I am undertaking a big landscape job here on Puget Sound, and there are a
lot of young paper-birches with birch gall on each side of the property,
mostly twelve to eighteen foot little trees, each with at least a few
"knots" in the higher branches, some with a great many of these knots. I
have to make the decision whether or not to remove all these birches, & am
leaning toward replacing them with fruiting trees. But before I start
getting rid of two dozen young trees, I would welcome opinions from anyone
with experience with birch gall, since this is my first encounter that I
personally had to do anything about, & I'm not at all certain what's best.
Some questions:

Can the birch gall mites infect any other shrubs & trees other than birches?

The gall isn't apt to damage the longevity or general health of the tree,
but I gather it can make the leaves look pretty crappy. If some or all the
birches are left where they're at, will foliage look pretty decent even
with gall?

I also gather that miticides don't work very well even for the non-organic
gardeners who don't mind using them. I don't want to use such chemicals,
but wonder if there are any risks to just ignoring the presence of birch
gall mites?

Is the standard advice to remove & replace these trees to be taken seriously?

If I do remove these trees I want to do it now while the mites are dormant
& I have a better chance of burning every one of the little *******s. I'm
hoping they're not apt to attack the ornamental maples or fruit trees
since usually each gall is species-specific & no future birches will be
planted. If they are by & large harmless, though, I could view the two- &
three-inch knots in the branches as being themselves rather ornamental.

-paghat the ratgirl

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
Visit the Garden of Paghat the Ratgirl: http://www.paghat.com