The photo of the leaf/leaves confirms that it is indeed a jacaranda. Mimosa leaflets are very evenly and uniformly spaced, while jacaranda leaflets grow randomly along the stem. Also, Mimosa leaflets are more rounded while Jacaranda leaflets are pointed. Here is a photo i just took of a small branch from my own jacaranda for you to compare. Click on the photo for a larger version.

lycopus Thank you for ID, and the willow with gall too. Greatly appreciated. Rina

I don't know what it is, but i cut one down on my property. It grew from seed and within two years, it was about 25 feet tall! I have seen them planted in parking lots here and also growing wild (not sure if native or introduced) in the foothills of the Sierra Nevada (Millerton Lake to be more specific).

To me, this sounds like it may not be a fern. Ferns don't have branches, first off. Also, there are tree-like plants among the ferns, but normally we call them tree ferns, not fern trees. There are a few non-fern trees that I've heard people refer to as "fern trees". Harrywitmore's suggestion to post a picture would be the easiest way to get help here. Otherwise, find a decent book on ferns that shows the names of the parts of a fern so you could maybe describe it a litte better, using the right terms. A two foot wide branch is pretty darned big for a six foot tall plant of any type ;) A picture is worth a thousand words...