Banksia seminuda - River Banksia

The River Banksia is one of the largest growing banksias, reaching 50-60 feet tall with a straight trunk. This one has been limbed up, my hunch is to keep people from sleeping under. 

One of many beautiful specimens at UCSC arboretum.

Leaves are evergreen, alternate, simple, 3-5" long, narrow, leathery, dark green upper and white lower surfaces, margins light serrated.

Looks good from underneath.

Flowers in the fall, red/orange flowers in 8" long by 3" wide inflorescences with hundreds of individual flowers in pairs. Flowers can also be yellow, UCSC arboretum was selling some last year.

Fruits are aggregated into woody clusters looking like a cone. Few flowers actually produce fruit. Those that do are larger and when they open remind one of clams. Love the coloration of the "cone".

Remnants of the flowers with no fruit maturing.

Bark is interesting, fissured, orangish and gray.

Misidentification:
Other Banksias I guess. I have seen B. integrifolia around quite a bit, but they have smaller clusters of flowers, and not orange.

Location
Santa Cruz
1111A River Street (Highway 9)

Erythrina caffra - Coral Tree

The Coral Tree is a medium sized deciduous (Semi-evergreen) tree growing in a rounded spreading habit to 30-35' tall and wide. Typically looses its foliage mid winter. Damaged by cold weather. 

Leaves are alternate, trifoliate, each leaflet dark green, rhomboid to ovate shaped, with a somewhat elongated tip. The base can be more flattened resulting in a deltoid shape. Leaflets 2-5" long, laterals smaller that the terminal. Prickles (sometimes called thorns) along the mid vein.

Stems are stout, green when young, and usually covered with shape prickles, usually dark colored. Leaves can be clustered at the tips appearing whorled.

Flowers are beautiful and very tropical looking. They are orange - scarlet red, 2" long, about 1" wide and borne in a 1' long panicle.

Fruit is a pod with constrictions between the bright red seeds. I have not seen them set fruit here, these pictures were taken in SLO.

Older stems and bark is pretty cool. Often multi stemmed, light tan color with shallow ridges.

A variegated species, seen in warm climates only.

Misidentification:
Could be E. crus-galli the cockspur coral tree, but they have narrow trifoliate leaves. You can see one of these at city hall or in the Salvia garden at Cabrillo.

Location:
Santa Cruz
Floral Park  - Pleasure Point - 3 trees
3020 Pleasure Point Dr.
115 Toledo - very large specimen

Grevillea robusta - Silk Oak

Wow, can you believe the color of those flowers? What other tree has that color orange? The silk oak is plan looking tree until they start flowering (middle of May to June here) and then you can't miss them. Reported to reach 75 feet quickly, I think we might see 45-50'.  They didn't plant one at the arboretum because they are known to be weedy. They have an oval to pyramidal habit with short thick horizontal lateral branches. Evergreen, blooming in June around here.

The leaves look like so many other Grevillea species, they have sort of a ferny look to them but they are not soft. They are alternate, pinnately compound,  8 - 10" long, with 11-23 deeply dissected leaflets, light gray green with silver lower surfaces (one of the common names is silver oak).

Stems are silky when young covered with short rust colored hairs.

The flowers are yellowish orange arranged in 5-7" long clusters.  Individual flowers are in pairs on short stalks. The color comes mostly from the reproductive parts. 

The racemes are one sided, all the flowers facing upwards.

Bark is nothing special.

Misidentification: Not likely

Locations
Aptos:
3201 Merrill St, about a dozen planted on the perimeter of a housing development

Soquel:

3455 Maplethorpe Ln. Two nice ones flanking the driveway.

Santa Cruz:
Corner of Mission and Chestnut Extension.
441 High St.
902 Hanover. In Back yard but very visible.