Taking our ecosystem for granted is no longer the norm, and thinking people the world over spend part of every day making choices that can help the planet. While there are no easy solutions to the damage human kind has done to nature, small decisions - like what kind of tree to plant in the garden - can make a difference in creating landscapes that enhance local ecosystems.

If your site and climate allow it, consider planting an oak tree. Many experts suggest that it is the best tree to plant to bolster the ecosystem, in addition to being tough, long-lived, and beautiful. Why are oaks important? Read on for more information.

Why Are Oak Trees Important?

Most are familiar with the old saying that from tiny acorns, mighty oaks will grow. But oak trees are more than large and majestic. Native American oaks have played and will continue to play an essential and central role in the survival of native ecosystems.

The oak tree genus (Quercus) goes a long way toward supporting native birds as well as the insects they use for food, and other native wildlife. Thousands of wildlife species rely on oaks for home or nurture. In addition, oaks are important in our fight against climate change.

Oak Trees and the Planet

What do oak trees accomplish that aids our struggles with climate change? Most people are aware that the emission of carbon dioxide - generally from burning fossil fuels - is one of the culprits responsible for global warming. Trees are known to capture carbon, thus lightening the load.

Why should you plant oak trees? Native oak species capture more carbon than any other genus of tree, removing this carbon from the air. They also prevent flooding and drought by holding rainwater. Backyard oak trees will hold more water than most other plants.

Feeding the Wildlife

The fruit of oak trees are called acorns, and these small, energy rich seeds feed many different types of wildlife. In fact, experts say that acorns are the number one wildlife food in the continent’s deciduous forest. Acorns are packed with energy, they store easily and for a long period of time, and serve as a core winter food for wildlife populations.

Which wildlife species eat acorns? It is easier to draft a list of those that don’t. Dozens of species from wild birds to deer and bear consume acorns directly. They are also consumed by gray squirrels, fox squirrels, flying squirrels, mice, voles, rabbits, raccoons, opossums, gray foxes, wild turkey, red foxes, jays, and wild hogs. Other species may not consume acorns but profit from them - like bobcats, whose diet includes smaller mammals that survive by eating acorns.

Even more species rely on oak leaves and stems, from invertebrate moth larvae to frogs and salamanders. The young foliage and shoots offer browse for rabbits and deer. It may not be the most desirable browse to these species, but they can turn to it in times of food shortages. And insect-eaters like birds and spiders use oak trees as feeding sites, thanks to the profusion of insects on the branches of some species.

Housing Wildlife

But food is only one aspect of the benefits animals get from oak trees. A second important resource is habitat in the form shelter, or cover. Many oaks produce lush leaves, and this dense foliage is perfect for concealing bird nests, insect nests, and squirrel nests. Nest-building wildlife that does not choose to live in oaks can use the oak foliage as material for nest construction.

I have a fascination for all trees, but the stunning beauty, strength and longevity of oak trees (Quercus spp.) has made them perhaps the best known and most admired. Our language is full of sayings that celebrate this impressive species: like "strong as an oak" or "from tiny acorns do mighty oaks grow."

The oak is widespread and also impressive in stature, with species growing to more than 100 feet (30 meters) tall. But where do oaks come from? The history of oak trees starts many million years ago and is a story worth the telling. Read on for the highlights of oak tree history.

Oak Tree History

It's always difficult to put your finger on the exact date - or even the century - a species begins. Usually, a particular kind of tree emerges slowly from a lengthy lineage of trees and shrubs, and this is the case of oaks. But one thing is clear in the history of oak trees: oaks have been around a long time.

Oak trees are in the genus Quercus, which is part of the plant family Fagaceae, a family shared with the beech (Fagus spp.) and the chestnut tree (Castanea spp.) Fossil evidence shows that members of this plant family date back to at least the Late Cretaceous (some 85 million years ago).

However, the first fossils directly related to oak tree history appeared some 32 to 35 million years ago, with similar types of trees to modern-day oaks. These first fossils show the actual oak species appeared some 25 million years ago. Now that's a long history. So oak tree history starts millions of years ago. But exactly where do oaks come from?

It is likely that America can claim oaks as our own, since the earliest fossils were found in the present-day state of Georgia. There are over 600 species of trees and shrubs in the oak genus. All are native to the northern hemisphere, from frigid latitudes to tropical Asia and the Americas.

Oak species can be shrubby or majestic, but most have one thing in common - their fruit, called acorns. Oaks are monoecious, meaning that both the male and female flowers are on the same tree. Male flowers (catkins) appear in early spring, triggering many allergies. Female blooms are barely noticeable but will eventually grow to produce acorns. Acorns consist of two components: a nut and a cupule, the cup-like structures that attach them to the tree branch.

Interestingly, few acorns actually survive long enough to become trees, since a number of wildlife feed on them. This is yet another amazing thing about oak trees - They still find a way to live on. All it takes is one acorn.

Oaks are tough, magnificent trees that are integral parts of many western ecosystems. However, they can be damaged easily if their very specific growth requirements are altered. This often happens when homeowners try landscaping beneath oaks. Can you plant under oak trees? Limited planting under an oak tree is possible as long as you keep the tree’s cultural requirements in mind. Read on for tips.

Landscaping Beneath Oaks

Few trees add more character to a backyard than mature oaks. They anchor the soil, offer shade in hot summers, and also provide room and board for birds and other wildlife.

Mature oaks also take up a lot of space. Their spreading branches cast such deep shade in summer that you may wonder what will grow under oak trees if anything. The best way to address this question is to look at oak woodlands in the wild.

Over their time on the planet oak trees have developed a careful balance with nature. They grow in areas with wet winters and hot, dry summers and have adapted to this climate. These trees soak up water in the wet winters when low soil temperatures keep fungal diseases from developing.

They need little water in summer. An oak getting significant irrigation in the summer can get deadly fungus diseases such as oak root fungus or crown rot, caused by the soil-borne fungus Phytophthora. If you put a lawn under an oak tree and water it, the tree will probably die.

What Will Grow Under Oak Trees?

