Five Common Diseases of Avocado Trees

Thanks in part to the current popularity of avocados, many homeowners have begun growing their own avocado trees.

This is a great way to keep your kitchen stocked with the delicious and nutritious fruits, but the trees themselves are also quite desirable. They not only exhibit a handsome growth habit, but they also produce dense foliage, which can provide excellent shade. And because avocados grow well in Southern California, they’re likely to become even more common over time.

Diseases of Avocado Trees

Unfortunately, while avocado trees can provide substantial value to the average suburban property, they are susceptible to a variety of diseases. This includes generalist pathogens that afflict a variety of species as well as more targeted threats, which tend to harm avocado trees more than others.

We’ll talk about five of the most common diseases of avocado trees below and describe some of the most obvious symptoms they cause. This should help you spot the first signs of trouble so that you can get your trees the help they need.

1. Armillaria Root Rot

Armillaria root rot is a widespread disease that afflicts a number of tree species. In avocado trees, it generally manifests as reduced vigor and overall, generalized decline. The leaves of afflicted trees will usually look yellow, and many will fall off the tree prematurely.

2. Verticillium Wilt

Verticillium wilt is one of the easiest ailments to identify for avocado trees. Typically, the first obvious symptom involves the sudden wilting of foliage on one side of the tree. The leaves will quickly turn brown, but they won’t fall off the tree for some time. If any branches are removed from the tree, be sure to inspect them for gray-colored streaks, as this is another symptom that often suggests verticillium wilt.

3. Avocado Black Streak

Avocado black streak is a serious disease that often kills trees outright. In the early stages, the disease is often characterized by poor fruit production, blotchy markings on the leaves, and a general yellowing of the tree’s foliage. As the disease progresses, cankers often form on the trunk and branches, and new growth tends to die shortly after appearing.

4. Dothiorella Canker

Dothiorella canker is a relatively minor fungal problem that occasionally afflicts avocado trees. It usually begins with the formation of cankers on the trunk and primary branches. Over time, these cankers will eventually begin to discharge a white powder, and the bark on the trunk will begin to split and peel away from the tree. Over time, this disease often makes trees appear dead or nearly so but might recover with proper treatment.

5. Phytophthora Canker

Phytophthora canker is another serious disease that affects avocado trees. But while some trees die shortly after contracting the disease, others linger for months or years before succumbing. Phytophthora canker usually manifests as a series of lesions or cankers on the lower trunk. These dark-colored cankers often begin to leak a reddish sap-like fluid, which is often described as having a fruity odor. This disease often afflicts trees that are also infected with avocado root rot, which makes treatment particularly complex.

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Fortunately, avocado trees are relatively hardy, and they can often survive pests and disease with proper treatment. Just remember to act quickly if you suspect that your avocado trees have contracted an infection – prompt action is the best way to give your trees the best chance of survival.

If you think that your avocado trees are suffering from one of the diseases discussed above (or they are failing to thrive for any reason), give your friends at Evergreen Arborist Consultants a call. One of our ISA-certified arborists will visit your property, inspect your trees and provide actionable advice for addressing the issue.

Five Great Fruit Trees for Southern California Yards

Fruit trees are great additions to almost any yard, as they not only offer the same benefits most other trees do, they also provide you with a bounty of fruit each year. Several fruit trees also exhibit a very attractive growth habit, and a few produce beautiful, showy flowers in the spring or summer.

But to ensure your fruit tree installation is a success, you’ll need to select good species for your property. Fortunately, residents of Southern California have a number of viable options from which they can choose.

1. Persimmon

Persimmon trees (Diospyros spp.) are 20- to 40-foot-tall trees that are native to various portions of North America and Asia. They are handsome trees, with attractive bark that produce huge quantities of fleshy fruits. However, not all persimmons are created equally: Many, such as the American persimmon (Diospyros virginiana) contain bitter-tasting tannins. Accordingly, you’ll want to go with the Fuyu persimmon (Diospyros kaki‘Fuyu’), which produces very tasty fruits without many tannins at all.

2. Avocado

Avocados (Persea americana) have become very popular trees in southern California over the last decade or two, and it is easy to see why: They are very attractive, hardy trees with thick canopies, which means they not only provide delicious fruit, but privacy and shade too. You can grow avocados from seed, but you may have to wait a decade or more to get a good crop, so it is usually preferable to start with container-grown saplings. Note that different avocado varieties exhibit two different flowering patterns (termed A and B), and you’ll want some of each to achieve the best possible fruit set.

