Two tidbits from the March/April issue of "Fruit Gardener" (vol. 32,
no. 2; published by California Rare Fruit Growers,
http://www.crfg.org):

1. From the article, "The Annonaceous Fruits of Tropical America:
A Sweet Look at the Soursop," by Noel Ramos  (p. 12):

"The guanabana or soursop (Annona muricata) is among the largest-
fruited members of the annonaceous family. The fruits are green,
mostly oblong or heart-shaped with a prickly surface, generally
weighing from about 2 pounds to more than 10. An exceptionally large
25-pound fruit was reported by plant explorer David Fairchild while
travelling in Panama during the early part of this century."

Personal note:  I have eaten soursops in Florida, Hawaii, Costa Rica,
and
various locations in Southeast Asia. They are very nice indeed, though
the
texture might not please some folks. A 25-pound soursop would be
bigger
than most durians. There are a number of nice color photos of soursops
in
the magazine. (Despite the name, a good soursop is sweet, not sour.)

2. If you are interested in plant exploration, you might find it
of interest that "The Journals of Hipolito Ruiz" are finally
available translated into English. See the book review by Bob Vieth
on p. 24 for details.

Ruiz was a botanist sent by the King of Spain, to Peru and Chile
in 1777 to conduct a botanical survey. From the review:

"Over 2,000 plants are described. Of particular interest are the
uses that natives made of the plants. Examples included cures for
diseases - some evidently caused by spending time in the shade of
certain
trees* - and such substances as aphrodisiacs, dyes, poisons for darts,
extracts to ensure menstruation (a form of birth control?), purgatives
and laxatives...

The story told is one of contsant hardship from cold, rain, tropical
heat, insects, poisonous or otherwise hostile plants, treacherous
trails, repeated loss of collected materials due to calamities that
range from sinking boats to fires, and even death of the
participants."

* Note: One generally does not contract disease from being in the
shade
of trees, though disease vectors (insects, parasites) might be
correlated
with certain trees common in specific habitats. As well, there
is one tree so poisonous - the manchineel tree of tropical America -
that
raindrops falling off the tree onto a person can cause blisters and
poisoning.

Tom Billings
http://www.beyondveg.com