Heads up for Tree Cities USA

 When they were planting the Urban Forest, did they ever imagine a really severe drought?
11-12-14
Ukiah Daily Journal
Heads up for Tree Cities USA
Trees may need extra care, officials say
Preparations for winter encouraged in case rain is scarce
http://www.ukiahdailyjournal.com/news/ci_26926506/trees-may-need-extra-c...

California's drought is having a visible impact on lawns throughout the state as homeowners reduce their outdoor watering. Lawns can be brought back to life relatively quickly, but once a tree dies, its loss is irreversible, according to a news release from the California Department of Water Resources.
As the amount of sunlight falling on trees is reduced with the change in seasons, trees go into dormancy and require less water than during the hot summer months. But in exceptionally dry conditions, a tree may not have enough stored moisture to survive until drought conditions improve.
Tree advocates and water officials are urging homeowners to educate themselves on effective tree care to ensure their trees' survival in the months ahead – especially if California's extended dry period continues this winter.
Representatives of the Sacramento Tree Foundation, California Center for Urban Horticulture at the University of California Davis, UC Cooperative Extension and the California Department of Water Resources said a return of normal rainfall this winter might be enough to sustain trees without special care and watering.
However, with no way to know how long the current drought will continue, the advocates said knowing when and where to water a tree can be the difference between its life and death.
"We are seeing locations in California where trees are dying because they haven't been watered adequately," said CCUH Director Dave Fujino. "While homeowners are trying to save water by letting lawns die, they need to continue watering their nearby trees."
Chuck Ingels, UC Cooperative Extension horticulture adviser, urged homeowners to follow these steps:
• Dig into the soil 6 to 8 inches at a tree's drip line – the area immediately below the widest part of the leaf canopy; if the soil feels dry and crumbly, it needs water
• Apply water slowly and uniformly using low-volume application equipment, such as a soaker hose that circles the tree at the drip line. Allow water to saturate the soil to a depth of 8 to 12 inches.
• Allow the soil to dry between watering. For most mature trees, one or two deep waterings per month is adequate. Fewer waterings – and perhaps none – are needed during the cooler and potentially wet winter months.
• Add mulch (leaves or wood chips) between the trunk and drip line to retain the soil's moisture.
• Reduce competition for water by removing weeds and grass within 4 feet of a tree's trunk.
If a homeowner has allowed a lawn to dry up during the drought, trees growing in that lawn may not be getting enough water and may need more to help them transition into winter dormancy.
Anne Fenkner, of the Sacramento Tree Foundation, said trees have varying water needs depending on their species, age, size, slope of the ground beneath them and other factors. Homeowners can nurture their trees and improve their health by understanding tree care principles:
• Older established trees may be starved for water as well as younger trees. The low rainfall last winter did not replenish the soil moisture adequately and they may need a moisture boost before winter.
• Avoid fertilizing trees now; it will stimulate new growth at the wrong time of year.
• When planting new trees, choose species wisely. Depending on how long the drought will last, consider selecting drought-resistant varieties and delaying planting until drought conditions improve. If the drought worsens in 2015, investments in new trees may be lost.
• Improve the quality of the soil in which the trees grow. Aerate lawns so the roots of mature trees have good access to water and oxygen.