This fruit is from either from a wild plum tree (Prunus americana), or else from an ordinary plum tree gone feral. More likely the latter, since California doesn’t appear to be in the natural range for wild plum.

In any case, the tree from whence came this plum grows in a ditch/creek bed along a 2 lane highway, and I’ve been watching it for weeks, hoping to collect a few of the ripe, purple fruits for planting out in the food forest. Until yesterday the tree was laden with them, but this morning I noticed that nearly all of the plums had vanished.  I pulled over and collected the last few – tracks all around in the mud under the tree lead me to believe that raccoons have been feasting, and I feel lucky to have gotten any at all.

Most “domesticated” plums are grafted, but I’m fairly certain that the one from which I gathered the plums is not, given its location and the age and appearance of the trunk.  I separated the pits from the small fruits, and will plant two in a pot and two directly in the ground, and leave them to weather the elements this winter.  Hopefully by spring one or more will have germinated, and they can take their place in the food forest.