Most trees in California need supplemental irrigation above and beyond what Mother Nature supplies naturally. Even drought-resistant species need regular watering through their first growing season due to their shallow roots. Once trees become established, it's important to water less often but more deeply to encourage deep rooting and structural balance above and below ground. Both under and overwatering can lead to unhealthy trees and even death if the situation is not corrected. Trees receiving too little or too much water exhibit similar symptoms since, in both cases, water is not available to the plant. Trees initially wilt, grow slowly, and develop yellow leaves. Over time, growth stops and leaves become brown and drop. Overwatered trees often develop lower crown and root rot from one or more disease-forming pathogens.
Knowing what type of soil you have (soil texture) is as important as knowing the water needs of your trees. Use the ‘feel test' (pictured below) to find out how much water your soil holds and how often to water. Heavier clay-based soils hold water longer and drain more slowly than sandier soils that need to be watered more often for shorter periods of time.
Trees should not be watered on the same irrigation system used for lawns and groundcovers. Soaker hoses and drip systems allow trees to be watered less often but for longer periods of time than your lawn or groundcover. Avoid applying water too close to the trunk. Instead water half-way between the trunk and the dripline of the tree and outward. If you use a garden hose, apply the water on the lowest volume possible slowly, moving the hose every few hours to each of four quadrants around the tree.
Applying a 3-4 inch layer of mulch around the tree can reduce soil evaporation. Use only non-flammable mulches in fire-prone areas within five feet from the house and non-contiguous for the first 30' away from the house. In all cases keep mulch a few inches away from tree trunks to keep the trunks dry.
Tip: Before planting a tree, make sure there is adequate drainage. Dig a hole where you want to plant it (the same depth of the pot, which is about one foot) and fill the hole with water. Let it completely drain and refill it. Measure the time it takes to drain one inch using a ruler. If it does not drain more than one inch an hour it is not a good location for your tree. Avoid adding compost or soil amendments to try to correct the problem since tree roots will likely grow in circles, staying within the confines of the amended hole rather than growing outward the confines of the amended hole rather than growing outward.
Dear Community Members and UCCE Partners Throughout San Bernardino County,
I hope this finds all of you and your families well and staying healthy. Please note that, due to COVID-19 concerns, all UCCE San Bernardino County face-to-face program activities, classes, and other events scheduled through April 30, 2020 have been postponed, canceled, or converted to zoom meetings or other distance learning formats. However, our academics, program managers, and community educators remain on the job and available to assist you via phone and email. Volunteer Master Gardeners continue to address your home horticulture inquiries through their telephone (909)387-2182 and email helplines (email@example.com).
Thank you for your understanding and your flexibility as we continue to provide research-based information in new and novel formats during this difficult time. Follow us on twitter (@MGPSanBern and @UCANRJHartin) and visit our website http://cesanbernardino.ucanr.edu/ for more updates including our Fiscal Year 2019/2020 Annual Report.
Have you ever thought about the parallel between preventive health care for people and integrated pest management (IPM) for plants? Both implement specific measures that reduce the risk of exposure to disease-causing organisms. According to experts, implementing preventive measures such as ‘physical distancing' (I prefer that term over ‘social distancing'), washing our hands thoroughly and regularly, covering our mouths when we cough, not touching our face, etc. greatly reduce our chance of contracting COVID-19.
In the plant world, IPM practices and principles that promote healthy plants greatly reduce the chance of damage from diseases and other pests. With a little extra time on your hands, implement these IPM practices for a healthier garden and landscape: match plants to their preferred climates and microclimates; select disease resistant plant varieties; provide well drained, healthy soil amended with compost and other organic products when appropriate; apply the right amount of water and nutrients at the right time, etc.
A ‘silver lining' of adopting these practices is that the need for pesticides is greatly reduced which keep our waterways clean, and preserves (and even enhances) populations of beneficial microbes, pollinators and wildlife.
Here are some other ‘silver linings' that I want to share with you in hopes they will provide some inspiration for you to ‘landscape greener' during what I hope is some extra downtime.
