Yerba Buena Nursery's Guide to Planting Under Oaks

Garden Guides | Garden Design Service

For Further Reference: An online book by the California Oak Foundation: Compatible Plants Under & Around Oaks

The Value of Oaks One of the most majestic, valuable and longest lasting legacies we can leave our children is the oak tree. Hundreds of species of wildlife depend on this tree for food and shelter. Our homes are enhanced by the shade and stature provided by this long-lived tree. Yet human activities such as building of homes and planting of vineyards threaten the areas where oaks remain. In addition, Sudden Oak Death is now threatening our remaining oaks, killing off portions of oak forest at an alarming rate. We need to preserve existing oaks and plant new trees for the future.

Natural Watering Patterns
Mature oak trees have typically survived in California with water gathered from winter rains and without water for the 6 month summer period. To keep your oaks alive you will want to replicate the no water pattern in summer by avoiding the use of plants under the oaks that need summer water. This particularly includes lawns! How often have we seen a mature oak fall down onto a newly planted lawn, added by a developer or homeowner, who has no knowledge of the consequences.

Root System of Established Oaks Oaks set a deep tap root and have many shallow surface feeder roots. These shallow roots extend to and beyond the canopy of the tree and should not be disturbed!. Feeder roots are typically from 12 inches to 3 feet below the soil's surface. The most critical area is within 10 feet of the base of an oak, where no planting should occur and the area must be kept dry. Organic mulch can be used in this area, provided it does not touch the crown of the tree. Between the 10 foot diameter and the dripline, minimal planting should occur. Native plants which are drought tolerant and planted in the rainy season are the best choice as they will not compete with the oak for nutrients as will other thirsty plants.

New Oaks
Recently planted oaks will need to be watered for about 3 years until they are established. After that, they should not be summer watered and should definitely not be planted in a lawn. Summer watering may not appear to affect these trees for a number of years, after which root rot and decline in health may occur.

Recommended Native Plants for Use Near Oaks

This partial list is based on plants grown at Yerba Buena Nursery and should be evaluated in terms of the amount of sun and deer present around your oaks. Plants appropriate for use near oaks will be indicated in the Nursery with an oak symbol () on the informational card.

Symbols = Sun (S), Part Sun (PS), Shade (Sh). Deer Resistant (DR), Somewhat Deer Resistant (SDR).

Shrubs

Perennials

Trees

Grasses/Sedges/Rushes

Vines

Ferns

Bulbs

California's Oak Woodland Community
The following list was compiled by the California Department of Forestry in 1996.** More than 300 species depend on oak woodlands for food and shelter. California's oak woodlands sustain higher levels of biodiversity than virtually any other terrestrial ecosystem in the State.

Species dependent on Oaks Woodlands:

Garden Guides | Garden Design Service