3.Meyer Lemon

The Meyer lemon tree (Citrus x meyeri) is a wonderful fruit tree for Southern California yards. Part lemon tree and part mandarin orange, Meyer lemons taste like low-acid lemons (which makes them great for deserts), and they can actually be eaten with the peel. Meyer lemons tend to exhibit a pretty bushy growth habit, and they produce sprawling root systems, so be sure that you have enough space to accommodate them before choosing them for your yard.

4. Fig Tree

Many fig trees will grow well in Southern California, but the Brown Turkey variety (Ficus carica ‘Brown Turkey’) is probably the one most ideally suited for our region. These 15- to 30-foot-tall trees grow best when planted somewhere with full sun exposure and deep, well-drained soil. Figs are deciduous trees, so they won’t provide shade in the summer. However, their growth form is quite attractive, and they still provide visual interest, even in the winter. Just be sure you like figs before planting a few of these trees, as they tend to produce two crops a year – one in late spring, and another in late summer.

5. Grapefruit

Another citrus tree that grows well in Southern California, grapefruit trees are especially well-suited for coastal areas, such as Malibu, Santa Monica and Long Beach. Several different varieties are suitable for our region, but the Marsh seedless (Citrus × paradisi ‘Marsh’) variety is one of the best choices. Grapefruit trees can be a bit tricky to grow, so you’ll need to plant them in an ideal spot to be successful – just be sure the trunk won’t be scorched in the sun, and that the soil is deep and loamy.

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If you’d like to add a few fruit trees to your yard, give your friends at Evergreen Arborist Consultants a call. We’ll assess your property, provide you with a few species recommendations and even install them for you, if you like. Proper species selection and installation is crucial for fruit tree health, so it always makes sense to solicit the help of professionals when you are starting out.

Bringing Fall Color to California: Enjoy the Changing of the Seasons

Most of the tree species that exhibit bold fall colors are native to the eastern portions of the US, with the best examples occurring in the northeast. In fact, people travel from miles around each year to check out the fall color in places like Vermont and New Hampshire.

Relatively few of the trees native to Southern California have jaw-dropping fall color, but that doesn’t mean you can’t enjoy watching the leaves change in the fall; you just need to plant a few of the right trees.

1. Maidenhair

If you like gold-colored leaves in the fall, there are few trees that can match the beauty of the maidenhair tree (Ginkgobiloba). One of the oldest tree species in the world, maidenhair trees are relicts from a time when dinosaurs walked the earth. Maidenhairs are big trees (some exceed 100 feet in height), so they aren’t appropriate for tiny lots. Be sure to select male cultivars when picking out your maidenhair trees, as the females produce copious quantities of foul-smelling seeds, which will stink up your entire yard.

2. Chinese pistache

The Chinese pistache (Pistacia chinensis) produces some of the best fall color of any tree that will grow well in Southern California. It is a moderately drought-tolerant, hardy species that is resistant to most local insects and diseases. Chinese pistaches reach about 50 feet in height, and they have a similar spread, thanks to their beautiful round canopies. Female pistache trees will produce small, purple to pink berries, which often attract birds and other wildlife. These trees will grow throughout most of our region, but because they tolerate pollution fairly well, they are one of the best choices for those living in the congested portions of Los Angeles and the surrounding area.

3. Sweetgums

If you just want eye-popping color, it is hard to go wrong with sweetgum trees (Liquidambar styraciflua). Sweetgums can produce gold, red and purple colors – sometimes in a single leaf. Sweetgums are big trees with incredibly invasive root systems, so you must be sure to select a planting location large enough to accommodate them. Naturally occurring sweetgum trees produce copious quantities of woody fruit, called gum balls, which can be quite a nuisance. Fortunately, many cultivars, such as the (Liquidambar styraciflua ‘Rotundiloba’), have been developed that do not produce fruit. However, the ‘Palo Alto’ cultivar produces better fall color and is ideally suited for the Southern California climate.

