parts of the USA, edible but with little overall flavour, to which I can attest having first checked that they are not poisonous. Apparently the leaves can be used as a poultice for skin conditions, not something I intend to try.
The flowers are yellow, differing from the white or pink of true strawberries. They look somewhat like the cinquefoils which is possibly why I overlooked the plants at that stage.