Landscaping Guide 2.1

Town of Los Altos Hills Landscaping Guide 2.1 Environmental Design and Protection Committee 1 TABLE OF CONTENTS OVERVIEW 3 IMPORTANCE OF LANDSCAPING GOALS 3 DESIGN CONSIDERATIONS 4 WILDFIRE PROTECTIONS 5 LIVING WITH CALIFORNIA OAKS 6 RIPARIAN HABITAT 9 LIVING IN THE HILLS 10 LANDSCAPE MAINTENANCE 14 HERITAGE TREES 15 GARDENS DISPLAYING NATIVE PLANTS 15 HELPFUL REFERENCE BOOKS 15 ONLINE RESOURCES 16 TABLE 1: NATIVE PLANTS 17 TABLE 2: RECOMMENDED PLANTS 20 TABLE 3: INVASIVE PLANTS 20 TABLE 4: FLAMMABLE PLANTS 21 TABLE 5: POISONOUS PLANTS 21 2 OVERVIEW OF LANDSCAPING RECOMMENDATIONS Minimize the visual impact of housing structures with plantings which blend with the natural environment. Use native, drought-tolerant plants. Reduce fire danger by creating a defensible space and managing vegetation. Avoid planting trees which will grow to block neighbors' views, interfere with utility lines, become less effective in screening, or create a wildfire hazard. Minimize or eliminate lawn area; do not use artificial turf. Choose plants appropriate to the topography and adapted to our Sunset Climate Zone 16. Protect native oak trees in construction and landscaping; hand-dig trenches within the drip line (canopy) of native oaks. Do not irrigate or place cobblestones under oaks. Choose plants that are compatible with oaks when planting within an oak canopy. Preserve riparian habitat and vegetation, e.g., willows. Control erosion by minimizing hardscape and using plants which can stabilize steep slopes. Do not use invasive plants; avoid poisonous ones. Consider using deer-resistant plants, or create local deer fencing. Fences should be minimized to allow the free movement of wildlife. Use wildlife- friendly fencing in wildlife movement corridors. Maintain plantings by pruning and trimming where necessary to keep them healthy, removing dead material to minimize fire hazard. Control weeds, especially in disturbed areas, when they first appear and before flowering and seeding, e.g., stinkwort and Italian Thistle. IMPORTANCE OF LANDSCAPING GOALS Many factors go into designing a landscape for a residence in a community like ours. The Town of Los Altos Hills remains one of the open country areas left in the congested, expanding cities of the Bay Area. A great number of our homes border on the natural, undeveloped areas that provide a visual backdrop for much of the San Francisco Peninsula. Our goal in landscaping is to minimize the visual impact of the housing structures with plantings that blend with the natural beauty of our native surroundings. 3 DESIGN CONSIDERATIONS At the time of new construction, owners are required to submit to the Town a plan for managing erosion on slopes and for mitigating the impact or view of new structures from off-site. The purpose is to keep the Town looking rural, to preserve the soil and to retain the original contours as much as possible. Future plantings and changes should continue with the same goals. The General Plan calls for landscaping to create maximum compatibility of development with the natural environment. As a general guideline, the Town recommends informal plantings. To achieve this, plant in random or staggered groups of a variety of species rather than formal rows of hedges. Frequently plantings are used to conceal the view of a structure, provide privacy, manage erosion or mitigate wind or noise. Trees are often the first thought but remember trees grow tall and wide. The bottom branches die out and what was meant to be hidden will become visible again. Additionally, your tree may now block your neighbor’s view or sunlight or interfere with utility lines, while it no longer serves your original purpose. Shrubs may be a better answer. Most evergreen (non-deciduous) shrubs will top out below 20 feet and continue for years to give privacy clear to the soil level. When selecting trees that bear fruit, remember that the fruit must be harvested to prevent it collecting on the ground and attracting rodents. Trees and large shrubs should not be planted next to property lines or pathways where they will grow to infringe on them. Pathways should be kept free from plantings within 3'-5'. 