I remember a few pesticide type questions that were not in the guide.
Also, your tree ID. They must have supplied you with a list - right
It could be twigs on a table, or photos.
Where in California are you?
I'm just over the north border in Applegate Valley. Seems I get into California by a few miles every week, whether its hiking in Red Buttes Wilderness or going down through the redwoods.
So - you like horses -
here's a photo I took along Crater Lake highway last week east of Shady Cove...