Given their cultural needs, there are significant limitations to planting under an oak tree. The only type of plants you can consider for landscaping beneath oaks are plant species that do not need water or fertilizer in summer.

If you visit an oak forest, you won’t see extensive vegetation under oaks, but you will see clumping native grasses. You can consider these for landscaping beneath oaks. A few ideas that deal well with summer drought include:

• California fescue (Festuca californica)
• Deer grass (Muhlenbergia rigens)
• Purple needlegrass (Nassella pulchra)

Other plants you may want to consider include:

• Wild lilac (Ceanothus spp.)
• California iris (Iris douglasiana)
• Creeping sage (Salvia sonomensis)
• Coral bells (Heuchera spp.)

In the areas at the dripline that get a little more sun, you can plant manzanita (Arctostaphylos densiflora), wood rose (Rosa gymnocarpa), creeping mahonia (Mahonia repens), evergreen ribes (Ribes viburnifolium), or azaleas (Rhododendron).

Tips for Planting Under an Oak Tree

If you decide to go ahead and put in plants under your oak, keep these tips in mind. Oaks hate to have their soil compacted, drainage patterns changed, or the soil level altered. Take care to avoid doing this.

Keep all plantings a significant distance from the tree trunk. Some experts recommend not planting anything within 6 feet (2 m.) of the trunk, while others suggest that you leave the soil completely undisturbed within 10 feet (4 m.) from the trunk.

That means that all plantings must be done outside this critical root area, near the tree’s dripline. It also means that you should not irrigate this area in summer at all. You can use organic mulches in the root area which can benefit the tree.

Plant diseases in trees can be tricky things. In many cases, symptoms can go unnoticed for years, then seem to cause sudden death. In other cases, the disease may show obvious symptoms on certain plants in the area but then can affect other plants in the same location in completely different ways. Xylella leaf scorch on oaks is one of these confusing, difficult to diagnose diseases. What is xylella leaf scorch? Continue reading to learn more about oak bacterial leaf scorch.

What is Xylella?

Xylella leaf scorch is a bacterial disease caused by the pathogen Xylella fastidiosa. This bacteria is believed to spread by insect vectors, such as leafhoppers. It can also be spread from grafting with infected plant tissues or tools. Xylella fastidiosa can infect hundreds of host plants, including:

• Oak
• Elm
• Mulberry
• Sweetgum
• Cherry
• Sycamore
• Maple
• Dogwood

In different species, it causes different symptoms, earning it different common names. When xylella infects oak trees, for instance, it is called oak bacterial leaf scorch because the disease causes the leaves to look as if they’ve been burned or scorched. Xylella infects the vascular system of its oak host plants, inhibiting the flow of xylem and causing the foliage to dry out and decline. Olive green to brown colored necrotic patches will first form on the tips and margins of oak leaves. The spots may have light green to reddish brown halos encircling them. The foliage will turn brown, dry out, look crunchy and burnt, and drop prematurely.

Treating an Oak Tree with Xylella Leaf Scorch

Symptoms of xylella leaf scorch on oak trees can appear on just one limb of the tree or be present throughout the canopy. Excessive water sprouts or weepy black lesions may also form on infected limbs. Oak bacterial leaf scorch can kill a healthy tree in just five years. Red and black oaks are specifically at risk. In its advanced stages, oak trees with xylella leaf scorch will decline in vigor, develop stunted foliage and limbs, or have delayed bud break in the spring. Infected trees are usually just removed because they look so terrible. Oak trees with xylella leaf scorch have been found throughout the eastern United States, in Taiwan, Italy, France, and other European countries. At this point, there is no cure for the worrisome disease. Annual treatments with the antibiotic Tetracycline alleviate the symptoms and slows down progress of the disease, but does not cure it. However, the United Kingdom has launched an extensive research project to study xylella and oaks infected by it to protect their nation’s beloved oak trees.

Have you ever wondered what corks are made of? They are often made from the bark of cork oak trees, hence the name. The thick bark is stripped off the living trees of this unique oak species, and the trees regrow a new layer of bark. For more cork oak information, including tips about growing a cork oak tree, read on.

Cork Oaks in the Landscape

Cork oak trees (Quercus suber) are native to the western Mediterranean region and are still cultivated there for their bark. These trees are slow-growing giants, eventually maturing to 70 feet (21 m.) or taller and equally wide. Woody and upright, cork oaks in the landscape have small, rounded leaves that are gray underneath. According to cork tree information, the leaves stay on the branches all winter long, then fall in spring as the new leaves appear. Cork oak trees produce small acorns that are edible. They also grow the fascinating corky bark for which they are cultivated commercially.

Cork Tree Cultivation

If you want to cork oaks around your home, it may be possible to grow these trees. Cork oak cultivation is possible in U.S. Department of Agriculture plant hardiness zones 8 through 10. So, if you are interested in growing a cork oak tree, you’ll need to find a site with full sun and good drainage. The soil should be acidic, since the tree’s leaves yellow in alkaline soil. You can grow cork oak trees by planting acorns if you can’t find a seedling plant. Young cork oak trees grow slowly and require regular irrigation. As the trees mature, they become drought tolerant. Still, even mature trees need a few good soakings per month over the course of the growing season. These make excellent shade trees, as their canopies, full of small leaves, offer moderate to dense shade. Likewise, healthy trees are easy maintenance. You don’t need to prune them unless you want to elevate the base of the canopy.

My oak tree has ridged, knobby, sticky looking formations on the acorns. They’re pretty odd looking and make me wonder what’s wrong with my acorns. As with every earth shattering question, I went directly to the internet to find out why my acorns are deformed. After Googling ‘what causes deformed acorns on oak trees,’ I came across something about knopper galls on oak trees. After reading through the knopper gall information, I’m pretty sure I’ve found the culprit.

Knopper Gall Information

If you, too, have ever asked, “what’s wrong with my acorns,” then this is the most likely culprit. Knopper galls are caused by a Cynipid gall wasp, which is actually rarely seen. The wasp (Andricus quercuscalicis) lays eggs within the tree buds. Found on the pedunculate or common oak tree, these galls may be found on the foliage, twigs, and acorns. The name ‘knopper galls’ is thought to come from the old English word ‘knop,’ meaning a small, rounded protuberance, stud, button, tassel, or the like, and the German word ‘knoppe,’ which refers to a kind of felt cap worn during the 17th century. At any rate, my galls look rather like green, sticky, walnut meat. Yep, I think I’ve discovered what causes deformed acorns on oak trees.

