I frequently get asked questions about shade trees for planting in and around landscapes, recreational areas, and even natural areas. There are many from which to choose, way to many to start to mention in a brief news column, and each has many advantages and disadvantages. My personal opinion is that we sometimes search so hard that we overlook the most obvious choices.
Oaks have always been among my favorite of all the large trees, and who among us doesn’t have some recollection of the stately old oak tree back at the old home place. Just remember that if an oak tree is your selection, it’s not just an investment in purchasing the tree but rather an investment in time. Oak trees do not grow and make shade in one or two years or in ten years for that matter.
Although they can be planted all the way through wintertime, the best time to plant oak trees (and most other woody ornamental tree for that matter) is in the fall. Fall planting will allow the tree time to develop a root system and get off to a much better start come spring. Your oak tree should also be planted in full sun with plenty of space in which to grow. Remember the small seedling you set out now can someday reach one hundred feet or more. If shading your house is what you have in mind, try setting the tree on the south or west side and give it a minimum of twenty-five feet from your house to allow for root growth.
When you plant your oak tree make sure you begin with a hole that is three to five times as wide as the root ball (note the hole should be wider NOT deeper than the root ball). Place the root ball on firm ground in the center of the hole so that the top of the root ball is even with the top of the ground. Backfill the hole with soil and water slowly and deeply. Complete your planting by adding two or three inches of mulch. Plain simple pine straw will work fine! You may want to extend the mulched area two or three feet around the tree to cut down on weed competition and to prevent you from getting against it with a mower or string trimmer. Some purchased trees come wrapped in burlap. If this is the case remove any string or wires attached to the burlap; however, it will be fine to leave the burlap itself around the root ball. Never allow the burlap to extend above the surface of the soil because it will wick moisture away from your tree.
There are many different selections of oaks, and not all of them are designed for all locations. Here are just a few of my personal favorites.
If you are lucky enough to have a lower lying area that holds moisture but doesn’t flood, overcup oak is a great choice. It will reach a top height of up to one hundred feet but branches about twenty feet above ground to form a wonderfully symmetrical canopy that makes a very attractive landscape addition. Water oak or willow oak are good choices for damper areas. Water oaks attain heights of around eighty feet or so and make great shade trees.
Willow oak is a great selection for the wettest areas of your property. In fact willow oak can stand wetter areas than just about any other oak species. It gets its name from its leaves that are shaped more like a willow tree than an oak tree. It is a relatively narrow tree rarely ever exceeding four feet in diameter with a more open and conical shaped canopy.
If you are looking for a fast growing oak tree (relatively speaking of course) shumard oak is just that. It makes a large very straight shade tree. The only problem with shumard oak is that it frequently holds it’s dead leaves through the winter and will drop them in the spring when the new growth begins.
For areas that are more upland and tend to be drier, either of our two most common oak trees will fit the bill. Both northern red oak and southern red oak will not grow well in places that tend to hold water for extended periods of time. Scarlet oak is another smaller growing oak that prefers dryer sandier locations. Scarlet oaks sure will not disappoint you with their fall color which is a deep scarlet red color (hence its name).
Chestnut oak is an interesting selection that will fit into most any landscape with its smaller growth habit and unique reddish brown almost black bark. The acorns produced by chestnut oak are quite large in size but none the less these trees are absolutely beautiful planted in groupings in natural areas.
One of my personal favorites not necessarily for its beauty or its large statue is the post oak. Historically post oak was used for making railroad ties and farm implements and is considered by many as a “scrub oak”. It is small compared to other oaks reaching only sixty feet or so and has stout forked branches. Its foliage is a distinctive cross shape. Post oaks prefer a dry sandy upland area in which to grow. Again, this is not my first choice for a yard tree but will look great on dry sandy hillsides.
Finally, no mention of oak trees would be complete without what most people consider the “Cadillac” of oak trees, the stately white oak. Early pioneers planted white oaks to mark home and plantation sites and it certainly offers much in historical value. White oak is considered by many to be our single greatest native tree. It is widely adaptive to many sites and has attractive whitish gray scaly bark. Planting white oaks is definitely an investment in the future as it is also one of our slowest growing trees.
These are just a few of our more common oaks (and there are many others as well) that are worth considering if you are thinking about adding some large trees to your property or else considering future shade producing trees. While we are on that line of thought, I will add one additional tree (even though it is not an oak) that I think far too few yards and landscapes in and around our area utilize. Black gum or “black Tupelo” (not to be confused with our very common sweetgum that produces those sticky seed pods that everyone complains about) is an outstanding native tree with a moderate mature size (a little slow on growth rate) but has relatively few pest problems and outstanding fall color.
After you plant your oak trees provide them with at least one inch of water per week until they are established and fertilize them with a complete fertilizer such as 12-6-6 or 8-8-8 during the early spring. A fall application of low nitrogen fertilizer such as 0-20-20 or 5-10-10 will help to winterize your trees.
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