BOOK REVIEW

A guide to a vanishing flora

Brian W. van Wilgen

Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa Email: bvanwilgen@sun.ac.za

Book Title: Field guide to renosterveld of the Overberg
Authors: Odette Curtis-Scott, Mike Goulding, Nick Helme, Rhoda McMaster, Sean Privett, Charles Stirton
ISBN: 9781775845805 (epub, 488 pp)
Publisher: Struik Nature, Cape Town; ZAR290
Published: 2020

Renosterveld is a highly endangered vegetation type that once covered over 2 million hectares within the Cape Floristic Region. Today, the estimated 18 000 remaining patches are widely scattered across the landscape, collectively covering less than 4% of the original extent of this once-expansive veld type. Renosterveld differs from the neighbouring and better-known fynbos in that it occurs on nutrient-rich soils derived from shale, as opposed to the nutrient-poor sandstone soils that support fynbos. Fynbos is best known for its tall proteas and showy ericas, as well as reed-like restios. Renosterveld, on the other hand, is more grassy and characterised by shrubs of low to medium height. In the past, and unlike fynbos, renosterveld supported an abundance of large grazing mammals and their accompanying predators. This began to change around 2000 years ago when the Khoekhoen arrived with domesticated livestock whose more selective feeding habits would have differed from those of wildlife, thus impacting on the flora. Large wild mammals were virtually exterminated when European settlers arrived with modern firearms some 300 years ago, and domestic livestock became the dominant grazers. The fate of the renosterveld was finally sealed after World War II, when mechanised farming allowed large tracts of land to be converted to crops such as wheat and canola. Whether the original renosterveld was a shrubby grassland or a grassy shrubland is a topic that ecologists debate today, as the changing grazing pressures and human-influenced fire regimes would have affected the proportional contribution of these two important components of the vegetation. Better understanding of this issue would be important for managing this vegetation type correctly, and this book provides some insights into these intriguing questions. Nonetheless, forming an acceptably robust grasp of the functioning and dynamics of such a fractured ecosystem is akin to visualising the image of a 100-piece jigsaw puzzle from four remaining pieces.

This book is, however, not primarily intended as an ecological treatment. Rather, it provides a guide to almost 1000 plant species that occur in the renosterveld of the Overberg, a region that stretches over 300 km between Caledon and Mossel Bay, south of the Riviersonderend and Langeberg mountains. Many of these plant species are found nowhere else on earth, and many are classed as Endangered, or Critically Endangered, in South Africa's Red List of Plants. The concise documentation of such a large, rich and often unique flora is a notable achievement. Each species is described in adequate detail, and where appropriate its IUCN 'Red List' status is noted. A key feature that makes this book so attractive is the remarkably high quality of the photographs of each plant. Modern digital photography has resulted in vast improvements that will allow readers to identify species much more easily. Over 70% of the book (350 pages) is devoted to plant species, but an additional 50 pages also cover some of the more interesting birds, mammals, reptiles, fish and invertebrates of the region. While these sections are not comprehensive, they will certainly be useful for visitors who are unfamiliar with the area's fauna.

The intended readership would presumably include nature lovers and plant enthusiasts, as well as tourists. However, renosterveld is not readily accessible to members of the public, as 99% of the remaining land is in private ownership, presenting a challenge to potential users of this book. The authors devote part of this book to landowners who are taking positive steps towards conserving renosterveld patches on their land, and they describe the initiatives of 12 prominent farmers who are labelled 'conservation heroes'. The book also introduces the 500-ha Haarwegskloof Renosterveld Reserve, which is home to the Overberg Renosterveld Conservation Trust and a first-ever Renosterveld Visitor and Research Centre. The reader is informed that 'all nature lovers are welcome', and although no further details are given, they are available on the Internet.

This book is the first to be devoted to the flora, fauna, ecology and management of the renosterveld, and as such it is a major step forward. It should be of considerable interest to farmers and other landowners of the area, but it will also raise awareness of the conservation importance of renosterveld among town dwellers and tourists and will be a useful resource for students of botany and ecology. Odette Curtis-Scott and her co-authors are to be congratulated on producing such a handy and attractive guide.

Published: 29 March 2021