Why are My Acorns Deformed?

So, after reading a bit, I found out that knopper galls on oak trees usually present as an abnormal tissue growth or swelling on the acorns, twigs, or leaves. Check. It starts out when the wasp lays its eggs in the bud. The tree’s reaction is to increase the production of its growth hormones. This makes the growth and development of the nut, or acorn, go a bit haywire, resulting in these wavy, knobby formations. In turn, the gall protects and feeds the gall maker – which, in this case, is the wasp larva. The galls are usually seen from spring to summer when the wasp is actively laying eggs. Although the galls have a negative effect on the reproduction of the tree, they don’t harm the overall health of the oak. Therefore, no treatment is required.

Many gardeners are not familiar with nuttall oak trees (Quercus nuttallii). What is a nuttall oak? It is a tall deciduous tree native to this country. For more nuttall oak information, including tips on how to grow a nuttall oak, read on.

Nuttall Oak Information

These trees are in the red oak family. They grow to 60 feet (18 m.) tall and 45 feet (14 m.) wide. As native trees, they require minimal nuttall oak tree care. Vigorous and strong, nuttall oaks grow in a pyramidal form. They later mature into a round-canopied tree. The tree’s upper branches tip upward, while lower limbs grow straight out horizontally without drooping. Like most oak trees, a nuttall oak has lobed leaves, but they are smaller than the leaves of many oaks. Nuttall oak information suggests that the leaves grow in red or maroon, then mature into deep green. In autumn, they turn red once again before falling to the ground in winter. You can identify this tree best by its unique acorn. It is about one inch (2.5 cm.) long and almost as wide. The acorns are plentiful and brown with caps that cover almost half of the acorn base. Squirrels and other mammals eat the acorns.

How to Grow a Nuttall Oak

Growing nuttall oak trees is a good idea for gardeners desiring tall shade trees. The species thrives in USDA plant hardiness zones 5 through 9, and in those regions, the trees won’t need much nuttall oak care. The first step in growing this tree is to locate a large enough site. Take into account the tree’s mature size. It can grow to 80 feet (24 m.) tall and 50 (15 m.) feet wide. Don’t plan on growing nuttall oak trees in small garden areas. In fact, these tall, easy-care trees are often planted in large parking lot islands, buffer strips around parking lots, or in highway median-strips. Plant the acorns or seedlings in garden areas that get full sun. Soil type is less important, as these native trees tolerate wet or dry soil. They do, however, grow best in acidic soil.

Willow oak trees are very popular shade and specimen trees. Since they are fast growing and fill out with an attractive, branching shape, they are a frequent choice in parks and along wide streets. Keep reading to learn more about how to grow a willow oak and willow oak tree care.

Willow Oak Information

Willow oak trees (Quercus phellos) are native to the United States. They are hardy in USDA zones 5 or 6a through 9b, making their range the whole of the west coast, most of the east coast, and the entire south and southwest.

The trees are fast growing. When they are young, they have a pyramidal shape, but as they mature their branches take on a wide, even spread. The lowest branches hang down somewhat toward the ground. The trees tend to reach a height of 60 to 75 feet (18-23 m.) with a spread of 40 to 50 feet (12-15 m.).

The leaves, unlike other oak trees, are long, thin, and dark green, similar looking in appearance to willow trees. In the autumn, they turn yellow to bronze in color and eventually drop. The trees are monoecious and produce flowers (catkins) in the spring that can lead to some litter. The fruits are small acorns, no bigger than ½ an inch (1 cm.) across.

Willow Oak Tree Care

Growing willow oak trees is easy and very rewarding. While they prefer moist, well-drained soil, they will thrive in almost any kind of soil and are wind, salt, and drought tolerant, making them popular in urban landscapes lining broad streets or filling in parking lot islands.

They prefer full sun. They are, for the most part, resistant to both pests and diseases. Though they are drought tolerant, they will also perform well in soil that is perpetually wet. They’ve been used for decades as urban, street lining trees and have proven themselves to be up to the task.

It should be noted that in smaller areas, it may be best to avoid the tree, as its height can eventually overpower the area.

Mighty and majestic, the bur oak (Quercus macrocarpa) is a survivor. Its massive trunk and rough bark help it exist in a very broad natural range in a variety of habitats – from wet bottomlands to dry uplands. What is a bur oak? Read on for bur oak information and tips on bur oak care.

What is a Bur Oak?

Bur oaks, also called mossycup oak, are decidedly impressive oak trees native to North America. They grow in the wild in central and eastern sections of the continent. The common names come from a mossy scale, or bur, on the acorn cup rim.

Bur Oak Information

Bur oak trees are medium to large sized trees. They are deciduous members of the white oak group and grow to heights between 60 and 150 feet tall (18-46 m.). If you are thinking of planting a bur oak, you’ll want to take height into account when selecting a site. Keep in mind that the trees also have broad, rounded crowns. Bur oak trees produce yellow catkin flowers in springtime, but they are not particularly showy. The acorns are oval with fringed cups, and offer a good food source for wildlife, including both birds and mammals. Don’t expect brilliant fall color in bur oak tree leaves. The green leaves turn a dull yellow-brown before they fall.

Planting a Bur Oak

Planting a bur oak is only a good idea for homeowners with very large backyards, given the size of the trees. The massive oak grows best in U.S Department of Agriculture zones 3 through 8. Be sure you site the tree with enough room to grow and in a permanent location. Bur oak information says that these native trees can live up to 300 years. If you do decide to start planting a bur oak, site the tree in full direct sun. Be sure the tree gets at least six hours of unfiltered sunlight every day. For best bur oak care, plant the tree in soil that is well drained and loamy. It will grow in either acidic or alkaline soil, and tolerates sandy, wet, and clay soils. Speaking of bur oak care, don’t forget to water the tree regularly, especially during its first year in your garden. Bur oak trees have some drought tolerance, but they will grow faster and healthier with moderate moisture. Note that bur oak trees tolerate city smoke and other air pollutants as well as compacted soil. They are often used as shade trees on U.S. city streets.