4.Japanese Maple

Maples are rightly celebrated for their impressive fall color, and the tiny Japanese maple (Acer palmatum) is no exception. Suitable for even the smallest properties, Japanese maples are famous for their slow growth rate and attractive branching structure. In our region, Japanese maples should usually be planted in partially shaded areas, so they won’t overheat in the California sunshine. Japanese maples aren’t very salt tolerant, so they are better choices for inland locations, such as Glendale and Pasadena.

5. Japanese Persimmon

The Japanese persimmon (Diospyros kaki) is a medium-sized tree that offers several different types of visual interest in the fall and winter. First, the green leaves will begin to turn yellow or orange. Shortly after this, they will begin to fall off, revealing the glorious orange fruit and the handsome, plate-like bark. Persimmons require well-drained, loamy soil, and they are moderately drought tolerant once established. In addition to the delicious fruit and attractive fall color they provide, persimmons also have very dense canopies that provide great shade.

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If you’d like some help adding a little fall color to your property, contact your friends at Evergreen Arborist Consultants. We’ll visit your property and help you figure out the best species to plant, and provide some tips for maximizing their color each year.

The Year-Round Benefits of Conifers

Residents of Malibu, Laguna Beach, Beverly Hills and the rest of the greater Los Angeles area are fortunate to have so many tree options available to them. A number of fantastic trees are native to our portion of the state, and a dizzying number of exotic species adapt well to our local climate.

But many people find the lure of beautiful flowers and glorious fall color irresistible when picking out trees for their new installation. This leads them to select broad-leafed hardwoods, such as maples, redbuds, elms, oaks and others, rather than needle-leafed conifers, such as pines, hemlocks, redwoods and firs.

This is a shame, as conifers provide a number of great benefits for homeowners and property managers. One of the most important benefits, and the one on which we will concentrate today is the fact that most conifers are evergreen (although bald cypresses and a few others do shed their leaves in the winter).

By contrast, most broad-leafed trees shed their leaves every winter. Additionally, some broad-leafed trees are facultatively deciduous, meaning that although they “want” to keep their leaves all year long, they may shed them in response to drought or other environmental stresses.

Some of the benefits evergreen conifers provide include:

Wind Screening

Because most conifers retain their leaves all year long, they make excellent choices for wind-screening projects. Shielding your property from winds can help to reduce the evaporation rate, which will help your soil retain moisture better than places exposed to constant winds. And don’t forget that dense conifers also help shield your property from anything the wind is carrying, such as dust and grit.

Shade

Those living in the northeastern United States often prefer installing deciduous hardwoods specifically because they shed their leaves in the winter. This allows them to enjoy shade in the summer and plenty of sun exposure during the winter. But here in southern California, you don’t have to maximize your sun exposure to keep Jack Frost at bay. In fact, it is more likely that you’ll want the benefits of shade in all seasons.

Wildlife Habitat

Many deciduous trees are quite important for wildlife; oaks, hickories, beech trees, for example, provide significant quantities of food for local songbirds and small mammals. Some animals even take shelter inside cavities made within these trees, or make their summer homes amid the dense and concealing canopy. However, because this canopy disappears in the summer, many birds and tree-dwelling mammals prefer to reside in conifers all year long. Some birds even preferentially nest in specific conifer species.

Privacy

Your desire for privacy probably doesn’t change with the seasons, and neither should the trees you use to provide that privacy. A nice hedge of arborvitaes, for example, will remain thick, lush and visually impenetrable all year long, while a row of maples will expose your property to anyone driving by once November rolls around.

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Of course, there are plenty of other benefits various conifer species provide. Some, such as pines, provide important food sources for your local critters, and others, like Korean firs, are simply gorgeous, and immediately become the centerpiece of any property. No matter which conifers you select for your yard, just be sure to consider the local conditions and the space you have available (some conifers grow quite large).

If you’d like some help picking out and installing some conifers for your property, reach out to your friends at Evergreen Arborist Consultants. We’ll help guide you through the process in every way, including species and site selection, installation and follow-up care. Most homeowners and property managers can complete all of these steps on their own, but it never hurts to have some help from arborists with more than 28 years of experience.

The Iconic Jacaranda Trees of Long Beach

The jacarandas of Long Beach are among the most iconic trees in southern California. In addition to growing well in the climate of the area, they are some of southern California’s most eye-popping trees – at least for a month or so. But even for all of the beauty and benefits they provide, some residents wish the jacarandas would all go away.

