Evaluation of the site to develop the design is the first step in a tree planting program. Once you know the restraints of the site and the design requirements, plants can be selected and planting and maintenance specifications written to meet the site limitations. The following points should be considered during the site evaluation and design process:

• The USDA hardiness zones for Alabama are Zones 7 and 8. Hardiness is not as big a concern as tolerance to heat and low chilling hours or photoperiod required for proper bud set of some tree species.

• Is irrigation available?

• What is the light exposure, sun or shade?

• What is the soil nutrition analysis, especially pH, phosphorus and potassium? These nutrients are better adjusted according to the soil test prior to planting.

• What is the internal soil drainage? Test by digging a hole 18 inches deep and filling it with water. If water is gone in 1 to 2 hours, the soil is well drained; 12 to 24 hours, soil drainage is moderate; more than 24 hours, soil drainage is poor.

• What is the distance to the soil water table? Dig a hole 2 feet deep and wait 2 to 3 hours to see if water fills the hole. If water appears in the hole, there is a high water table. Is there a hard pan that limits drainage or is it a high water table?

• Is the soil texture clay, loam or sandy?

• Is the soil density compacted/hard or loose?

• Will your trees be planted in an open park setting, a sidewalk tree cut or a planting strip? What are the dimensions of the root zone space and volume of soil available for tree growth?

• Is there a swimming pool, septic tank, vegetable garden, annual planting bed within 50 feet of the planting area?

• What is the distance between the tree planting and any building?

• Are there underground or aboveground utilities or lights that need to be considered?

• Be sure trees are sited far enough back from an intersection or sidewalk and are limbed-up enough to prevent obstruction of views of passing motorists and allow for safe pedestrian traffic on sidewalks.

• Is there a budget for pruning and maintenance of the trees?

• Are there landscaping or tree ordinances that would affect selection and size of trees?

• What is an assessment of tree diversity in the area?

• Are the trees to be used for a screen, shade or a focal point?

• What trees currently exist in the planting area? What construction activities have recently gone on that might impact these trees? Are they healthy, desirable trees?

• What is the size, shape, texture, color, evergreen/deciduous requirements of the trees needed for the design?

• Are there storefronts, signs, traffic vision concerns or other views that may need to be considered in the selection of the trees?

Shade trees should:

• Have a strong, straight central leader with no lateral branches greater than 2/3s the caliper of the main leader.

• Have branches equally spaced around the central leader at least 6 inches apart. Each branch should have its own space.

• Have a uniform canopy in shape from all sides and free of large voids.

• Have trunks which are free from all cuts and scratches. There should be no more that 40% of the height which is clear of branches unless it is specified by the designer.

• Have proper pruning cuts that are not flush cuts but pruned to the collar.

• Have been root-pruned and irrigated during production for a better root system.

• Have root balls in B&B plantings which are of the appropriate size (see below) and they should be firm with no loose movement between the trunk and the root ball when the trunk is rotated.

• Have roots at the interface of the burlap and soil.

• Have container roots which fill the entire container without having any root greater than 1/5 the tree caliper and no large roots in the upper 3 inches of media encircling more than 1/3 of the root ball. If kinked roots are less than 1/3 of the root ball, they can be pruned.

• Have tree branches with good spacing and wide angles from the main trunk with no included bark.

• Be smaller rather than larger. Plant 1.5 to 3.5 inch caliper trees unless instant effect is desired and good soil conditions permit a large planting. Smaller trees establish better in poorly drained, low oxygen soils.

Standards for Various Container and Field Grown B&B Trees
The following tables, taken from the American and Florida Standards and Grades for Nursery Stock, offer a guide to the MINIMUM acceptable industry standards for root balls and container sizes for field and container grown trees. When selecting trees from the nursery, be sure that the nursery stock meets or exceeds these guidelines.

Once the proper tree has been selected to fit the site and the landscape design, proper planting and follow-up care are required for the success of the project. The following points should be considered during the planting process:

• Trees are transported to the site in a covered vehicle that prevetns wind and termperature extremes.

• Plants should be well watered prior to shipping and checked for moisture at arrival.

• On site plant material is maintained under shade and irrigated twice daily. Plants are healed-in if B&B material is used.

• Trees should be protected from extreme temperatures, freezing or extreme heat.

• Always handle tree by the root ball using straps or powered equipment and do not lift using branches or the trunk. The trunk should be wrapped during shipping and the planting process for protection.