Oak leaf gall mites are more of a problem for humans than for oak trees. These insects live inside the galls on oak leaves. If they leave the galls in search of other food, they can be a true nuisance. Their bites are itchy and painful. So exactly what are oak leaf mites? What is effective in treating oak mites? If you want more information on how to get rid of oak mites, also called oak leaf itch mites, read on.

What are Oak Leaf Mites?

Oak tree gall mites are tiny parasites that attack gall larvae on oak leaves. When we say tiny, we mean tiny! You may not be able to spot one of these mites without a magnifying glass. The female and male oak tree gall mites mate. Once the females are fertilized, they enter the gall and paralyze the larvae with their venom. The female mites then feed on the larvae until their offspring emerge. An entire generation of oak mites can emerge in a single week, which means that the mite population can swell rapidly. Once the oak tree gall mites have eaten the gall larvae, they leave in search of other food. Even if they don’t run out of food, mites may leave the galls. They may fall from the tree or be blown off by a breeze. This usually happens late in the season when the mite population is very large. Some 300,000 mites can fall from each tree every day.

Oak Mite Control

Oak tree gall mites can enter a house through open windows or screens and bite people inside. More often, however, the mites bite people while working outdoors in the garden. The bites usually occur on the upper body or wherever clothing is loose. They are painful and itch a lot. People who are not aware of oak tree gall mites think they have been bitten by bed bugs. You might think that spraying the oak tree would be an effective oak mite control, but this is not the case. The oak tree gall mites actually live inside the galls. Since tree sprays do not penetrate the galls, the mites are safe from sprays. If you are wondering how to get rid of oak mites, there is no perfect solution. You can try to exercise oak mite control by using DEET, a commercially available mosquito and tick repellent. In the end though, you can only protect yourself best by being vigilant. Stay away from oak trees with galls toward the end of summer. When you do go into the garden or near the trees, shower and wash your clothes in hot water when you come in from gardening.

White oak trees (Quercus alba) are North American natives whose natural habitat extends from southern Canada down to Florida, over to Texas, and up to Minnesota. They are gentle giants that can reach 100 feet (30.5 m.) in height and live for centuries. Their branches provide shade, their acorns feed wildlife, and their fall colors dazzle everyone who sees them. Keep reading to learn some white oak tree facts and how to include white oak trees in the landscape of your home.

White Oak Tree Facts

White oak trees get their name from the whitish color of the undersides of their leaves, distinguishing them from other oaks. They are hardy from USDA zone 3 through 9. They grow at a moderate rate, from 1 to 2 feet (31-61 cm.) per year, reaching between 50 and 100 feet (15-30.5 m.) tall and 50 to 80 feet (15-25 m.) wide at maturity. These oak trees produce both male and female flowers. The male flowers, called catkins, are 4 inch (10 cm.) long, yellow clusters that hang down from the branches. The female flowers are smaller red spikes. Together, the flowers produce large acorns that reach over an inch (2.5 cm.) long. The acorns are a favorite of a wide variety of native North American wildlife. In the fall, the leaves turn striking shades of red to deep burgundy. Especially on young trees, the leaves may stay in place all through the winter.

White Oak Tree Growing Requirements

White oak trees can be started from acorns sown in the fall and heavily mulched. Young seedlings can also be planted in the spring. White oak trees have a deep taproot, however, so transplanting after a certain age can be very difficult. White oak tree growing conditions are relatively forgiving. The trees like to have at least four hours of direct sunlight per day, though in the wild young trees will grow for years in the forest understory. White oaks like deep, moist, rich, slightly acidic soil. Due to their deep root system, they can tolerate drought reasonably well once they are established. They do not, however, do well in poor, shallow, or compacted soil. Plant the oak tree somewhere where the soil is deep and rich, and the sunlight is unfiltered for the best results.

“Today's mighty oak is just yesterday's nut, that held its ground,” said author David Icke. Pin oak trees are mighty oaks that have held their ground as a fast growing, native shade tree in the eastern part of the United States for hundreds of years. Yes, that’s right, I did just use “fast growing” and “oak” in the same sentence. Not all oaks are as slow growing as we generally think they are. Continue reading to learn about pin oak growth rate and using pin oaks in landscapes.

Pin Oak Information

Native east of the Mississippi River and hardy in zones 4 through 8, Quercus palustris, or pin oak, is a large, full, ovate shaped tree. With a growth rate of 24 inches (61 cm.) or more per year, it is one of the faster growing oak trees. Tolerant of wet soils, pin oak trees usually grow 60 to 80 feet (19-25 m.) high and 25 to 40 feet (8-12 m.) wide – though in the right soil conditions (moist, rich, acidic soil), pin oaks have been known to grow over 100 feet (30.5 m.) tall. A member of the red oak family, pin oaks will not grow in areas of high elevation or on slopes. They are usually found in damp lowlands and near rivers, streams, or lakes. Pin oak acorns are often dispersed far from the parent plant and germinated by spring flooding. These acorns, as well as the tree’s leaves, bark, and flowers, are a valuable food source to squirrels, deer, rabbits, and various game and songbirds.

Growing Pin Oaks in Landscapes

During the summer, pin oak trees have dark green, glossy leaves that turn a deep red to bronze color in the fall and hang on throughout winter. The beautiful foliage hangs from thick, dense branches. Having a rather ovate shape that turns more pyramidal with age, pin oaks’ lower branches hang down, while the middle branches reach out horizontally and the upper branches grow upright. These pendulous lower branches can make pin oak a not-so-good choice for street trees or small yards. What makes pin oak an excellent tree for large landscapes is its quick growth, beautiful fall color, and winter interest. It also has the ability to provide dense shade, and its shallow fibrous roots make planting a pin oak tree easy. On young trees, the bark is smooth, with a red-gray color. As the tree ages, the bark becomes darker gray and deeply fissured. Pin oaks can develop iron chlorosis if soil pH is too high or alkaline, which causes leaves to turn yellow and drop prematurely. To correct this, use acidic or iron rich soil amendments or tree fertilizers. Other problems pin oaks can develop are:

• Gall
• Scale
• Bacterial leaf scorch
• Oak wilt
• Borers
• Gypsy moth infestations

Call a professional arborist if you suspect any of these conditions with your pin oak.