• Fewer vehicles on the roads has temporarily improved our air quality. With some extra time on our hands, we can all contribute to a more permanent solution by planting a tree or two! Trees store carbon dioxide that reduces pollution, cool urban heat islands, provide shade, reduce interior energy use and costs, provide habitat, connect us with nature, and beautify our neighborhoods.
• Stay in touch with family, friends, and even co-workers at a distance via 'walking chats' that improve our physical health and even reduce stress by increasing the “feel good” hormone serotonin. Keep it up and it just might earn you a place in the “100 mile a month walking club.”
• With more time to catch up on reading, consider downloading free UC ANR publications such as: ‘Sustainable Landscaping in California' anrcatalog.ucanr.edu/pdf/8504.pdf that provides tips on water savings, use of soil amendments and mulch, reducing pesticide use, and more.
• More time on our hands provides an opportunity to stock our ‘little free library' with vegetable and flower seeds for our neighbors. Don't have an official ‘library'? Build your own ‘seed sharing box!' Or, donate seeds and plants to a local food bank or other non-profit.
I hope that you and your loved ones stay well and healthy! We will get through this together.
Congratulations to our 52 San Bernardino County University of California Cooperative Extension (UCCE) Master Gardener graduates from all corners of the county! Please help Master Gardener Coordinator Maggie O'Neill, previously certified Master Gardeners and myself welcome these new volunteers who completed their 18-week training course and graduated on February 18, 2020 in Loma Linda.
What does it take to become a UCCE Master Gardener? Dedication, passion, a strong desire to help local residents and communities garden more sustainably. Each graduate completed an 18-week training session with weekly classes on sustainable landscaping, growing vegetables and fruits in home, school, and community gardens, pest management, and building healthy communities. Course requirements included passing a midterm and final exam and presenting a class (project to peers in a group setting. Most importantly of all, graduates each made a pledge to volunteer at least 50 hours of their own time over a one year period to help residents of San Bernardino County garden smarter.
Thanks to the continued dedication of over 150 previously trained Master Gardeners, San Bernardino County now has the talents of over 200 knowledgeable Master Gardener volunteer who you will very likely meet at local events and activities from Chino Hills to Yucaipa as well as in desert and mountain communities alone or in partnership with over 75 collaborating agencies, cities, schools, and county departments.
Since a picture can paint 1,000 words, we hope you enjoy living vicariously through a few graduation photos! Fiends and family members alike enjoyed an evening of celebration in honor of their Superstars who they are rightfully very proud of!
Thank you to each and every one of our new graduates! You helped UC Cooperative Extension in San Bernardino County reach over 30,000 county residents each year garden more sustainably through public workshops and classes, information booths,Farmers Markets, telephone and email helplines, develop school and community gardens, and many other activities throughout San Bernardino County communities.
Are you interested in becoming a UCCE Master Gardener? The next 18-week class will be held at the Chino Basin Water Conservation District in Montclair on Saturday mornings starting in late Spring 2020. Please contact Master Gardener Coordinator Maggie O'Neill at firstname.lastname@example.org for a link to the online application. Residents of San Bernardino County over the age of 18 are eligible to apply. No formal college degree is required. However, Department of Justice background clearance is required by the University of California prior to participating in any volunteer activities.
The Goldspotted Oak Borer (GSOB) (Agrilus auroguttatus) continues to kill native oaks in several areas of Southern California. Susceptible oaks include coast live oak (Quercus agrifolia), canyon live oak (Q. chrysolepis), and California black oak (Q. kelloggii). In many cases, GSOB has damaged or killed mature oaks valued for their beauty, wildlife habitat, and shade. Areas with large numbers of native oaks are particularly at risk. Unfortunately, oaks that are injured over several years from multiple generations of the GSOB often die.
