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Quercus virginiana
( Live Oak )

The superb shade tree that brings to mind images of old, Southern plantations. Not the best tree for the small lot, but at home on wide open lawns. Do not expect lawns to grow well beneath this tree, as it hogs both sunlight and moisture. Ground covers will be your best solution. Live oaks do not like cold weather. They can be found in all types of soils from the sandy to the very moist. Withstands beach conditions very well. Drops oldest leaves in January, so wait to mulch and clean up around mid February.
Important Info :

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Cultivar:n/a  
Family:Fagaceae  
Size:Height: 40 ft. to 80 ft.
Width: 60 ft. to 100 ft.  
Plant Category:trees,  
Plant Characteristics:spreading,  
Foliage Characteristics:evergreen,  
Foliage Color:dark green,  
Flower Characteristics: 
Flower Color: 
Tolerances:deer, drought, heat & humidity, pollution, rabbits, seashore, wind,  
Bloomtime Range:not applicable  
USDA Hardiness Zone:8 to 10  
AHS Heat Zone:8 to 12  
Light Range:Part Shade to Full Sun  
pH Range:4.5 to 8.5  
Soil Range:Sand to Clay  
Water Range:Semi-Arid to Boggy  

Plant Care

How-tos : Fertilization for Established Plants

Established plants can benefit from fertilization. Take a visual inventory of your landscape. Trees need to be fertilized every few years. Shrubs and other plants in the landscape can be fertilized yearly. A soil test can determine existing nutrient levels in the soil. If one or more nutrients is low, a specific instead of an all-purpose fertilizer may be required. Fertilizers that are high in N, nitrogen, will promote green leafy growth. Excess nitrogen in the soil can cause excessive vegetative growth on plants at the expense of flower bud development. It is best to avoid fertilizing late in the growing season. Applications made at that time can force lush, vegetative growth that will not have a chance to harden off before the onset of cold weather.

Conditions : Full to Partial Sun

Full sunlight is needed for many plants to assume their full potential. Many of these plants will do fine with a little less sunlight, although they may not flower as heavily or their foliage as vibrant. Areas on the southern and western sides of buildings usually are the sunniest. The only exception is when houses or buildings are so close together, shadows are cast from neighboring properties. Full sun usually means 6 or more hours of direct unobstructed sunlight on a sunny day. Partial sun receives less than 6 hours of sun, but more than 3 hours. Plants able to take full sun in some climates may only be able to tolerate part sun in other climates. Know the culture of the plant before you buy and plant it!

Problems : Creating a Water Ring

A water ring, sometimes called a water well, is a mound of compacted soil that is built around the circumference of a planting hole once a plant has been installed. The water ring helps to direct water to the outer edges of a planting hole, encouraging new roots to grow outward, in search of moisture. The height of the mound of soil will vary from a couple of inches for 3 gallon shrubs, to almost a foot for balled and burlapped trees, especially those planted on a slope. Mulch over the ring will help to further conserve moisture and prevent deterioration of the ring itself. Once a plant is established, the water ring may be leveled, but you should continue to mulch beneath the plant.

Conditions : Moist

Moist is defined as soil that receives regular watering to a depth of 18 inch deep, does not dry out, but does not have a drainage problem either.

Conditions : Moist and Well Drained

Moist and well drained means exactly what it sounds like. Soil is moist without being soggy because the texture of the soil allows excess moisture to drain away. Most plants like about 1 inch of water per week. Amending your soil with compost will help improve texture and water holding or draining capacity. A 3 inch layer of mulch will help to maintain soil moisture and studies have shown that mulched plants grow faster than non-mulched plants.

Conditions : Normal Watering for Outdoor Plants

Normal watering means that soil should be kept evenly moist and watered regularly, as conditions require. Most plants like 1 inch of water a week during the growing season, but take care not to over water. The first two years after a plant is installed, regular watering is important for establishment. The first year is critical. It is better to water once a week and water deeply, than to water frequently for a few minutes.

How-tos : Pruning Trees After Planting

It is critical to prune trees correctly from the beginning to assure proper growth and development. Young trees can be transplanted in a number of forms: bare root, balled & burlap and in containers. The more stress the plant undergoes in the transplant process, the more pruning that is required to compensate.

Deciduous trees like maples (those that loose their leaves in the fall) can be dug up and sold with their bare roots exposed. Because most of the root system is lost in digging, sufficient top growth should be removed to compensate for this loss. This may be done at the nursery before you buy the plant or you may have to prune at the time of planting. Select and head back the best scaffold branches, i.e. those branches which will form the main lateral structure of the future mature tree. Remove all other extraneous side branches. If the tree seedling does not have branches, allow it to grow to the desired height of branching then pinch it back to stimulate the lower buds to form branches.

Ball and burlap trees are dug up with their root systems somewhat intact. This was mostly done for conifers and broadleaf evergreens, but has become common for deciduous trees as well. Since some root mass is lost in the digging stage, a light pruning is generally called for. Head back the plant to compensate for this loss and to promote branching.

Trees that are grown in containers generally do not loose roots in the transplanting phase. Therefore you do not generally have to prune them unless there is some root injury or limb damage in the planting process.

Once you have your trees planted, be patient. Do not remove shoots from the trunk early on as these allow the tree to grow more rapidly and also shade the tender young trunk from sun-scald. Wait a few years to begin training the tree to its ultimate form.

