**UPDATE!** LA River at Atwater Creek Restoration, 13 August 2016

The Dodgers play that afternoon just a few miles south of our meeting place on the river.  PLEASE ALLOW ENOUGH TIME TO GET PAST THE TRAFFIC IF YOU MUST COME IN THROUGH THE DOWNTOWN AREA. IF YOU CAN AVOID IT, DO!  After checking traffic on the radio (KNX 1070 AM does the most frequent traffic reports) or on Waze, I will probably leave the Learning Garden, driving up the 405 to the 101, to the 134 and then take streets in once I've passed the 5 - maybe even go to the 2, depending on traffic.

Your friendly instructors would like to remind our lovely students that we have another field trip this coming Saturday.  We will meet in the parking lot at the confluence of Atwater Creek with the LA River.  A lovely walk along Atwater creek until it flows into the LA River.  For Orchid and I, this is a favorite.  Our starting point is the North Atwater Park. 



View North Atwater Creek Restoration in a larger map 

Chevy Chase Drive, once it makes that final right-hand swoop, dead ends.  As that right-hand swoop begins, the park itself is on the left.  On this map, almost exactly in the blue pin there is a parking lot where we will meet at 1;30 PM.  

This is a good field trip for a camera, and as usual plenty of water and cool clothing. Wear walking shoes and we'll proceed south from the parking lot along the North Atwater Creek on down to the river proper and back again.  Not far and we will amble along without urgency.  I imagine this will be a warm day, but check your weather sources - do take proper care of yourself with the incessantly persistent sunshine!  

Some background data on the site is available online, here.
And some photos from the day it opened for a little prespective.  

Hope you will enjoy this trip and hope you're enjoying the class.

david

Low Maintenance and Low Water Trees not Native to California

David's notes for  02 August:  

Avoid 'fast-growing' not only does it mean higher maintenance, but also higher water needs.

Secondly – check non-native plants against an up to date 'invasive species' list.

Select “Species Type” = Plants

Mobile Apps on Invasive Species

What's Invasive! (free)
[iPhone][Android] The what's Invasive app displays local lists of top invasive plants and/or animals (with images and short descriptions to remind you of what they look like) that have been identified by the National Park Service or other invasive management authorities.

Calflora Observer (free)
[iPhone][Android] The Calflora Observer is a smartphone app that allows you to quickly and efficiently report wild plant occurrences. This application makes it easy for you to report the species name, date and location of over 10,000 California native and non-native plant taxa.

Invasive Plants in Southern Forests: Identification and Management (free)
[iPhone] This app provides information on accurate identification of the 56 nonnative plants and groups that are currently invading the forests of the 13 Southern States.

This will be a list of mostly small trees (usually under 30'tall) – it is not inclusive, but it is a start and these trees will mostly not do you wrong. Always, always, always MULCH under your trees and when watering strive to get water down into the 18” root zone – if in doubt, use a soil probe. No freshly planted ANYTHING is drought resistant – even trees. In the first five or more years, special attention would be best until they get established.

