the species you posted at 11:41 is Prionus heroicus which is almost black. The underside between the second and third legs of P. californicus is always light colored, P. heroicus is dark, sometimes almost black. P. heroicus may eat roots of grasses. Probably not a threat to your fruit trees.

I feel better about my apricot trees now. I dislike spreading any poison! They can have the grass, as far as I'm concerned. Bunch grass, mostly, and IMO, an invasive weed in my garden and desert yard. I am posting a couple pictures of the second, somewhat smaller specimen found in the same rain barrel. I suspect this one is also a male.

According to this they look very similar, but Prionus rarely get as big as 30mm, and this one is over 50mm. It also looks like Prionus is reddish, and this one is black. It does have 2 lateral spines on the pronotum. That said, they decided that specimen was a Prionus heroicus. I have another one that I thought was dead, but now seems to have revived from its drowning. I may chill it down and try to post more pictures. Should I worry for my trees?