Jacaranda Basics

Blue jacarandas – known to botanists and arborists as Jacaranda mimosifolia – originally hail from central South America, but they’re currently cultivated in suitably warm climates all over the world. They do not tolerate freezing temperatures well, but hardy, established trees often survive temperatures as low as 20 degrees Fahrenheit.

Jacarandas occasionally reach about 60 feet in height or so, and they often develop a round or vase-shaped canopy. Because of their typical growth habit, they were often planted on both sides of a street, which creates something of a closed canopy.

Jacarandas grow best in areas with deep, fertile soils, and plenty of direct sunlight. Because they do not tolerate excessively dry soil, it is important to provide supplemental irrigation during dry spells. Additionally, you’ll want to provide this water in the appropriate manner (high quantity / low frequency) so you can encourage the development of deep root systems.

The Magical Month of May

Despite their many positive traits that led to their popularity, jacarandas are most famous for their glorious blue flowers which usually burst forth in late April or May. During this time, the purple-blue flowers dominate the landscape and create a truly amazing aesthetic that lasts for about a month or two.

The individual flowers grow to about 2 inches in length and are borne on foot-long panicles (stalk-like structures). A number of bee species are attracted to the fragrant, trumpet-shaped flowers, where they assist in pollination duties.

A Love-Hate Relationship

It is hard to argue that jacarandas in bloom are jaw-droppingly beautiful. But soon enough, the flowers will have served their purpose, and the trees will begin carpeting the ground in blue petals as the fruits begin to mature. Given the high number of flowers on jacaranda trees, this causes quite a mess.

Homeowners living under jacaranda canopies frequently complain about the shed petals, which end up everywhere. They fill up rain gutters, cover up drainage grates and find their way into homes, where they may stain light-colored carpets. Some residents are even forced to use blowers to clear away the thick layer of petals covering their property.

But this frustration eventually comes to an end, as the petals finally disappear, and the jacarandas fill their canopies with gorgeous green, feathery foliage. And this causes many to forget about the headaches they briefly cause after flowering until a year passes, and they’re faced with another mess to clean up.

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If you need help caring for your jacaranda trees, or you are considering installing some on your property, give your friends at Evergreen Arborist Consultants a call. Jacarandas grow really well in Long Beach, Beverly Hills, Santa Monica and the rest of the greater Los Angeles area. Let us help beautify your yard today!

Six Great Wildlife Trees for Southern California Properties

Thanks to urban sprawl, habitat destruction, climate change and a host of other factors, many wildlife populations are experiencing troubling population declines. But fortunately, there’s something you can do to help give your local critters a helping hand: Plant trees with a high wildlife value.

What Makes a Tree Valuable to Wildlife?

Trees support animals in a number of different ways. One of the most obvious methods they do so is by feeding squirrels, birds and insects. Some trees – oaks and cherry trees are great examples – do so by producing abundant and calorie-rich nuts, fruit and seeds, while others do so through the production of nectar, upon which birds and insects feed. And don’t forget that these birds and insects serve as food for larger predators, meaning that trees essentially support two rungs of the local food chain.

Other trees provide things like shelter or habitat to the local animals. Many owls, nuthatches and wrens take up residence in tree hollows, while woodpeckers make their own cavities to inhabit. Others simply take shelter among the tree’s leaves, particularly those trees with exceptionally dense foliage.

Additionally, trees also alter the local habitat’s temperature, humidity and wind flow patterns, which also affect the local wildlife. For example, animals seeking shelter from the mid-day sun often move into the shade provided by trees.

Six Great Wildlife Trees

The following six trees will not only make great additions to most Bel Air, Beverly Hills or Santa Monica properties, while also providing a little bit of help for the local fauna. Whenever possible, it is helpful to include species that provide different types of resources. For example, you may want to install one species that provides food and another that provides cover or shelter.

1.Willow Acacia (Acacia salicina)

Willow acacias are relatively small trees, who grow to about 40 feet in height; however, they are able to attract large numbers of birds in spite of this modest size. A drought-tolerant, sun-loving species, the willow acacia is capable of adapting to most soil conditions and will thrive in most yards.