• Inspect roots of container trees and remove any large roots that are circling over 1/3 of the root ball especially in the upper 2 to 3 inches of the root ball. Removing very large roots can result in excessive stress and possible death of the tree.

• The hole should be dug 2 to 3 times wider than the root ball to allow easy access by the roots into the surrounding soil and no deeper than the root ball.

• Rough-up or score sides of the hole to prevent glazing or compaction of planting hole and potential obstruction of lateral root growth.

• Most urban soils are compacted and poorly drained resulting in low oxygen for the roots. Plant the tree with the root ball top at least 1 to 3 inches above the soil line with the trunk flare/root flare and uppermost roots at least level with the backfill surrounding the tree.

• Soil removed from the hole makes the best backfill unless the whole planting area can be amended uniformly. There is no apparent benefit from root stimulants, water absorbing gels, mycorrhizae or fertilizer at planting. Planting site should be fertilized according to Soil Test recommendations for long term health of the tree.

• Gradually straighten the tree as backfill is added.

• Remove synthetic wraps, rope, twine from the tree and ball. Wire baskets should be removed when possible but research and practical application allows for removing at least the top 2 to 3 rungs of the basket. Although wire does not deteriorate, roots grow to encapsulate wire without apparent damage.

• Slice a shovel or spade around the backfill to settle the soil and remove air pockets. Break up heavy clay clods. Do not step firmly on the backfill which may cause excessive compaction.

• Irrigate with 10 to 20 gallons of water to the root ball and surrounding soil. Apply 2 to 3 inches of mulch to the edge of the root ball extending 6 to 8 feet from the tree. A thin layer of mulch (1/2 inch) can be applied to the root ball area for aesthetics. Do not pile much against the trunk of the tree.

• Only a thin layer of mulch and no soil should be on the top of the original root ball allowing the roots surrounding the root ball to be on the surface and water to penetrate into the root ball.

• Stake the tree if the planting is in a windy area or an area of high traffic. If the tree is leaning due to lack of taper or strength, tree selection was improper. Many trees with heavy root balls do not need staking.

Maintenance Requirements for Successful Tree Planting

• Trees provided with regular irrigation, 3 times per week, for the first 6 to 8 weeks during the growing season to stimulate greater root growth. Moisture should be monitored carefuly for the remainder of the year. Establishment period is about 6 months for each inch tree caliper (ex. 3” caliper = 18 month establishment period).

• Two to three gallons of water is required for each caliper inch of tree. Irrigation is applied to the root ball. If root ball is wet, do not irrigate.

• Pruning should have been done at the nursery. No pruning for the first year after planting. Pruning can inhibit root growth and establishment.

• Maintain 8’ mulch area surrounding tree and limit traffic to prevent compaction.

• No grass or weeds are allowed close to the trunk.

• Inspect planted trees to be sure they were not planted too deep and root flare is distinctly visible.

• Remember to remove all stakes and guying materials after first year.

• Pruning is required after year 2 to remove lower limbs to lift canopy and maintain central leader, limb spacing and arrangement of limbs on the central trunk. Proper pruning cuts are required (no flush cuts!).

• Trees respond to fertility after year one primarily to Nitrogen (N) at a rate of 3 to 5 pounds of N per 1000 ft². If phosphorus and potassium have been adjusted to a medium level or better, those nutrients should be sufficient.

• A split application of fertilizer in winter/spring (February/March) and again in mid June should result in maximum growth potential.

• Sandy soils can benefit from 3 applications for maximum growth using the same rate split into 3 applications in February, late April/early May, and late June/early July.

• Older trees, one application in February/March.

High to Medium High Wind Resistance
If volume of soil for root growth is limited, small to medium trees should be selected. Small to medium trees offer little damage potential and are better suited to small urban island planting sites. There are many other great trees for the landscape but these trees have been selected for their stability in hurricane areas.

Note: “P” indicates better for park setting with improved soil quality and volume.

Larger Urban Trees
In order to mature to their potential, large trees need room (soil volume) for their roots to expand. A good general rule is for every 1 inch caliper that you envision the tree’s mature growth, you need to provide a minimum of 2 feet for each inch on the side of a square root zone planting area. Example: If you envision a 12 inch caliper tree, the root zone required is 2 feet x 12 inches = 24 feet square or 576 square feet root zone area. Another general rule is you need 15 feet square planting area for a tree to realize its growth potential. Large trees resistant to high or medium winds include: