Save Our Water and Our Trees

Your trees provide an immense range of health, energy, environmental, and economic benefits:

• Trees improve air and water quality
• Trees provide shade to the landscape and reduce water needs
• Trees help keep your home cooler
• Trees slow stormwater runoff and help recharge groundwater
• Trees reduce soil erosion
• Trees add value – sometimes thousands of dollars’ worth – to your home & neighborhood

Trees take a long time to grow. Without helping our trees through the drought, we risk losing their benefits. While the drought may not last long, it can seriously damage or kill trees, and these benefits will take 10, 20, or even 50+ years to get back. Taking care of your trees during the drought ensures that we preserve and protect these life-giving benefits for ourselves, our families, our homes, and our communities.

Click on the videos below to learn how to care for your mature and young trees.

These videos are available in English and Spanish.

The amount of water your tree needs depends on your soil and tree type. You can check the soil moisture to see if it’s time to water. The easiest way to check soil moisture is to take a long (8”+) screwdriver and poke it into the soil. It will pass easily into moist soil, but be difficult to push into dry soil. If you can’t poke it in at least 6”, it’s time to water. This technique works best in clay and loam soils

Dead or dying trees can be dangerous and pose great risks to your property and your loved ones. Removal of dead or dying trees can cost thousands of dollars. Replacing trees takes more money, time, and water than keeping established ones alive.

Some drought-stressed trees, once too dried out, are unable to absorb water once the rains return or you finally begin watering them. Drought stress affects the long-term health and vigor of trees. Your tree may look fine this summer, but die next summer if not watered now. Grass can grow back in just a few weeks, but it can take decades for a tree to grow to full size.

Keeping trees alive helps keep your home cooler, meaning less energy and resources spent on cooling systems and decreased water use in other areas. Deep watering of trees also helps replenish groundwater.

Drought-tolerant trees, such as California oaks, need much less water than most others. Drought-tolerant trees may only need one or two deep waterings over the summer. Trees that have never received regular irrigation may be harmed by adding extra water in the summer. Contact a certified arborist if you have questions about the health of your mature tree.

Your lawn sits on the surface of the ground and has shallow roots. It needs watering a few times a week, usually with a sprinkler system. Trees need to be watered less frequently, but with deeper soaking because their roots grow deep in the earth. Lawn irrigation does not water trees effectively. It generally reaches only the first few inches of soil, encouraging weak surface roots to grow.

• Check back often at http://SaveOurWater.com/save-our-water-and-our-trees/ for new information on how to care for trees.

• To learn about programs in your neighborhood, you can check with:
  • Your local urban forest nonprofit. To locate an urban forest group near you, visit https://californiareleaf.org/network/map/
  • Your local UC Cooperative Extension. Visit http://ucanr.edu/County_Offices

Wood chip mulch is one of the best ways to save water and keep your trees healthy. A thick layer of mulch will keep moisture in the soil longer and protect the roots from summer heat, so you use less water and your trees stay happy. Mulching is great, because it:

• Reduces the amount of water needed in your yard by 10 – 25%
• Decomposes and releases nutrients into the soil
• Reduces soil compaction so roots can breathe
• Maintains soil temperature and protects roots from cold and heat
• Discourages grass & weeds – which compete for nutrients – from growing near the tree trunk

Spread mulch in a 4- 6 inch layer around your tree – your tree would love the mulch to be as wide as the canopy of the tree. You will need to either remove the lawn underneath the mulch or “sheet mulch” with cardboard or newspaper to prevent the grass from growing up through the mulch. Keep mulch 2 – 3 inches away from the tree trunk to prevent rot around the base of the tree.

You can help take care of neighborhood trees the same way as you take care of your own! Get a group together and teach others proper watering techniques, then assign a rotation and let everyone take part in caring for the neighborhood trees together.

Recent weather trends indicate hotter temperatures in general and the likelihood of more extreme weather events – such as potential flooding. We need to take good care of our trees in hot weather with regular deep watering so they can withstand harsh weather.