Water oaks are native to North America and found across the American South. These medium sized trees are ornamental shade trees and have an ease of care that makes them perfect in the landscape. Try growing water oak trees as street plants or primary shade trees but be aware that these plants are short-lived and can be assumed to survive 30 to 50 years. Read the article below for more water oak information.

Water Oak Information

Quercus nigra is a tolerant plant that can grow in partial shade or sun to full sun. These elegant trees are deciduous to semi-evergreen and an important part of ecosystems from New Jersey to Florida and west to Texas. Water oaks grow at a fantastic rate of up to 24 inches (61 cm.) per year. Caring for a water oak is easy, but it is a weak wooded tree prone to many diseases and insect pests. Water oaks produce copious quantities of acorns, which are a favorite food of squirrels, raccoons, turkeys, pigs, ducks, quail, and deer. Deer also browse young stems and twigs in winter. The trees tend to develop hollow stems, which are habitats for a host of insects and animals. In the wild, it is found in lowlands, flood plains, and near rivers and streams. It has the capacity to thrive in compact or loose soil, provided there is adequate moisture. Water oaks may be short-lived, but their rapid growth makes them an excellent shade tree for decades. However, special water oak tree care when young is essential to produce a strong scaffold. Both pruning and staking may be necessary to help the tree develop a sturdy skeleton.

Growing Water Oak Trees

Water oaks are so adaptable they are often used as residential, reclamation, or even drought zone trees. They may be planted in areas with pollution and poor air quality and the tree still thrives. The trees are reliably hardy in USDA zones 6 to 9. Water oaks get 50 to 80 feet (15-24 m.) tall with a nice cone-shaped crown. Bark ages to brownish black and is thickly scaled. Male flowers are insignificant but female catkins appear in spring and become wide, ½ inch (1 cm.) long acorns. The leaves are oblong, spatulate, and deeply tri lobed. Foliage may grow 2 to 4 inches (5-10 cm.) long. These trees are extremely adaptable and, once established, caring for a water oak is reduced to handling any pest or disease issues and providing supplemental water during extremely dry periods.

Water Oak Tree Care

Water oaks must be trained when young to prevent the crotch from splitting due to poor collar formation and the weight of the side limbs. Young trees should be trained to a central trunk for best plant health. The rapid growth of the plant contributes to its weak wood, which is often hollow by its 40th year. Provide young trees with plenty of water to ensure good cell development and thick wood. Oaks are host to a number of pest and disease issues. Caterpillars, scale, galls, and borers are the insects of most concern. Oak wilt is the most serious disease, but many fungal issues are often present. These might include powdery mildew, canker, leaf blight, anthracnose, and fungal leaf spot. A common deficiency in iron causes chlorosis and yellowing of the leaves. Most issues aren't serious and can be combated by good cultural care.

Sudden oak death is a deadly disease of oak trees in coastal areas of California and Oregon. Once infected, trees can’t be saved. Find out how to protect oak trees in this article.

What is Sudden Oak Death?

The fungus that causes sudden oak death (Phytophthora ramorum) results in a quick death for tanoaks, California black oaks, and live oaks along the coast of California and Oregon. The fungus also infects the following landscape plants:

• Bay laurel
• Huckleberry
• California buckeye
• Rhododendron

Here are the symptoms of sudden oak death:

• Cankers on the stems and branches.
• Leaves in the crown that turn pale green, then yellow, then brown.
• Cankers that bleed and ooze.

In the alternative species, it causes non-fatal leaf spot or twig dieback instead of the bleeding cankers it causes in oaks. Sudden oak death can infect other species of oak, but those species don’t grow in habitats where the fungus is found, so for now, it isn’t a problem. Since P. ramorum has been identified in nursery stock in California, Oregon, and Washington, there is a possibility of the disease spreading to other parts of the country.

Sudden Oak Death Information

This disease is always fatal in susceptible oak species and there is no cure. Sudden oak death treatment focuses on prevention and protection. Here are a few things you can do to protect your susceptible oaks:

• Allow 15 feet (4.5 m.) between the trunk of an oak tree and other susceptible species, such as bay laurel and rhododendron.
• Spray the fungicide Agri-fos to protect oak trees. This is a preventative spray, not a cure.
• Don’t plant new oak trees in areas with known infection.

If you think your yard is too small for oak trees, think again. Columnar oak trees (Quercus robur ‘Fastigiata’) offer the magnificent green lobed foliage and ridged bark that other oaks have, without taking up all that space. What are columnar oak trees? They are slow-growing, slender oaks with a tight, upright and narrow profile. Read on for more columnar oak information.

What are Columnar Oak Trees?

These unusual and attractive trees, also called upright English oak trees, were first found growing wild in a forest in Germany. These types of columnar oaks were propagated by grafting. Columnar oak tree growth is moderately slow, and the trees grow up, not out. With these trees, you don’t have to worry about the spreading lateral branches you associate with other oaks. Columnar oak trees might grow to 60 feet (18 m.) tall, but the spread will remain about 15 feet (4.5 m.). The dark green leaves turn brown or yellow in autumn and remain on the tree for months before they fall in winter. The trunk of the columnar oak is covered in dark brown bark, deeply ridged, and very attractive. The tree has small acorns hanging on the branches most of the winter that attract squirrels.

Columnar Oak Information

These ‘fastigata’ types of columnar oaks are easy care trees with outstanding ornamental qualities. Since the columnar oak tree growth direction is up, not out, they are useful in areas where you don’t have room for wide trees; the crown of the columnar oak remains tight, and no branches break out of the crown and wander out from the trunk. Ideal columnar oak tree growth conditions include a sunny location. Plant these oaks in direct sun on well-drained acidic or slightly alkaline soil. They are extremely adaptable and very tolerant of urban conditions. They also tolerate drought and aerosol salt.

