blooming flowers climber in tree to prune beneficial mushrooms close up of lady bug on leaf japanese maple being pruned
Current Issue - Spring/Summer 2013

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The Arbor Advisor
> Heritage and Favorite Trees
> The Arbor Cars
> When to Prune?
> Ascending the Giants
> Featured Tree: Japanese Stewartia

The Arbor Car

The first thing Certified Arborist Phil Wich noticed about the new bio-diesel fueled Volkswagen Jetta he drives when consulting with Collier customers was that he wasn’t stopping twice weekly to fill up the 25 gallon tank of the large pickup he used formerly.

Lyle Feilmeier Consulting Arborist Phil Wich and his 40 mpg bio-diesel fueled “Arbor Car”.

Wich’s car is one of three “Arbor Cars” recently purchased for the company’s consulting arborists by the company President Terrill Collier to highlight the firm’s commitment to sustainable practices. The fuel efficient Jetta uses about 14 gallons of bio-diesel weekly and gets 40 mpg.

Said Terrill: “This was a natural move. We’re part of the ‘green’ industry. As it says on the side of our new cars – ‘environmentally friendly since 1937’.” The Arbor Cars are just one of many examples of our sustainable practices and commitment to protecting the urban forest. We are national leaders in Integrated Pest Management techniques that emphasize the use of environmentally friendly products and sustainable practices in protecting landscape plants from harmful insects and diseases.

Keep an eye out for Collier’s new bio-fueled fleet. They have plenty of pep and “they’re just plain fun to drive,” adds Wich.

Ascending the Giants

Many hobbies are somehow derived from a person’s occupation — Brian French and Will Koomjian’s endeavor has proven to be no different.

As professional arborists at Collier Arbor Care, Brian and Will spend their weekends climbing champion trees in the Northwest. They climb to document the size and ecosystems of these ancient trees during an on going expedition called “Ascending the Giants”.

Sequoia Pitch Moth Mass Brian belays Will at 335 feet to the top of the tallest Douglas fir on Earth.

Reflecting on their involvement with Ascending the Giants, Brian and Will concur that, “one of our goals is to foster the relationship between trees and people. With Ascending the Giants we hope to achieve this by giving a unique perspective that few people on earth experience — to see the tree from hundreds of feet off the ground”.

For more information on this organization and to see more inspiring photos of the climbs, visit

Image of boy hugging tree with dog looking on
Who cares for your loved ones?

Heritage and Favorite Trees

What is your favorite tree on your property? Is it large, historic, or planted by your grandfather? Or is it just beautiful, perhaps your favorite species of tree? You may call it a heritage tree, historic, signature, veteran, ancient or simply one that you love. Whatever you call it, the tree remains a prized treasure, one that you want to pass on to the next generation.

These special trees require a sustainable management plan that will help assure they live on for successive generations. Collier Arbor Care arborists are experts in maintaining these special trees. Many tree species such as Douglas fir, Oregon white oak, and ponderosa pines found in our area can live for 300 years or more.

We care for the Northwest’s oldest apple, The Old Apple Tree planted at Fort Vancouver in 1830. We also care for the Signature oak (pictured below) estimated to be over 500 years old and one of the largest of its species growing at the Oregon Garden.

Old mature trees have special requirements that are quite different from young trees and other short lived landscape plants. Collier consulting and certified arborists will help design sustainable management plans to care and nurture your trees for generations to come.

The following are key components in a mature tree management plan:

  • Tree inspection on an annual basis can discover changes in health condition before the problem becomes too serious. Inspections can help detect hazard conditions that may threaten people, property or the long term health of the tree.
  • Soil management includes proper nutrition and fertilization, improving clay soils, encouraging beneficial soil microorganisms, and watering to maintain healthy long term root growth.
  • Mulching reduces environmental stress by providing a forest like environment for a stable healthy root environment.
  • Pruning to improve branch structure, enhance vigor or maintain safety.
  • Insect and Disease Prevention — Using a plant Health Care Program we can prevent harmful insects, diseases and decays from shortening the life span of your tree.
Call on one of our consulting arborists to develop a management plan for your favorite tree that will sustain it for generations to come.

