My daughter has a small tree in her back yard that has this fruit/nut?? It has leathery skin that resembles a bosc pear. The outer husk contains a huge seed or fruit with two lobes. As soon as my grandson cut it open, it has started to swell up as though it will pop out of the husk. I have never seen a tree like this or the fruit no less. Can someone enlighten me?
If it were growing here, I'd immediately say that it's a member of Aesculus, a buckeye or horsechestnut. In CA, it could be that or maybe other things I have never seen.
If the plant has opposite arrangement of branching and leaf attachment, and palmately compound foliage, then it probably is a buckeye. It could be the native Aesculus californica.
Have the two seeds turned any other color since the husk was cut through? They should mature to orangey brown in color. These (as with most Aesculus) are not fit for human consumption, but are awful fun to play with.
Many thanks to all of you for the responses, which got me pointed in the right direction and it looks to be the California Buckeye, Aesculus californica. I lived in Ky and visited Ohio many times, but can't say I ever saw a buckeye, which apparently is somewhat different that the CA native. 8-) Janet