Oil painters know that there is a critical point in the evolution of a painting where it has reached its potential and any more paint will bring negative returns, ultimately destroying it. When we read the story "Arboretum branches out" (Dec. 25), our hearts sank and our mutual response was: They are now beginning to put on too much paint, risking the very dimensions that have made the Minnesota Landscape Arboretum "best of class" as far as we are concerned.With admiration and confidence, we have watched former administrations clearly understand that when you add on to a natural setting, as in recent arboretum shows such as "Big Bugs," there is a critical point when these shows overwhelm the context in which they exist. Until now, we have never seen administrators go over this critical point, and we had been confident that it would not happen.

Now we read that this "branching out" is to appeal to the market, which then, by definition, will take the arboretum in a direction that's in the best interests of numbers and finance. That's a sad commentary and a betrayal to those pioneers right up to the last administration who made changes, such as the new visitor's center, without compromising the naturalness of the setting, which always seemed to come first.

Large installations such as an "outdoor performance center" interrupt and stand between the experience of the visitor with the beauty of the natural setting, not to mention the risk of overtaxing amenities such as parking. It is known that migrating native people have a practice of stopping in order that their souls might catch up with their bodies. We live in a world of speed, production, materialism, computers, traffic, etc., where we too often leave our souls behind and then seek diversions through things such as spectator sports.

The arboretum has always been friendly to the soul, a place unlike the rough-edged world in which we live and work. Now, it seems as though in the interest of marketing and possible aggrandizement, the arboretum is going to join the very world from which it has offered a healing escape. "While its new plans still focus on the arboretum's horticultural mission, they're also edgier and offer a broader entertainment value," the Dec. 25 story stated.

What's next? A Ferris wheel? Tailgating? Please stop and wisely -- judiciously -- evaluate major potential changes before too much paint is put on this treasure, a gift from many who have understood that less is sometimes more, with particular reference to natural settings.

CATHERINE AND Curt Paulsen, Chanhassen