Caring for Columnar Oak Trees

You will find that caring for columnar oak trees is not difficult. The trees tolerate drought but do best with occasional irrigation. These are good trees for cooler climates. They thrive in U.S. Department of Agriculture plant hardiness zones 4 or 5 through 8.

If you want a graceful, spreading shade tree that is an American native, live oak (Quercus virginiana) might be the tree you are looking for. Live oak tree facts give you some idea of how impressive this oak might be in your backyard. The tree grows some 60 feet (18 m.) tall, but the strong, sinuous branches can spread to 120 feet (37 m.) wide. Read on for further information about how to grow a live oak tree and live oak tree care.

Live Oak Tree Facts

If you are thinking of a live oak tree growing in your garden, consider the size, shape, and other live oak tree facts before you jump in. With its deep, inviting shade, the live oak looks like it belongs in the Old South. It is, in fact, the state tree of Georgia. This mighty tree’s crown is symmetrical, rounded, and dense. The leaves grow in thickly and hang on the tree until spring, when they yellow and fall. Its beauty aside, the live oak is a tough, enduring specimen that can live for several hundred years if planted and cared for correctly. However, the tree is vulnerable to the fatal oak wilt disease, spread by insects and infected pruning tools.

Live Oak Tree Growing

Learning how to grow a live oak tree is not difficult. Perhaps, the most important thing is finding a site with sufficient space to accommodate the tree at its mature size. In addition to the height of the tree and spread of the branches, the trunk itself can grow to 6 feet (2 m.) in diameter. The wide surface roots might in time lift sidewalks, so plant it away from the house. The live oak tree is undemanding. You can start a live oak tree growing in partial shade or sun. Don’t fret about soil. Although live oaks prefer acidic loam, the trees accept most types of soil, including sand and clay. They grow in alkaline or acidic soil, wet or well-drained. You can even grow live oak by the ocean, as they are tolerant of aerosol salt. Live oaks resist strong winds and are drought tolerant once established.

Caring for Live Oaks

When you get your live oak tree growing, you need to think about live oak care. This includes regular irrigation while the tree is establishing its root system. It also includes pruning. It is critical for this giant oak to develop a strong branch structure while it is young. Prune out multiple leaders to leave one trunk and eliminate branches that form sharp angles with the trunk. Caring for live oaks properly means pruning the trees each year for the first three years. Never prune in early spring or the first month of summer to avoid attracting the insects that spread oak wilt disease.

Almost everyone who lives near oak trees has seen the small balls hanging in the tree branches, yet many still may ask: “What are oak galls?” Oak apple galls look like small, round fruit but they are actually plant deformities caused by oak apple gall wasps. The galls generally do not damage the oak tree host. If you want to know how to get rid of oak galls, read on for oak apple gall treatment.

Oak Apple Gall Information

So what are oak galls? Oak apple galls appear in oak trees, most often black, scarlet, and red oaks. They get their common name from the fact that they are round, like small apples, and hang in the trees. Oak apple gall information tells us that galls are formed when a female oak apple gall wasp lays eggs in the central vein on an oak leaves. When the larvae hatch, chemical and hormone interaction between the wasp eggs and the oak causes the tree to grow the round gall. Galls are essential to developing oak apple gall wasps. The gall provides a safe home as well as food for the young wasps. Each gall contains only one young wasp. If the galls you see are green with brown spots, they are still forming. At this stage, the galls feel a little rubbery. The galls get bigger as the larvae get bigger. When the galls dry out, the oak apple gall wasps fly from small holes in the galls.

Oak Apple Gall Treatment

Many homeowners assume that the galls damage the oak trees. If you think so, you’ll want to know how to get rid of oak galls. It is true that oak trees look odd after their leaves fall and the branches are hung with galls. However, the oak apple galls do not injure the tree. At the worst, a severe infestation might make leaves fall early. If you still want to know how to get rid of oak gall wasps, you can rid the tree of galls by snipping them off with a sterilized pruner before they are dry.

Northern red oak (Quercus rubra) is a handsome, adaptable tree that thrives in nearly any setting. Planting a red oak tree requires a bit of extra preparation, but the payoff is great; this American classic provides glorious summer shade and reliable fall color for many years to come. Read on for red oak tree information, then learn how to grow a red oak tree.

Red Oak Tree Characteristics and Info

Red oak is a hardy tree suitable for growing in USDA plant hardiness zones 3 through 8. This moderately fast-growing oak tree reaches mature heights of 60 to 75 feet (19-23 m.), with a spread of 45 to 50 feet (14-15 m.). The tree is valued for its deep root system, which makes it useful for planting near urban streets and sidewalks.

How to Grow a Red Oak Tree

Planting a red oak tree is best done in spring or fall so the roots have time to settle in before the arrival of hot, dry weather. Select a planting space carefully so the tree won’t interfere with buildings or power lines. As a general rule, allow at least 20 feet (6 m.) in each direction. Ensure the tree is exposed to at least six hours of direct sunlight every day. In its natural environment, red oak has a symbiotic relationship with various fungi, which provides the roots with moisture and minerals. The best way to replicate this natural soil environment is to dig generous amounts of manure and compost into the soil before planting. This step is especially important in urban areas where the soil may be depleted. Plant the tree in a hole at least twice as wide as the root ball, then fill the hole with a soil/compost mixture. Water the tree deeply and slowly to ensure the area around the root ball is saturated. A thick layer of bark mulch will keep the roots cool and moist. Protect young red oak trees with a fence or cage if you have hungry rabbits or deer in the neighborhood.

Care of Red Oak Trees

Care of red oak trees is minimal, but a new tree requires regular moisture, especially during hot, dry weather. Water the tree deeply once every week in the absence of rainfall. Established trees are relatively drought tolerant. Treat young red oak trees with a commercial fungicide if you notice powdery mildew during warm, humid weather. Watch for aphids, which are usually easy to remove by spraying the foliage with a strong stream of water. Otherwise, use an insecticidal soap spray.

