Fruit down by the River

I took Smoochi for a walk down by the River where I found a Tree full of this fruit. WHAT IS IT?

I saw lot's of Coot's, but by the time I got the Camera out they were gone :o(

I took photo's of different Foliage & flowers, but this one got picked, sorry it's a little blurry, trying to hang onto a dog's lead & take a photo can be tricky. LOL!