As an amateur horticulturist interested in tropical plant propagation, I WOULD give Robert Riffle's book a five star rating for the amount of helpful and user-friendly information and photographs it contains within its pages. As a conservation biologist working on the island of Maui, however, I am compelled to give this book the lowest possible rating (one star) to draw attention to the fact that many of the plants Mr. Riffle advocates are terrible weeds in the native ecosystems of Hawaii and threaten to crowd out and overwhelm many of the already rare and endangered species found in the islands' ever-shrinking native habitats. It's bad enough that he recommends such beautiful, if incredibly aggressive and quick growing species such as Strawberry guava (Psidium cattleianum), kahili ginger (Hedychium gardnerianum) and banana poka (Passiflora mollissima). These notorious plants have already invaded many of the Hawaiian islands', and therefore the United States', last remaining rainforests, and have contributed to the loss of habitat and biodiversity in a place which makes up less than 0.2 percent of the total land mass of the U.S., but contains 75 percent of the recorded plant and bird extinctions. What is almost unforgivable is his treatment of the genus Miconia, of which he makes the unwitting proclamation "no other tropical genus warrants more attention than this one." For his information, the genus Miconia, and in particular, the velvet tree Miconia calvescens has been the focus of a massive eradication campaign in both the Hawaiian Islands and the Society Islands (Tahiti etc.). This quick growing tree, which was planted in a botanical garden on the island of Tahiti in 1937, has, in the past 50 years, come to dominate over 70 percent of Tahiti's native forests, placing 40-50 of the unique tropical Tahitian plants on the brink of extinction. In the Hawaiian islands, where Miconia was also introduced as an ornamental in 1961, a statewide effort, in which almost $1 million has already been spent, is attempting to prevent a similar situation from occurring. In addition, all 1000 members of the genus Miconia have been listed as noxious weeds by the Hawaii Department of Agriculture. That is why I was amazed to read such statements as "it is almost unbelievable that more of these beauties have not been exploited for gardeners in frost-free regions." It is almost unbelievable to me that, despite all of the attention and effort that has gone into protecting the world's rare tropical ecosystems, that nothing is mentioned in the book about the potential for certain plants such as Miconia to become aggressive invaders when grown outside of their native ranges. If Mr. Riffle loves tropical plants as much as is evident from reading the pages of his beautiful but misguided book, he will make an effort in the future to educate both himself and his readers on these types of conservation issues to ensure that all of the rare and unique tropical plants of the world, not just the ones he finds attractive, are still around for future generations to enjoy.