How-tos : Staking Trees

Staking is done differently depending on the size and flexibility of the tree, and the windiness of the planting site. Generally only trees that are planted in windy, exposed locations need to be staked. For most trees, a low stake is preferred, to let the tree move naturally. For windy areas or flexible trees, use a high stake. For trees more than 12 feet tall, use two low stakes on opposite sides of the tree or several guy ropes. The ties used need to accommodate growth and not cause bark damage with friction. Buckle-and-spacer ties can be found at garden centers, they are expandable and have a protective spacer. Ties without spacers should be formed into a figure eight to create padding. Latest studies have shown that when staking a tree, provide enough leeway so that the tree can move back and forth in the wind. Stronger roots will develop this way. If the tree can not move back and forth, these important roots will not develop and the tree might fall over during a storm, once stakes are removed. When planting a tree, stake at the time of planting if staking is a necessity.

How-tos : Planting a Tree

Dig out an area for the tree that is about 3 or 4 times the diameter of the container or rootball and the same depth as the container or rootball. Use a pitchfork or shovel to scarify the sides of the hole.

If container-grown, lay the tree on its side and remove the container. Loosen the roots around the edges without breaking up the root ball too much. Position tree in center of hole so that the best side faces forward. You are ready to begin filling in with soil.

If planting a balled and burlaped tree, position it in hole so that the best side faces forward. Untie or remove nails from burlap at top of ball and pull burlap back, so it does not stick out of hole when soil is replaced. Synthetic burlap should be removed as it will not decompose like natural burlap. Larger trees often come in wire baskets. Plant as you would a b&b plant, but cut as much of the wire away as possible without actually removing the basket. Chances are, you would do more damage to the rootball by removing the basket. Simply cut away wires to leave several large openings for roots.

Fill both holes with soil the same way. Never amend with less than half original soil. Recent studies show that if your soil is loose enough, you are better off adding little or no soil amendments.

Create a water ring around the outer edge of the hole. Not only will this conseve water, but will direct moisture to perimeter roots, encouraging outer growth. Once tree is established, water ring may be leveled. Studies show that mulched trees grow faster than those unmulched, so add a 3"" layer of pinestraw, compost, or pulverized bark over backfilled area. Remove any damaged limbs.

Fungi : Rusts

Most rusts are host specific and overwinter on leaves, stems and spent flower debris. Rust often appears as small, bright orange, yellow, or brown pustules on the underside of leaves. If touched, it will leave a colored spot of spores on the finger. Caused by fungi and spread by splashing water or rain, rust is worse when weather is moist.

Prevention and Control: Plant resistant varieties and provide maximum air circulation. Clean up all debris, especially around plants that have had a problem. Do not water from overhead and water only during the day so that plants will have enough time to dry before night. Apply a fungicide labeled for rust on your plant.

Pest : Caterpillars

Caterpillars are the immature form of moths and butterflies. They are voracious feeders attacking a wide variety of plants. They can be highly destructive and are characterized as leaf feeders, stem borers, leaf rollers, cutworms and tent-formers.

Prevention and Control: keep weeds down, scout individual plants and remove caterpillars, apply labeled insecticides such as soaps and oils, take advantage of natural enemies such as parasitic wasps in the garden and use Bacillus thuringiensis (biological warfare) for some caterpillar species.

Fungi : Leaf Spots

Leaf spots are caused by fungi or bacteria. Brown or black spots and patches may be either ragged or circular, with a water soaked or yellow-edged appearance. Insects, rain, dirty garden tools, or even people can help its spread.

Prevention and Control: Remove infected leaves when the plant is dry. Leaves that collect around the base of the plant should be raked up and disposed of. Avoid overhead irrigation if possible; water should be directed at soil level. For fungal leaf spots, use a recommended fungicide according to label directions.



Pest : Scale Insects

Scales are insects, related to mealybugs, that can be a problem on a wide variety of plants - indoor and outdoor. Young scales crawl until they find a good feeding site. The adult females then lose their legs and remain on a spot protected by its hard shell layer. They appear as bumps, often on the lower sides of leaves. They have piercing mouth parts that suck the sap out of plant tissue. Scales can weaken a plant leading to yellow foliage and leaf drop. They also produce a sweet substance called honeydew (coveted by ants) which can lead to an unattractive black surface fungal growth called sooty mold.

Prevention and Control: Once established they are hard to control. Isolate infested plants away from those that are not infested. Cosnult your local garden center professional or Cooperative Extension office in your county for a legal recommendation regarding their control. Encourage natural enemies such as parasitic wasps in the garden.

Glossary : Southeast

Southeast pertains to plants native to parts of or all of the southeastern region of the United States, including lower parts of Virginia, North Carolina, South Carolina, Georgia, Alabama, Mississippi, Louisiana, Florida, Arkansas, Tennessee, eastern Texas.

Glossary : Evergreen

Evergreen refers to plants that hold onto their leaves or needles for more than one growing season, shedding them over time. Some plants such as live oaks are evergreen, but commonly shed the majority of their older leaves around the end of January.

Glossary : Tree

Tree: a woody perennial with a crown of branches that begin atop a single stem or trunk. The exception to this rule is multi-trunk trees, which some may argue are really very large shrubs.

Glossary : pH

pH, means the potential of Hydrogen, is the measure of alkalinity or acidity. In horticulture, pH refers to the pH of soil. The scale measures from 0, most acid, to 14, most alkaline. Seven is neutral. Most plants prefer a range between 5.5 and about 6.7, an acid range, but there are plenty of other plants that like soil more alkaline, or above 7. A pH of 7 is where the plant can most easily absorb the most nutrients in the soil. Some plants prefer more or less of certain nutrients, and therefore do better at a certain pH.

Glossary : Large Tree

A tree is considered large when it is over 30 feet tall.