This is one at the SF Arboretum.
Flowers fragrant, white petals, 12 or more each 3" long somewhat oblong to lanceolate petals (way different than most of the magnolias you will see). All the male parts are yellow.
Flowers are axillary and not terminal like magnolias, If you look closely at a magnolia in bloom all the flowers are coming from a terminal bud. The stems maybe short and a lot of them but they do not flower from axial buds on stems. Flower buds are almost as pretty as the flowers. Green with a copper cast, 2-3" long.
This tree blooms for us like magnolias should, all at once rather than weakly over a month.
Leaves are alternate, simple, elliptical (oblong to lanceolate maybe) , 4-8" long, dark glossy green upper surface and lower covered with light copper colored hairs.
Another beauty in bloom in the Seacliff Area.
Misidentification:
Some magnolias perhaps. Look for the flower buds in the axils.
Location:
Aptos
535 Bayview Drive
100 Oakdale Drive
Santa Cruz
Louden Center on the Center St side of the building, about in the middle of the building.