2. Strawberry Tree (Arbutus unedo)

Strawberry trees often become an instant favorite of those who see them covered in orange to red fruit during the fall or winter. But these fruits aren’t only attractive – they’re quite appealing to an array of wildlife species, including everything from crows to foxes to raccoons.

3. California Ash (Fraxinus dipetala)

Unlike many of its cousins ranging throughout the northern and eastern parts of North America, California ashes are fairly drought tolerant, and can be grown outside of low-lying areas. Birds are not only attracted to the tree’s numerous and calorie-rich seeds, but they also benefit from the shade provided by the dense foliage.

4. Monterey Cypress (Hesperocyparis macrocarpa)

In addition to being one of the most iconic trees native to the state, the Monterey cypress is also a great wildlife tree, which attracts birds, squirrels and many other animals. In addition to being drought tolerant, Monterey cypresses can withstand the salt spray that can be a problem for other trees growing near the coast.

5. Blue Palo Verde (Parkinsonia florida)

Blue Palo Verde perform very well in most Bel Air, Beverly Hills or Santa Monica properties due their drought tolerant characteristics.  They generally reach heights around 25 feet and are another great choice for attracting birds.

6. Coast Live Oak (Quercus agrifolia)

Coast live oaks are good candidates for Southern California landscapes because they do not require a lot of water.  They are also great trees for attracting wildlife and as they mature, can provide a large canopy covering for birds.

If you would like to help feed and shelter your local wildlife, contact your friends at Evergreen Arborist Consultants a call. Whether you live in Bel Air, Beverly Hills, Santa Monica or any other part of the greater Los Angeles area, we’d be happy to help you select species with the highest possible wildlife value for your Southern California property.

The Best Palm Trees for Beverly Hills Properties

While the glitzy homes and movie stars are perhaps Beverley Hill’s biggest claim to fame, the city’s iconic palm trees aren’t far behind. Palm trees line many of the local roads and throughways, and help provide much of the city’s visual charm.

But palm trees needn’t be limited to Rodeo Drive or Hillcrest Road – you can plant your own palm trees, provided you have the space and resources necessary to care for them. However, the world is home to some 2,600 palm species, and some are better suited for the city than others are.

Many tree problems begin with poor species selection, so give the following species consideration if you are interested in adding a few palm trees to your property. If you’d like some help selecting and installing palm trees (or caring for the ones you already have), be sure to contact your friends at Evergreen Arborist Consultants.

Mexican Fan Palm

The Mexican fan palm (Washingtonia robusta) is one of the best-suited species for any location in southern California, including Beverly Hills. But you need to understand what you are getting yourself into: Mexican fan palms occasionally reach heights approaching 100 feet. Mexican fan palms are slightly less cold-hardy than their Californian counterparts, but this is rarely an important criterion for Beverly Hills homes.

California Fan Palm

California fan palms (Washingtonia filifera) are the only palm native to California, and as is usually the case, native plants are among the best choices for any property. In fact, California fan palms are often regarded as one of the hardiest palms in widespread usage. Reaching about 50 feet in height, these palms are much better choices for small locations than their larger Mexican cousins.

Mexican Blue Palm

Mexican blue palms (Brahea armata) are another great option for those living in Beverly Hills, and they provide a slightly different color to the landscape than most other palms do. Shorter and stouter than the fan palms, Mexican blue palms have thick “trunks” and reach about 60 feet in height. One of the most drought-tolerant palms suitable for the area, they are also adaptable to partially shaded areas.

Queen Palm

The queen palm (Syagrus romanzoffiana) is one of the most widespread palms in Beverly Hills, partly because they are a fast-growing species, which can quickly reach impressive size. However, queen palms need more regular maintenance than many other palms, as the fronds are not long-lived. The edible fruit produced by the tree are often eaten by birds and other wildlife.

King Palm

King palms (Archontophoenix cunninghamiana) don’t reach the heights of the Mexican fan palms, and they generally stay under 50 feet in height. King palms do not require the same level of care as queen palms and some others do, and they are very adaptable plants, that can thrive in full sun or partial shade.

Guadalupe Palm

The Guadalupe palm (Brahea edulis) is one of the smaller palms that works well in Beverly Hills properties. While they occasionally reach 45 feet or so in height, most remain much smaller than this. Hardy little plants, these palms often tolerate poor soils, as well as high winds.