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This tree to the left of the entrance to the Palo Alto Junior Museum has a unique leaf shape and it turns a gorgeous golden yellow in the fall. Because the leaves fall nearly all at once, they create a carpet of color beneath the tree. Ginkgos have been around for a very long time. Some fossilized gingko leaves have been dated to 270 million years ago – the time when dinosaurs still roamed the earth, hence it is nicknamed “Dinosaur Tree”.
To the left of the Ginkgo is a huge example of a tree that is rare in the Bay Area. Pecans are more common in the south-central U.S., where nuts drop from the tree in the fall. The nuts don’t ripen properly here because the climate is too cool. A long stem with 11-17 opposite leaflets makes up a large single leaf called a compound leaf.
Growing in a parking lot divider, this Australian native is a nice choice for an evergreen tree reaching less than 20’. It is a slow-growing relative of the eucalyptus and can take the form of a small tree, a tall screen, or a shrubby bush. It has peeling bark, clusters of small yellow flowers in late spring, and ¼” seedpods that resemble eucalyptus seedpods.
This tree at the southwest corner behind the Girl Scout House gets its name because it grows naturally primarily along the Pacific coast of California. Locally, it was probably the most common tree in the non-creek areas of Palo Alto when the Ohlone Indians lived here. They relied on the acorns of oak trees as a major source of food. The leaves of the Coast Live Oak are dark green, have sharp points around the edges, and stay on the tree year round. It is one of two types of oak trees that are protected in Palo Alto; the other is the Valley Oak, Quercus lobata. Both of these trees are adapted to very little water in the summer and should not be irrigated during dry months.
Because they don’t have any wood and they are members of the grass family, some people don’t consider palms trees at all! Tree or not, Canary Island Date Palms can grow to 60’. The trunk is patterned with the bases of old leafstalks. The graceful, arching fronds form a crown that can be 50’ wide.
Redwoods of many ages are along this path; the oldest is probably the one with the huge base nearest the fireplace of the Girl Scout House. In the coastal mountains they capture water out of fog; water drops then fall to the ground and provide moisture for the roots. Our city is named for El Palo Alto (Spanish for “the tall tree”), a 1,000-year-old Coast Redwood near El Camino Real and San Francisquito Creek.
These beautiful, graceful trees surrounding the picnic area at the back of the Girl Scout House can be evergreen or deciduous, depending on temperatures. They grow rapidly to 40–60’ with an equal or greater spread. Chinese Elms vary in shape, but usually appear spreading with long weeping branches that reach down to the ground if not pruned. Although these fast growing trees are well-adapted to our climate and were extensively planted in Palo Alto as street trees, the City no longer plants them because of the high cost of regular pruning and maintenance.
Proceed northwest along the path to three Sugar Maple street trees on Hopkins Avenue. The sap of the Sugar Maple is used to make maple syrup in native eastern North America. This species can reach 60’. Its wood is used for furniture, basketball court floors, and bowling alley lanes, among other things. A maple leaf adorns the Canadian flag.
The street tree next to the Sugar Maples is a Valley Oak. Valley Oaks are native to this area. Like the Coast Live Oak, it is a protected tree in Palo Alto and a permit from the City is required for major pruning or removal. The leaves of Valley Oaks have rounded edges and drop to the ground in the fall. The botanist’ term for trees that are leafless in winter is deciduous. Trees that have leaves all winter, like the Coast Live Oak, are called evergreen.
Two trees down from the Valley Oak, this tree shows the very spreading and symmetric form that the Chinese Pistache is known for. It has a compound leaf like the Pecan. Beautiful in the fall, the foliage becomes scarlet, orange, and sometimes yellow. These highly adaptable trees can tolerate lawn water or dry soil. They can grow to 30’ with a 30’ width and are a reliable street or lawn tree.
The next three street trees are London Plane Trees, a member of the sycamore family. London Planes are commonly planted as street trees all over the U.S. because they tolerates many soil types and stands up beautifully to the harsh urban environment. They tolerate drought quite well and may reach 80’ by 40’ wide.
Continue walking along Hopkins Avenue to a small round-headed tree next to the big pine. This evergreen is often a large shrub, but can be trained as a single-stemmed tree 15–20’ tall, such as this one and another at the corner of the Girl Scout House. It is one of the best hollies for warmer regions, including our area. With its 5” by 3” leathery leaves, it can make a good screen.
This large pine has an open, irregular crown of many short branches reaching up. The light green needles are in bundles of two and 2½–4” long (you can always tell a pine because the needles are in bundles). Native to the Mediterranean region, this pine is not a common landscape tree in this area.
Located in front of the Girl Scout House on the right side in a planting bed surrounded by pavement and growing next to the very common Southern Magnolia is an unusual tree for this area. It has a compound leaf with 5–7 leaflets arranged in a fan. Although a small old label on the tree says it is a Red Horsechestnut, it is actually a Common Horsechestnut. Common Horsechestnuts are native to Europe, but closely related to our local native, the California Buckeye (Aesculus californica). When it blooms, its white flowers with red at the base are striking. Unlike true chestnuts, this tree’s nuts are not edible.
To the right of the entrance to the Junior Museum is a tree that resembles the Coast Redwood, but has softer leaves, is lighter green, and loses its leaves in the winter. This tree is an ancient tree – it was known to scientists only by its fossil record and was thought to be extinct. It was “rediscovered” in China in 1941 and the seedlings have been sent around the world ever since. This tree is approximately 60 years old.
The three largest trees next to the Dawn Redwood are Atlas Cedars. This tree is native to the Atlas Mountains of Algeria and Morocco and may grow to 60’. It needs a large area for full development and should not be crowded. Its wood is excellent for carpentry and has a strong scent that repels insects.
Across the driveway from the Atlas Cedars are one large and two newly-planted Port Orford Cedars. The common name for this tree comes from a town in Oregon near one of the only two areas where it grows naturally. The other area is on the Northern California coast. The tree was “discovered” by Scottish botanist William Murray in the 1850s.
This planting area has several Red Horsechestnuts which you can recognize easily because each leaf is composed of 5 leaflets arranged in a fan. When in bloom in April, this tree has hundreds of soft pink to red flowers on plumes that point up. In summer, large seed capsules, the “horsechestnuts,” form. This species can grow to 40’.
Similar to the Atlas Cedars, these three Deodar Cedars have longer, softer needles and branches that droop. This conifer is native to the Himalaya Mountains. It is a fast-growing tree that can reach 80’. The cones on the tree always point up and sit on top of the graceful branches.
Cross the driveway to find an extraordinary specimen. This large leafy Red Oak has enormous reaching branches and beckons to be climbed. This tree is native to eastern North America, but it is planted widely in this area because it thrives in our climate. Its acorns are about an inch long, and the cup encloses only a quarter of the nut. The leaves turn a lovely red in the fall, and that is why it is called Red Oak.
These two somewhat leaning trees look more like the Port Orford Cedar than the Atlas or Deodar Cedars. The name Cedar is used for trees of several families. This Cedar and the Port Orford Cedar are closely related to the cypress family, while the Atlas and Deodar Cedars are closely related to the pine family. Incense Cedars are native to California and have thick bark that protects them from forest fires. The Incense part of the common name comes from the smell of the wood, which is used to make pencils.
Five of the street trees between this parking lot entrance and the entrance to the Jr. Museum are Southern Magnolias. This tree was a favorite back in the 1920s and 1930s when many were planted along the streets of Palo Alto. It has large, white, beautiful blossoms in the summer that are very fragrant.
At first glance, this tree appears to be a Coast Live Oak, but in fact, it is a Cork Oak. The bark of Cork Oak is used to make wine bottle corks in Spain and Portugal and always has a rougher appearance than that of Coast Live Oak. Many of the oldest Cork Oaks in Palo Alto are showing signs of distress, such as this one, which has lost much of its original canopy.
Easily recognized because of its unique twisting shape, this tree against the side wall of the Jr. Museum is mostly seen as a residential landscape bush. Many were planted in the 1960s when they were a popular landscape plant and, over time, have grown to tree size.
A permit is needed to remove or prune these trees.
Check the City of Palo Alto Tree Regulations.
These trees are best adapted to our climate and water availability.
These trees require frequent summer irrigation and will suffer from the drought cycle in our area.
Do not plant unless you are aware of a water source such as high water table or creek proximity.
These trees are either invasive, do not perform well or create infrastructure or other problems.