Albizia julibrissin - Silk tree

The Silk tree or Mimosa tree is a fast growing small to medium deciduous tree commonly planted in Santa Cruz. Growing to 30' tall with an upright vase shape to a wide spreading umbrella habit, with horizontally layered branches on which the flowers are borne. Trees bloom in summer. They quickly lose all their foliage in fall and are late to leaf out. If you google Albizia you will see it's most common websites discuss its invasiveness.

Leaves are deciduous, alternate, bipinnately compound, 18-20" long, each of the 20 or so lateral leaflets is also compound with 40 to 60 tiny 1/4" long linear leaflets.

The shade created by the foliage is nice, as is the view up into the canopy.

Flowers are beautiful and one of the reasons people plant these trees. Again, like some others in the Legume family that don't look like peas. The attractive part of individual flowers are the stamens. Individually they are small, borne in large clusters in a branched inflorescence.

Fruit is a pod, about 4-6" long, flattened and tan color. Reasonably persistent.

Misidentification:
In flower not likely, however students have a hard time with just the foliage, looking a lot like Jacaranda mimosifolia. But the Albizia leaf is shorter, as are the leaflets.

Location:
Aptos
421 Clubhouse Dr.

Capitola
1540 45th Ave

Ceiba speciosa - Silk Tree

The silk tree is quite rare in Santa Cruz County. It's a medium to large semi-deciduous tree growing to 30-60' with a spread of about the same. Variable in form, some specimens are very broad while others tend to be more upright. Many examples I've seen south of SC are much wider than the images I have. Trees are unique with a large swollen trunk with prickles, large primary lateral branches upright but also can be going off in odd directions, (one of its common names is palo borracho = drunken stick). Beautiful in bloom. Formerly known as Chorisia speciosa.

Alternately arranged, palmately compound leaves, 6-12" diameter with 5-7 lanceolate to elliptic to oblanceolate leaflets each 3-5" long with slightly serrated margins. Petiole as long or longer than the leaf blade area.

Stems are covered with prickles, not spins, not thorns, but prickles. Usually dense when young, but as the trunk expands they tend not to produce more of them. I fell in love with this tree while attending Cal Poly. It was being grown by the department and I bought one and had it for years, actually leaving it in Petaluma with my in-laws while we went to Pullman for grad school, and it stayed there till they moved.

Flowers are pink with a light yellow or white throat, 5 thin petals, sort of lacy usually borne without leaves.

Fruit are oval to rounded pods 6-8" long opening up to reveal black seeds covered by cotton like hairs. Blooming in fall.

Green bark and stems, becoming gray with age.

Misidentification:

Hardly, with the stems covered with prickles. 

Location:

Aptos:

Corner of Rio Del Mar and Highland - Very nice tree

Capitola
4815 Crystal Ave is a small one.

4440 Opal Cliff Dr, 3 nice ones

Santa Cruz
City Hall has two of them.