Introduction

This fall on the way to the Northwest Bonsai Association meeting in Portland we visited the Wind River Arboretum located in the Gifford Pinchot National Forest in Carson Washington.

The arboretum was established in 1912 by the US Forest Service to determine the best trees to grow in the Northwest for timber and commercial purposes. The study planted trees and seed into the test fields and allowed them to grow untouched, more or less. The trees that grew the largest and best would be selected for tree farms and such projects.

Can your guess the results?

1. Broad leaved trees and hardwoods were unsuccessful.
2. 165 conifers were planted, and many trees looked like they would be more vigorous. In the long run they all failed to improve upon the growth of the native Douglas fir, western hemlock and true firs.
3. Tests of less than half a century can be deceptive. Some trees that were successful were killed after growing well for more than 40 years, but then succumbed after severe weather.
4. Even trees native to the Northwest USA brought to the range from the East of the Cascades failed. A few trees planted in ornamental lawn areas where they are watered in summer drought showed phenomenal growth. This area receives 90 inches of rain but there are long dry summers with drought typically lasting for 30 days that can stretch to 60 days.
5. Many pines did well for 40 years but one winter heavy snows smashed most of these trees, most of which did not recover. Native species were damaged as well but fared much better.
6. Species introduced from east of the Cascades failed from needle diseases. Higher humidity west of the cascades may have promoted these diseases.
7. In all 621 lots of seed and plants were tested.

Their conclusions

Our Doug fir, hemlock, lodge pole pine and noble fir have been introduced around the world and grow at better rates than the native trees of foreign lands. Our effort here, in the Northwest USA, has found no successful exotic. The worlds best conifers already grow here.

What are my conclusions and speculations?

1. Although growing trees in the ground without much care is not the same as growing trees in containers as bonsai, in the long term many trees that we are using for bonsai will fail. Either they will die or have some growth or insect problem that will make them unsuitable to long term bonsai culture.
2. In countries like Japan and China, with many years of bonsai tradition, they use relatively few trees for bonsai. These successful bonsai have been culled from many of their own native or regional materials. This may be telling us that the trees they use are the survivors in pots.
3. In the west we are now beginning the long process of determining which of our native species do well as bonsai. Some of the trees that we work with will be successful but likely many will fail. Excitement about new species and varieties of tree for bonsai may be overdone. Many of these will likely also fail the test of time.
4. Work done to trees like severe reductions, extensive jin and shari work may prove in the long run to be the ultimate demise of these trees. It may take 10 to 20 years but these "damages" may start a death spiral in the tree.
5. Our work with bonsai will take many years to determine which species will be long time survivors and whether our manipulations are detrimental. This does not mean we give up our bonsai efforts but realize that much of what we do now may not last for many years.