Poison oak (toxicodendron diversilobum) is currently flowering on the west coast. In some areas, green berries are already starting to develop from female flowers like this one. You can see the ovary surrounded by petals stained with urushiol oil. You can tell that this plant has sustained damage because the oil has come to the surface, therefore, bumping into it could cause an unsuspecting hiker or walker to wake up with a nasty rash, a.k.a. contact dermatitis. Check out the Rash Plants app for photos of the rash and very useful info about remedies. Also visit the Rash Plants tab under Nature Education for poison oak, poison and sumac identification.
Two more Naturedigger apps are now compatible with the iPhone X! You can download the latest version of Horseshoe SOS just in time for spawning season (below), and Knotweed! just in time for... "oh no it's knotweed season!"
If you haven't checked out either app, they are full of great information and photos and definitely worth a look. They are free with no in-app purchases.
Spawning horseshoe crab pair