You are doing what you can do, but there really is no saving a tree that is having this many problems.
The report from the arborist who visited you home was a little disheartening, but at least she had a plan for saving the two trees that were still healthy, and she also had advice about removing the tree that was no longer salvageable.
Even though you tried to correct some of the root problems that your trees were experiencing two years ago, those efforts were not enough to improve the stability of the nine year old trees that separate your property from the street. As the arborist explained, in fact, it was that these street trees were planted in the first place that has lead to these problems. Without enough room for the roots to grow because of the surrounding concrete sidewalk and street, the trees often have fairly short lives.
You were actually in the process of getting advice on some landscape design when you realized that you really needed to consult an arborist as well. You knew that going ahead with any landscape design would be rather foolish until you addressed the problem with the three trees in your yard that were not looking very good. Professional landscapers can often offer advice on both plants and trees, but many times it simply makes more sense to consult an arborist as well.
For instance, if you have an ash tree that you are not planning on treating any longer, it seems like a pretty good time to make sure that the tree is removed so that it does not fall and become an even bigger problem. The biggest issues that landscape designers and an arborist both focus on are planting and environments. Deciduous trees, for example, do best when they are planted in the fall many areas of the country. What a home owner sees above the ground means that there is that much and more under the ground, and even a tree that may have seemed good for years can suffer substantially when a major weather event occurs.
Even after you have selected the best plants and the best trees and planted them at the right time, for instance, many many plants and trees require fairly constant attention. For instance, the goal of pruning is that you have enough clearance to walk around it. Any branch that limits this is an indicator that pruning is needed. Getting the canopy of a tree up adds to not only the health of the tree, but it also makes for a far more attractive yard. By pruning the maple and pruning the linden in your front yard, for instance, the arborist indicated that within a few years you would actually see an increased amount of shade on your property.
Beautiful Landscaping Requires Attention to Detail During Plant and Tree Selection
Consulting a professional landscape designer is one way that home and business owners can help protect the investments that they make. Especially when it comes to selecting and purchasing expensive trees and some larger plants, getting advice from a local expert can help you make the best decisions. Consider these other facts and figures about the role that trees and landscaping play in the value of a home or business:

• Trees can reduce an unshaded home?s summer air-conditioning costs by as much as 15% to 50%.
• Energy-efficient landscaping can save up to 30% on home heating bills, according to the US Department of Energy.
• Planting a row of dense trees can block up to 95% of sunlight and 75% of the sun’s heat.
• Landscaping can bring a recovery value of 100% to 200% at selling time, according to Money Magazine.
• Homes with “excellent” landscaping can generate a sale price nearly 6% to 7% higher than equivalent houses with only “good” landscaping. according to a study by Clemson University.

Trees and landscaping not only add beauty to a home or business. They can also add value to a property and even, at times, decrease utility costs. Are you ready to upgrade the landscaping at your home? Often, it is in your best interest to consult with a professional whenever you are making these decisions.