Tree Care
Benefits of Keeping Trees Healthy
As our population expands and our cities grow, we are encroaching on natural areas that are essential to our environment. Trees are an easy answer to this predicament!
Many people associate trees with pollen, allergies, messy leaf clean ups and more, but their benefits greatly outweigh these perceived negative attributes. Trees:
increase property value
reduce run-off and increase groundwater recharge
cool outside temperatures
turn carbon dioxide into oxygen, and
medical studies have shown that people with a view of trees from their hospital rooms recover faster than those without.
Taking care of trees may seem like an inconvenience, or just feel like something you aren’t qualified to do, but with proper knowledge, it is quite simple to keep these essential parts of our ecosystem alive.
Tree Selection
If you are interested in planting a tree or two in your yard, it is important to know which trees grow well in the Bay Area climate. The kinds of trees you are looking for will be drought-tolerant and non-invasive. Here’s a list of some good options:
Laurus nobilis “Saratoga”
An example of a small canopy tree
Small canopy - as tall as, or slightly taller than, a basketball net: Chilopsis linearis ‘Burgandy’, Cercis canadensis, Laurus nobilis ‘Saratoga’
Medium canopy - as tall as a 3-4 story building: Acer campestre ‘Panacek’, Gingko biloba, Quercus buckleyi
Large canopy - as tall as 10 7ft tall people stacked on top of each other: Zelkova serrata, Umbellularia californica, Platanus racemosa
Most municipalities in Santa Clara County require you to obtain a permit or submit a request to plant a tree in your park strip. Depending on your city’s regulations, you may be able to choose the kind of tree you would like, depending on the space you have. If the city does not provide you with a pre-approved list to choose from, Our City Forest Community Nursery is an excellent resource if you are looking for a street tree (or any tree) and don’t know where to start. If you have been issued a permit by your city to plant a tree, bring it to the nursery, and the volunteers there can help you find the tree that is right for you. If you have questions about planting and maintaining trees, click on the name of your city to get more information.
Campbell (408) 866-2145
Cupertino (408) 777-3269
Gilroy (408) 846-0451
Los Altos (650) 947-2750
Los Altos Hills (650) 941-7222
Los Gatos (408) 399-5770
Milpitas (408) 586-2600
Monte Sereno (408) 354-7635
Morgan Hill (408) 778-6480
Mountain View (650) 903-6273
Palo Alto (650) 496-5953
San José (408) 794-1901
Santa Clara (408) 615-3080
Saratoga (408) 868-1276
Sunnyvale (408) 730-7506
Planting Instructions
Our City Forest has been planting trees in Santa Clara County for over 20 years. This graphic they developed shares the steps to a successful urban tree planting:
Tree Maintenance
Watering instructions
Correct watering is essential for your trees’ survival, and depending on the age of your trees, different amounts of water is needed.
When your tree is just planted, immediately give it 15 gallons of water, right next to the trunk. If you have a 5-gallon bucket, pour 1 bucket at a time, waiting until all of the water has been absorbed before pouring the next one. This is called “deep root watering”:
0-3 years - When a tree is this young, it needs regular heavy watering. You should water your juvenile tree with 15 gallons of water a week. This can be 5 gallons three times, or all at once. At this stage of your tree’s growth, you should continue to water it when it is raining.
3-5 years - After 3 years, your tree should be mature enough to handle less water. You can water 10-15 gallons every other week for the 3rd year, but for the 4th and 5th, watering can be much more infrequent; 3-4 deep waterings during the summer.
5+ years - After 5 years, your tree will be able to fend for itself for the most part. You may want to water it once or twice if it has been particularly hot or dry, or you start to notice a decline in your tree’s health.
For more information about watering your trees, check out Save Our Water.
Pruning guide - If you have a street tree (in the area between the street and your yard) and you live in Santa Clara County, it is possible that you either need to obtain a permit before pruning your tree, or that pruning is left up to your city’s discretion. In some cases, you need a permit to prune more than 25% of the canopy on any of your trees. Pruning requirements should be clearly stated on your city’s website.
If you are not required to obtain a permit, pruning young trees is an important step in their growth process. Healing is easier when trees are smaller, and they will have fewer structural problems as they mature. If you have a mature tree that needs to be pruned, it is safest, and sometimes required, to contact a certified arborist to do the work for you. Additionally, some trees are designated as “heritage trees” or protected trees, and have special protections applied to them. Your city’s website can also provide information about “heritage trees” or protected trees.
Some things to remember - Pruning is best done when your tree is dormant. This is usually in the winter, although you should refrain from pruning while it is raining or if it is going to rain soon. When you are pruning, try not to take off more than 30% of the canopy. Topping a tree can either kill or seriously compromise the structural integrity of the tree. You may be tempted to do this if you think your tree is getting too tall, but if tree size, and planting space available are taken into consideration when choosing a tree, height should not be a problem. If your tree is mature, and has started growing into power lines, your utility company should be able to prune the tree to correct this issue
To ensure your tree has enough resources to continue growing healthily, make the most necessary cuts first, then decide whether you can take more off the tree, or if you should wait until next year.
The Arbor Day Foundation has a handy pruning guide if you have questions.