Juglans regia - English Walnut

The English walnut, from the Himalayas', is the commonly eaten walnut. It's a fast growing medium sized deciduous tree, often planted as a shade tree. Mature trees can be up to 60'. They form a rounded to oval canopy. Branching low on the trunk the main laterals are upward arching and massive in size.

Fall color is yellow, can be pretty nice but often not.

Leaves are alternate, pinnately compound, 8-15" long with 5-7 leaflets. The terminal leaflet much larger and broader (usually) than the lateral leaflets. Leaflets are generally oval to oblong, entire or lightly serrated, Leaves are a medium green, shiny. Quite fragrant when crushed.

Stems (and branches) are very stout. Large terminal bud, large three lobed leaf scars, and often accessory buds that develop into flowers. The pith (inside of the young stem) is chambered. 

Here you can see the difference between a flower bud (large) and a vegetative bud (small)

Flowers are green. Arising from a second but above the vegetative bud. 

Fruit is a walnut...... a nut or some botanist consider it to be a dry drupe. The outer portion is the husk, and if you peel it off you will end up with stained hands. Eventually the husk falls off and you are left with a very hard layer. The English walnut shell is quite thin in comparison to others, but still very tough. If you like squirrels its a good tree, man they have sharp and strong teeth.

Here is the black on the left and the English on the right.

Bark is a beautiful smooth gray. Branches are massive, producing fantastic wood for cabinets and paneling. I have read reports out of the east coast where a homeowner goes on vacation and someone removes their walnut trees for the lumber.

Commercially produced walnuts are grafted onto CA black walnut rootstocks. 

Misidentification:

Hard to imagine anything that resembles this.

Location

Santa Cruz

Corner of Evergreen and Coral, you will also see a black walnut 

Elm St at the corner of Cedar St

Eriobotrya japonica - Loquat

The loquat tree is a very commonly planted tree around here. Looking like a small evergreen tree or very large bush, they grow rapidly to 20-30' with a dense rounded or dome shaped canopy often with multiple main stems. 

I think these trees are planted for the fruit because they're not really very ornamental but the fruit and leaves are interesting.

Leaves are evergreen, alternate, simple, 8-10" long, elliptical to lanceolate, dark green, leathery, sharply serrated margins, lower surface covered with yellow hairs, and often V shaped.

New growth has more white hairs than older leaves.

Stems are covered green with a dense layer of hairs. Eventually falling off (hairs) revealing a gray brown color bark. 

Flowers late fall or winter, with about 1/2" diameter white flowers in large clusters. Fragrant.

The fruits are produced in clusters of 4 to about 10 are oval or pear-shaped, 1 - 2" long, and are usually covered with short soft hairs but can be smooth. Very edible.

Being an edible fruit tree and cultivated for the fruit all over the world, you might imagine there would be lots of varieties and you would be right,  references suggest over 800. 

Misidentification:

Can't think of anything, maybe the Bronze Loquat.

Locations

Santa Cruz

312 Oceanview Ave. small but a wonderful street full of great trees.