Willow oaks are no relation to willows but they seem to soak up water in a similar fashion. Where do willow oak trees grow? They thrive in floodplains and near streams or marshes, but the trees are remarkably drought tolerant, too. One of the interesting facts about willow oak trees is their relation to red oaks. They are in the red oak group but do not have the characteristic lobed leaves of the red oaks. Instead, willow oaks have narrow willow-like leaves with a bristle-like hair at the end of the foliage that characterizes them as oaks.

Willow Oak Tree Information

Willow oaks (Quercus phellos) are popular shade trees in parks and along streets. This tree grows fairly quickly and can become too large for some urban settings. The plant tolerates pollution and drought and has no serious insect or pest problems. The main factors for good willow oak tree care are water at establishment and some support when young. Willow oaks develop nicely symmetrical pyramid to round crown shapes. These attractive trees can grow up to 120 feet (37 m.) in height but are more commonly found at 60 to 70 feet (18-21 m.). The root zone is shallow, which makes it easy to transplant. The delicate leaves create dappled shade and produce a golden yellow color show in fall before they drop. Leaves are 2 to 8 inches (5-23 cm.) long, simple and entire. Willow oaks produce small acorns of ½ to 1 inch (1-3 cm.) in length. It takes 2 years for these to mature, which is a unique bit of willow oak tree information. These are very attractive to squirrels, chipmunks and other ground foragers. You can consider this one of willow oak trees pros, and also cons where ground litter is concerned.

Where Do Willow Oak Trees Grow?

Willow oaks are found from New York south to Florida and west to Texas, Oklahoma and Missouri. They occur in flood lands, alluvial plains, moist forest, stream banks and bottomlands. The plant thrives in moist acidic soils of almost any type. Willow oaks require full sun. In partial shade situations, the crown will develop into a weakly branched slender form as limbs reach for the sun. In full sun, the plant spreads out its limbs and makes a more balanced shape. For this reason, pruning young trees in low light is part of good willow oak care. Training early helps the tree form a strong structure.

Willow Oak Tree Pros and Cons

As a shade specimen in large public spaces, willow oak really can’t be beat for beauty and ease of management. But one of the facts about willow oak trees is their high water needs, especially when young. This can mean the tree will pirate moisture from other plants in the area. It is also a fast grower and can suck the local nutrients out of the soil as fast as they can be replaced. None of this is good for nearby flora. The dropped leaves in fall and acorns on the ground may be considered a nuisance. The animals attracted by the nuts are either cute to watch or annoying rodents. Additionally, the tree's large size may not be appropriate for the home landscape, and some of the tree’s peculiarities may be more than you are prepared to live with. Either way you look at it, willow oak is definitely a strong, versatile tree with good wind resistance and ease of care; just make sure it’s the right tree for your garden/landscape space.

Don’t look for the typical lobed oak leaves to identify chinkapin oak trees (Quercus muehlenbergii). These oaks grow leaves that are toothed like those of chestnut trees and are often misidentified because of this. On the other hand, some facts about chinkapin trees help you recognize them as part of the oak tree family. For example, chinkapin oak trees, like all oaks, grow clusters of buds at the end of branches. Read on for more chinkapin oak information.

Facts About Chinkapin Trees

Chinkapins are native to this country, growing naturally in the wild from New England to the Mexican border. As part of the group of white oaks, they bear very pale, white bark. Their trunks can grow to 3 feet (1 m.) in diameter.

Chinkapins are not small trees, growing to 80 feet (24 m.) in the wild and 50 feet (15 m.) tall when cultivated. The breadth of the open, rounded canopy tends to approximate the height of the tree. These oaks are planted extensively as shade trees in appropriate hardiness zones.

The leaves of the chinkapin oak tree are particularly lovely. The tops of the leaves are yellow-green, while the undersides are pale silver. The leaves flutter like those of aspens in the breeze. In the fall, the leaves turn bright yellow, contrasting beautifully with the white bark.

Chinkapin acorns appear without stalks, and they mature in just one season. They are between ½ inch and 1 inch (1-2.5 cm.) long and are edible if cooked. The wood of these oaks is hard and durable. It is known to make a fine polish and is used for furniture, fencing, and barrels.

Additional Chinkapin Oak Information

Growing a chinkapin oak tree is easier if you start the young tree in its permanent site. These oaks are difficult to transplant once established.

Plant chinkapin in a location with full sun and well-draining soil. The species prefers moist, fertile soils, but tolerates many different types of soil. It is one of the only white oak trees to accept alkaline soils without developing chlorosis.

Care for chinkapin trees is easy once they are established. Irrigate this native tree only if the weather is very hot or dry. It has no serious disease or insect problems so requires no spraying.

Oaks (Quercus) come in many shapes and sizes, and you'll even find a few evergreens in the mix. Whether you are looking for the perfect tree for your landscape or want to learn to identify the different types of oak trees, this article can help.

Oak Tree Varieties

There are dozens of oak tree varieties in North America. The varieties are divided into two main categories: red oaks and white oaks.

Red Oak Trees

Reds have leaves with pointed lobes tipped with tiny bristles. Their acorns take two years to mature and sprout the spring after they drop to the ground. Common red oaks include:

• Willow oak

• Black oak

• Japanese evergreen oak

• Water oak

• Pin oak

White Oak Trees

The leaves on white oak trees are rounded and smooth. Their acorns mature in one year and they sprout soon after they fall to the ground. This group includes:

• Chinkapin

• Post oak

• Bur oak

• White oak

Most Common Oak Trees

Below is a list of oak tree types that are the most commonly planted. You'll find that most oaks are massive in size and not suitable for urban or suburban landscapes.

