Hi Michael,
I'll try and answer some of your questions, although most of my
experience
is with apples and stone fruits.

m v wrote:

Hi,

I have a very old grapefruit tree with great tasting fruit. Really the
best grapefruit I have ever had. It is white, large, and very sweet.
I don't know the specific cultivar or rootstock. It is in S. Florida.
How can I find out?

Trees are best identified by their leaves and fruit. Try taking
samples
of these to your nearest horticultural experts.

The tree is 30-35 years old and looks like it is declining. There is
some bark damage around the trunk. It is about 25.' tall How can I
start a new tree with the same traits?

Grafting is the only sure way to preserve the character of the
original tree.


I have done a little research and see that seedlings can work (true to
type) but take a long time to fruit and may be not be hardy without
grafting them to rootstock.

Seedlings carry the characteristics of the previous generation, and
may
not produce the same fruit you are expecting. If that seedling came
from
a blossom that was pollinated from another tree, the probability of a
mismatch
goes up.

I also see that budding the original tree onto rootstock will produce
fruit much sooner (the bud remembers it's age). Will this produce a
tree that is allready old and may not live long? How long would an
old bud placed on a young root be expected to live?

The bud does not carry an 'age' gene with it. The important thing is
that
the bud is healthy and fresh enough to bind to the tree it is being
attached to.
Once the bud takes hold and grows, it should be just as good as one
coming from
a younger tree.

Any other methods I should consider?

A bud graft is where you attach the bud to an existing branch of a
tree. Other grafts
would involve attaching a piece of scion (a branch of your older tree)
to a root stock.
If you don't have another grapefruit tree to attach the buds, you will
have to get some
grapefruit rootstock graft some scion onto it.


Sherwin D.

Thanks in advance for any help,
Michael