Although GSOB was first identified in San Diego County in 2004 it wasn't until 2008 that oak deaths were linked directly to GSOB. By 2010, GSOB killed over 20,000 oak trees growing in forests, parks, and urban areas in San Diego County. Later infestations occurred in Idlyllwild (2012), Orange County (2014), and Los Angeles County (2015). The three most recent outbreaks have all occurred in San Bernardino County. The first occurred in Oak Glen in 2018 followed by infestations in California black oaks in the Sugarloaf area of Big Bear in August 2019 and in Wrightwood in early November 2019.
The GSOB is native to southeastern Arizona where it is not destructive to otherwise healthy native oaks. This may be due to natural enemies and/or resistant oak species that have co-evolved with GSOB. Damage. Damage occurs from larval feeding on the vascular (water and nutrient conducting tissues) system inside trunks and branches. Infested trees have black stained bark and may ooze sap underneath red bark blisters. Adult beetles leave a distinctive D-shaped exit hole.
Damage from GSOB adults feeding on leaves is not a major concern. Insect Identification. GSOB larvae are about 0.8 inches long, white and legless with two pincher-like spines on the end of their abdomen. Adult GSOB are smaller (about 0.4 inch long) and are mostly black with six gold spots on their forewings. Soft-bodied pupae resemble adults in size and shape and are found in the outer bark from late spring to early summer.
Prevention is important since there are no known control methods once trees become infested with GSOB. Keeping infected firewood onsite is the most effective way to stop its spread. Wood should never be moved offsite since this is the major method by which GSOB is spread. No known natural enemies have been identified and insecticides are not generally effective. Monitoring susceptible trees species and identifying and reporting new infestations early are both important.
If you believe there is an infested oak on your property please submit photos of the entire tree, a close up of a leaf (to confirm the species), and a close up of the surface of the bark on the main trunk. If possible, include a photo of an unsharpened #2 pencil tip next to any visible exit holes since are both around .15 inches wide. https://ucanr.edu/sites/gsobinfo/Help_Monitor/Report_Goldspotted_Oak_Borer_Symptoms/ A team of scientists from UC, California Department of Forestry and Fire Protection, CALFIRE and the U.S. Forest Service and other agencies are working collaboratively to reduce the devastation from this insect and identify effective biological control agents.
I love research results that can be applied to everyday life and wanted to pass along a couple of tidbits. Did you know that playing in the dirt (e.g. what adults call 'gardening') and getting your hands dirty can boost your serotonin levels, producing a feeling of calmness and increasing your happiness? This is because many soils contain a bacteria called Mycobacterium vaccae which triggers this 'feel good' response. But the benefits don't stop there. Serotonin can also boost one's immune system which is a welcome outcome during flu season.
Another very interesting finding is that harvesting the fruits of your gardening labor, whether it be tomatoes or squash or even Brussels sprouts, can increase dopamine levels in your brain. This chemical rush results in mild euphoria. Researchers have even documented that just plucking an eggplant off a grocer's shelf can mimic this response. Evolutionary biologists are not at all surprised, attributing the more 'modern day' response to the onslaught of rural populations to cities and urban areas where fewer people actually grow their own food.
Have you ever heard of the term 'biophilia'? It was coined by Dr. Edwin O. Wilson, an entomologist studying the social behavior of ants and suggests that there is an instinctive bond between human beings and other living systems. I look forward to the day when there is adequate evidence that I can blog that biophilia is a fact rather than a theory! I do believe living things prosper together.
And, it's no wonder that school gardens are becoming so popular. K-12 students who engage in gardening are found to have greater self esteem, lower rates of depression and anxiety, improved social skills, a greater sense of cohesiveness and belonging, a lower body mass index and healthier diets. In many cases students engaged in gardening activities that are directly connected to mastering core subject matter even earn higher grades and perform better on standardized tests.
What does all of this have to do with our University of California Cooperative Extension programs in San Bernardino County? Our Master Gardeners, Master Food Preservers, Expanded Food and Nutrition (EFNEP) educators and 4-H members have banded together across professional disciplines to promote school gardens and healthy diets in several locations. As they say, a picture paints 1,000 words. You decide! I bet you can't help but smile (which is also good for your health) at the success of these events for both the students and the staff!