4 Other design considerations are the water needs of the plants you select. Grouping plants according to their water needs will improve their success. Water saving is be a big item of consideration as the State’s population increases in the future, and climate change can exacerbate droughts. Water supplies are finite and we will all be required to minimize our use of landscape water. See the Water Efficient Landscape Ordinance for details of calculating your irrigation budget. Lawns are the biggest users of water and fertilizer, so try to have only the amount of lawn you really need for your family use and use drought tolerant plants elsewhere. Consider many of the low water lawn alternatives. Some of the easiest drought tolerant plants are the ones that evolved here naturally. These are our own native plants, many of which are available at local nurseries. (See Table 1: Native Plants) Vineyards and orchards can require large amounts water and chemicals, and they displace native habitat. Also, when designing your landscape, consider the site. Is it an exposed hill or a shady valley? What is the soil type? Use plants that are adapted to these conditions, and thus require less use of chemicals and maintenance in the garden. Any plant that requires frequent pruning may be the wrong plant in the wrong place. We live in a Mediterranean climate in Los Altos Hills, characterized by warm, dry summers and wet, cool winters. The best time to plant is in the fall at the time the rains are beginning. The soil is still warm, thereby allowing the roots to establish. The air is cooler so there won’t be much top growth and the rains will do most of the watering for you. However, if the rains are inconsistent, supplemental water will be needed. Fall planting will give your plants a head start on early spring growth. If you miss the fall planting season, winter and spring are second best and summer least favorable. The Sunset Western Garden Book is a good source of information for appropriate plantings for our climate. According to Sunset, our zone is 16. All plantings should be chosen for their adaptability to this zone. WILDFIRE PROTECTION Since wildfire is becoming increasingly common and destructive in California, especially in wildland/urban interface zones such as that occupied by our town, this must be taken into account in designing landscaping. Sometimes this conflicts with creating adequate screening for new homes, and a balance must be found. To prevent the likelihood of wildfires damaging your home, the Fire Safe Council recommends creating a defensible space around structures. Remove dead plants and clean out dead material from your living plants in such a way that it does not accelerate erosion and flood potential. Trees should be kept a distance from any structure at least as wide as the mature crown. Additionally, large shrubbery under trees can create a fire ladder allowing the flames to ignite the tree foliage. Pines, junipers, cypress and eucalyptus trees contain flammable oils and burn especially fast; they should not be planted near the house. (The Town requires several species of eucalyptus trees to be removed when property is developed.) Trees should not be planted under power lines; follow PG&E guidelines in their "Right Tree Right Place" web page. Defensible space is organized by zones based on proximity to a structure: 5 Zone 0 (0-5' from house): this zone should have no flammable material, only hardscape, gravel, etc. Tree branches should not overhang the house. Zone 1 (5-30' from house): Use few trees and shrubs, widely spaced, with no ladder fuels. Wood chips are the most fire-resistant mulch. No highly flammable plants, e.g., juniper and pine, should be planted. Plants requiring water should be irrigated during the summer and droughts to keep them green and healthy. Zone 2 (30'-100' from house): Trees and shrubs, or groups of them, should be adequately spaced, depending on the slope, with no ladder fuels. Hardening your home against wildfire is also very important; residents can have a Hazardous Ignition Zone (HIZ) survey completed by the Santa Clara County FireSafe Council, to assist with questions and offer suggestions. See the Fire Safe Council's "Homeowners Checklist" and "Fire Safety Information for Residents" and "Right Tree Right Place" listed in the Online Resources section. LIVING WITH CALIFORNIA OAKS 6 In Los Altos Hills, we are fortunate to have many native oaks. Oaks give us shade and shelter, increase our property values, create carefree beautiful landscapes and provide food for native wildlife. Oaks require very low water and are low maintenance trees. Unfortunately, inappropriate landscaping, such as lawns or high water plantings, and construction practices can seriously damage these trees. Often the damage is not evident until years later. As homeowners living with these beautiful trees we are in the best position to protect and enhance our native oak resources. Careful planning and design can provide benefits for both people and oaks and the many species that depend on them. Valley oaks and coastal live oaks are recommended. Oak Moths are native insects which live in our oaks; they are an integral part of the ecosystem, providing food for birds and bats; oaks should not be sprayed with insecticides to kill them or their caterpillars. Note that a permit is required from the Town to remove any oak larger than 12 inches in diameter. Also see the Town's Tree Ordinance. OAK ROOTS Oak roots stabilize our hillsides and help reduce storm water runoff.

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