• White Oak Tree (Q. alba): Not to be confused with the group of oaks called white oaks, the white oak tree grows very slowly. After 10 to 12 years, the tree will stand only 10 to 15 feet tall (3-5 m.), but it will eventually reach a height of 50 to 100 feet (15-30 m.). You shouldn't plant it near sidewalks or patios because the trunk flairs at the base. It doesn't like to be disturbed, so plant it in a permanent location as a very young sapling, and prune it in the winter while it is dormant.
• Bur Oak (Q. macrocarpa): Another massive shade tree, the bur oak grows 70 to 80 feet tall (22-24 m.). It has an unusual branch structure and deeply furrowed bark that combine to keep the tree interesting in winter. It grows farther north and west than other white oak types.
• Willow Oak (Q. phellos): The willow oak has thin, straight leaves similar to those of a willow tree. It grows 60 to 75 feet tall (18-23 m.). The acorns aren't as messy as those of most other oaks. It adapts well to urban conditions, so you can use it a street tree or in a buffer area along highways. It transplants well while it is dormant.
• Japanese Evergreen Oak (Q. acuta): The smallest of the oak trees, the Japanese evergreen grows 20 to 30 feet tall (6-9 m.) and up to 20 feet wide (6 m.). It prefers the warm coastal areas of the southeast, but it will grow inland in protected areas. It has a shrubby growth habit and works well as a lawn tree or screen. The tree provides good quality shade despite its small size.
• Pin Oak (Q. palustris): The pin oak grows 60 to 75 feet tall (18-23 m.) with a spread of 25 to 40 feet (8-12 m.). It has a straight trunk and a well-shaped canopy, with the upper branches growing upward and lower branches drooping down. The branches in the center of the tree are nearly horizontal. It makes a wonderful shade tree, but you may have to remove some of the lower branches to allow clearance.

Oak trees (Quercus) are among the most common tree species found in forests, but their numbers are declining. The main cause of the decline is the value of acorns and young saplings as a food source for wildlife. You can help the tree recover its former glory by starting and planting oak tree seedlings following the instructions in this article.

Propagating Oak Trees

For convenience, the many species of oak are divided into two main groups: red oaks and white oaks. You can tell which group an oak belongs to by taking a close look at the leaves. Red oak leaves have pointed lobes with little bristles at the tips, while the lobes on white oak leaves are rounded. Propagating oak trees is good for the environment and it's an easy, fun project for kids. All you need is an acorn and a gallon (4 L.) pot filled with soil. Here are the steps for growing oak trees from acorns.

How to Grow an Oak Tree

Don't gather the first acorns that fall. Wait until the second flush begins to fall, and then collect several handfuls. You might think you are collecting a lot more than you need, but the germination rates for acorns is low, so you need lots of extras. Check the leaves to determine whether you are collecting white oak or red oak acorns and label the containers if you collect some of each. Visually examine your acorns and throw away any that have small holes where an insect may have bored in, as well as those that are off colored or moldy. The caps of mature acorns come off easily. Go ahead and remove them during your visual inspection. Soak the acorns in a container of water overnight. Damaged and immature seeds float to the top, and you can scoop them off and discard them. White oak acorns are ready for planting right after soaking, but red oak acorns need a special treatment called stratification. Place the red oak acorns in a zipper bag with moist sawdust or peat moss. You don't want the sawdust or peat moss soaking wet, just lightly damp. Leave them for eight weeks, checking every two weeks or so to make sure they aren't molding. Remove molded acorns and leave the bag open to allow fresh air in if you see signs of mold. Fill pots that are at least 12 inches (31 cm.) deep with potting soil. Plant the acorns an inch (2.5 cm.) deep. You can plant several acorns in each pot. Transplant the seedlings to a permanent location when the first leaves unfurl. If you only have one seedling in the pot, you can keep it indoors in a sunny window for up to three months. If you prefer to plant the acorns directly in the ground, take care to protect them from wildlife.

Oak Tree Care

Early on, oak tree saplings are in danger of being consumed by wildlife. Place cages over newly planted saplings and replace them with chicken wire fences as the sapling grows. Keep the tree protected until it is at least 5 feet (1.5 m.) tall. Keep the area surrounding young oak trees free of weeds and water the soil around the tree in the absence of rain. The tree won't develop strong roots in dry soil. Don't fertilize the tree until its second year after planting. Even then, only use fertilizer if the leaves are pale, or the tree is not growing as it should. Keep in mind that oak trees grow very slowly at first. Feeding the tree to encourage fast growth weakens the wood. This can lead to splits in the trunk and broken branches.

It's a beautiful thing when a landscape comes together, even if it takes many years for your plants to mature into your dream garden. Sadly, many problems can interfere with gardening goals, including oak wilt disease, a serious fungal disease of oak trees. In some areas, oak wilt is becoming endemic, affecting both young and mature oak trees. Read on to learn about this important disease of oaks.

What is Oak Wilt?

Oak wilt is a serious disease of oak trees, caused by the fungal pathogen Ceratocystis fagacearum, which is believed to be native. It can be spread by boring beetles or through root-to-root contact between trees. The fungus grows in the transport tissues of infected trees, making it highly communicable between trees that are sharing connections in their root systems. Red and black oaks are considered highly susceptible to oak wilt and may die completely within four months of initial infection. White oaks are more tolerant, often displaying only vague symptoms of oak wilt disease if they show any at all. These oaks also eventually succumb to oak wilt, but it may linger up to seven years.

How to Diagnose Oak Wilt

Oak wilt disease can be difficult to diagnose without professional help because the symptoms are similar to those found in other diseases, such as anthracnose, boring beetles, lightning damage, and a myriad of environmental stressors. If your tree is suddenly showing yellowing or browning of the leaves of entire branches and is shedding leaves with significant areas of green remaining, it's a good idea to cut a wilted branch or two across the grain. Dark circles in the otherwise lighter inner tissues are a good indicator that you need help and fast. Oak wilt treatment and prevention is serious business, requiring the use of heavy equipment to break your tree's connection to any other oaks within 50 feet (15 m.). Fungicidal injections of propiconazole have shown some promise in uninfected trees in high-risk areas, but this treatment will do little for trees with oak wilt fungus in their root systems. Minimize the risk to your tree from beetle-spread oak wilt spores by pruning only during the winter and painting all wounds with a latex paint as soon as they happen. Bark beetles often find damaged trees within the first three days, attracted by the scent of fresh sap - your timing is vital. Oak wilt is bad enough, but the addition of bark beetles may create a situation that's hopeless for your tree.