Plant	Notes
Apple	Check for proper fruiting in our area and use a medium to dwarfing rootstock to keep the tree from overtaking you. Apple is one of the best for a home garden because you can make the apples last longer with proper storage
Almond	Only a few will fruit in Southern California – make sure you have that covered (chill hours vary around here from 150 to 300 hours – anything with a higher value of chill hours must be avoided) - all of the fruit trees I've listed have a gorgeous floral display at some point in the year.
Chaste Tree	(Vitex agnus-castus) Produces lavender-purple flowers in early or mid-spring. The flowers give off a spicy aroma and the leaves smell faintly of sage. Shape by pruning; flowers are borne on new wood. Not extremely drought tolerant, give it some water in dry times.
Crabapple	Useful for producing pectin if you are in to homemade jams. White, pink or red flowers, self-pollinating and slow growing. Hardy without much care and a show in spring.
Crape Myrtle	(Lagerstroemia) This is a small tree of remarkable appearance when in bloom, early to mid-summer and attractive foliage come fall. The patchy attractive bark is reason enough alone to plant this tree – flowers in red, purple, white and is extremely heat resistant, not your most drought proof tree, and keep out of high winds.
Crataegus  sp.	There are species from Mexico, Europe, and China, all are called hawthorns in common parlance. Flowers from magenta to white, they are attractive hedges and can make a good fence on their own with their deadly long spines. Berries make forage for birds and other species.
Jacaranda	Jacaranda mimosifolia the common blue/purple-flowered tree around LA. Not so small, one of the large on this list,the prolific flowers are beautiful or messy depending on viewpoint. Drought resistant as a mature tree, it needs plenty of water to establish. If planted as a community street tree the effect is magical or messy, depending on viewpoint.
Jujube	Ziziphus jujuba, the Chinese Date Tree is a delightful small tree with pinnately compound leaves and small brown fruit that tastes similar to apples and can be dried. You must have two trees to get fruit,the commercial varieties are almost always Li and Lang.
Magnolia	Some species are barely more than shrubs – not to be confused with some that are quite large trees. Choose from: Star magnolia is a smaller variety of magnolia that produces beautiful, white, star-shaped flowers in early spring. The flowers are fragrant and long lasting. Grows up to 20' tall with similar spread. Cold and heat tolerant. Plant in full sun to partial shade in moist, well-drained soil. Saucer magnolia  (var. Little Star) only grows about 16' tall and 20' wide, producing large pinkish-purple flowers in early spring. Plant this magnolia in a sheltered area in full sun and moist, well-drained soil.
Maples	Acer palmatum is a slow-growing small tree with beautiful, intricate, delicate leaves make this tree a real focal point in a garden. Foliage ranges from green to deep red; some leaves are light green, edged in red. Plant in partial shade in moist, acidic, well-drained soil. Protect from harsh afternoon sun
Pawpaw	Needing more water than the other plants on this list, Asimina triloba is a 15' - 30' fruit tree native to North America, with a tropical appearance. Purple mid-spring blooms give way to green fruits that ripen to black with a pear/banana taste. Leaves turn gold in fall. Plant at least two trees for pollination. Prune off low-growing branches to give this shrubby tree a more tree-like appearance. Plant in partial shade in loose soil' full sun in CA will toast it...
Peaches	Peach trees grow 15' - 25' with dark green leaves that provide a beautiful contrast with the attractive mid-spring flowers and brilliant mid- to late summer fruit. Plant in full sun, in moist, well-drained soil. Mulch to protect the shallow roots. Prune in late winter. Most peaches are not self-fertile, depending on the variety you choose, you may need to plant more than one.
Plums	Many plums do wonderfully in our area – they are prolific and of all the fruit trees require the most effort in pruning and keeping them to size. They are not horribly drought tolerant and will need summer water – especially in their first 10 years in order to get established. They can be extremely showy with their dark purple leaves.
Quince	Quince grows 6' - 10' tall and wide, producing bright scarlet, pink, or white blossoms in spring. Some varieties bloom again in fall, but at the expense of fruitfulness. Tangled branches and sharp spines may detract from its usefulness in small spaces but make it a first-class barrier plant!. Fall-ripened fruit can be used to make jelly or jam. Prune after flowering to maintain shape.
Sweetshade	Australian relative of pittosporum, Hymenosporum flavum, besides the great dark green foliage and the sweet (honey) scent of its flowers, it is the narrowness of this tree (to 6') that makes it useful in odd spots.
Tea Tree	Tea tree (Melaleuca linarifolia) grows up to 20' tall and 12' wide. Native to Australia, the tea tree has aromatic, evergreen leaves and produces tiny white, pink, or red flowers from late winter into summer. Enjoys western coastal areas and is drought tolerant when mature. Plant in full sun. The peeling bark makes this tree much more interesting than a lot of other trees.

From Sunset magazine, with substantial edits from me:  

We need trees, especially during a drought. Trees reduce air pollution and erosion, create habitat for wildlife and other plants, and reduce the urban heat island—even hotter, drier conditions that arise in cities as a result of too much reflective pavement. Here's how to best care for your trees.

Water beyond the drip line. Most trees do not have tap roots (oaks and pines are among the few exceptions), therefore watering, fertilizing, and mulching at the base of a tree does not provide it the nourishment it needs. Roots grow 1.5 to 4 times beyond the canopy. In heavy clay soil, roots are pushed even farther horizontally and might be found 5 or more times wider than the dripline. 

Make sure moisture reaches 12 to 18 inches deep. Approximately 90% of tree roots are in the top 12 inches of soil. Use a soil probe each time you water to ensure that the moisture has reach 12–18 inches.

Remember the trees if you take out the lawn. Many established trees are planted in or near lawns. Removing a patch of grass, upon which trees might have been dependent for many years, for water due to excess lawn watering, can cause deep stress for the trees. So be sure to have a plan for continued water and fertilizing of those trees.

Look for signs of drought stress. Leaves on trees suffering from drought stress might wilt, curl, or turn yellow. On deciduous trees, look for scorching, brown edges or browning between veins. On evergreens, needles might turn yellow, red, purple, or brown. Drought stress might not cause the instantaneous death of a tree, but it weakens the overall health, paving the way for secondary insects or disease infestations in following years.

Skip the fertilizer. With a shortage of water, never fertilize which causes new growth and more need for water.

Mulch to retain moisture. Layer 4 inches of organic mulch to retain moisture between watering. Bark mulch or evergreen needles are great choices. Avoid stones as they can increase the temperature, resulting in additional loss of moisture. Refresh the mulch as needed to keep 3 to 4” of mulch over the roots.

Maintain proper pruning. Remove any broken, dead, or disease-infested branches as they can cause additional weakening to a tree's overall health. A tree with properly pruned branches will have improved structure and stability, aiding the tree in withstanding drier times.

david