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Japanese Maple being pruned.
Prune to improve health, aesthetic appeal, control size and reduce hazards.

When to Prune?

By Terrill Collier

While teaching a Master Gardener class this year, I was asked; when is the best time to prune? My reply is “when your saw is sharp!” This may seem a little glib but most people including many pruning experts put too much emphasis on timing and not enough on the how of proper pruning. People are very concerned about when to prune with respect to blooming. If you use selective thinning cuts your plant or tree will still bloom normally and profusely, only minus a few of the blooms that were pruned. You only get into trouble when you top trees or use heading or shearing cuts on blooming plants.

Pruning the dead wood or hazardous branches (crown cleaning) out of plants and trees can be done any time of year. You cannot hurt a plant by pruning out the deadwood. Selective thinning (crown thinning) if done in moderate amounts (less than 20% of the crown) can be done any time of year. The following are some generalities and guidelines on when to prune for specific situations.

Dormant vs. Summer Pruning: No matter when you prune, pruning always leaves your plant smaller or thinner. There is a tendency that dormant season pruning is more invigorating and summer time pruning is more dwarfing. If you are trying to renovate an overgrown laurel hedge then prune right before bud break and the new growth will quickly cover the pruning cuts. If your goal is to contain your plant size then summer pruning is best. An example is the annual shearing of arborvitae hedges after the spring flush of growth to maintain size and shape.

Bloom Time Pruning: Bloom time pruning is only a consideration if you are doing radical size reduction or improper pruning. However you can’t go wrong by considering the following guidelines. Prune spring bloomers in the summer and summer bloomers in the spring. Rhododendrons are a good example of spring bloomers. Spring flowering shrubs set their buds in the summer and the buds go through the winter ready to bloom in the spring. So wait until it blooms then prune in the summer. Summer blooming shrubs start growing in the spring, then set buds and flower in the summer so it flowers on the current year’s growth. An example of summer bloomers are roses which we can prune in the early spring then they will bloom like crazy later in the year.

Large Tree Pruning: Most shade and ornamental trees can be thinned and dead wooded any time. However sometimes pruning can allow a tree to become more susceptible to certain insects or diseases. An example is to prune elms in the dormant season to reduce the chance of Dutch elm disease transmission by the elm bark beetle. Some trees like maple, birch and walnut when pruned in the early spring will bleed sap. While a tree cannot bleed to death, the sap flow can be annoying especially if it drips on cars or paved surfaces.

Fruit Tree Pruning: Traditionally fruit trees are pruned in the dormant season when there is no fruit on them. However if your goal is size containment then it is desirable to prune in the summer. Also summer thinning of fruit trees allows for fewer, but higher quality, larger fruit to form.

Your pruning job is just too big to tackle? The hedge is too tall and wide for you to trim? You tremble with fear at the thought of your spouse using power equipment? Call the professionals at Collier Arbor Care. Our certified Arborists will efficiently tackle your biggest job and turn those out of control plants into living works of art.

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Tamukeyama The flowers are white and 2 inches wide with a central mass of orange anthers. The bark exfoliates in striking patterns of gray, orange and reddish brown.

Featured Tree: Japanese Stewartia (Stewartia psuedocamellia)

Once seen the Japanese Stewartia (Stewartia psuedocamellia) should win a place in the discerning gardener’s heart and landscape. This slow growing tree has outstanding four season appeal. The flowers and fall color are exemplary but the bark exfoliates in striking patterns of gray, orange and reddish brown and is a real show stopper especially in winter.

The Stewartia grows best in moist organic soils. It is a woodland tree that grows best in partial shade because its leaves can scorch in full hot sun. It eventually reaches a height of 30-40 feet tall with a pyramidal growth habit.

The flowers are white and two inches wide with a central mass of orange anthers. They open in July and look very much like camellia flowers hence the scientific name.

The Japanese Stewartia is an excellent specimen or focal point tree. Several trees in a grove-like setting look terrific especially planted as a foreground specimen against a backdrop of larger, darker leafed trees.

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