There is no better reason for studying brambles than to simply find out how many distinct species are present in one’s local area or county. They also produce attractive flowers and lend themselves to photography and herbarium collection. Indeed it is essential to collect and press specimens in order to build up a reference collection which can then be checked by experts at a later date or used to compare with named species in herbaria and historical collections. See my detailed step by step guide to collecting and pressing brambles.
Studying brambles can make a pleasant diversion for the keen botanist after the spring and early summer bonanza of other flowering plants – they are at their best between about mid-June and the end of July in southern England, but the
season is variable (much dependent on weather during the previous winter) and is usually at least a month later in the north.
Finding brambles is not difficult! Brambles are competitive herbaceous plants that mostly prefer to grow in neutral to acidic but moderately fertile and deep soils, though some do grow in calcareous, strongly acidic, shallow or very poor soils. Most species need at least a reasonable amount of rainfall and soil moisture to thrive, and many do not tolerate full sun, so brambles are most at home in woodlands, hedgerows, scrubby heathlands and old commons. There are a few adventive species, which are non-native and which can be invasive in certain situations. The most successful of these is Rubus armeniacus. Many species are largely restricted to historical landscapes, such as ancient woodland and old heathland, and it is apparent that many have very narrow preferences in terms of microclimate. The fruits are dispersed mainly by small mammals and birds and can be carried hundreds of kilometres by migrant birds, resulting in the appearance of odd bushes well away from a species' core population. Isolated woodlands used by roosting birds are a good hunting ground for brambles, but towns and cities can also be productive.
Brambles are in the Rose family Rosaceae. In Britain they are divided into four sections, of which one, section Glandulosus, is represented by 11 series. An outline of these divisions and a summary of their distinguishing characters is given on the Rubus classification page. The only published identification keys to the species in Brambles of the British Isles by Edees & Newton (see below) have a few mistakes and are not really suitable for beginners, though it is certainly worth trying them out. The differences between the taxonomic groups are important to learn, but not essential to know to begin with – they will become clearer over time. A major problem with brambles is that some species do not fall clearly into any group and indeed, two of the series, the Micantes and Anisacanthi, are partly used to place species that do not fit elsewhere.
In the south of England there may be a bewildering number of species present in any one area, which can be a bit daunting for the beginner, but things are much easier in Scotland, where there are fewer species. To make a start it can be useful to look at your county flora to find out which are the more common and widespread species in your locality, then try to find and identify these. Contact your local BSBI vice-county recorder to find out if anyone records brambles in your area, and if so, see if they will take you on an excursion. The BSBI also arrange national meetings, which have been annual in recent years (there are two in 2016).
To learn more about brambles it is useful to obtain a copy of the Brambles of The British Isles by Edees & Newton (1988), which includes informative accounts of their history of collecting and study, geographic distribution in the British Isles and their life histories and ecology. This book is long out of print, but a CD version is available from Pisces Conservation. Updated distribution maps were shown in the BSBI’s Atlas of British and Irish Brambles (Newton & Randall 2004).
The Rubi of Great Britain and Ireland by W.R. Watson was originally published in 1958 and reprinted as a paperback edition by Cambridge Press in 2013. The descriptions are much more concise than Edees & Newton, but often include more useful identification characters. However, because Rubus nomenclature has changed so much since then, it is difficult to equate the names used with modern-day ones.
The Plant Crib (Rich & Jermy 1998) has a key to the taxonomic groups and useful advice on collecting and pressing specimens. It is also available here on the BSBI's web site. Staces's Rubus account in the New Flora of the British Isles, Third Edition (2010) has a succinct key to the main groups and introduced species and a plate showing sillhouttes of species with different types of leaf shape; however, the line drawings are very poor. The Hybrid Flora of the British Isles (Stace, Preston & Pearman 2015) gives a technical account of the genetics and reproduction of the Rubus aggregate.
A small booklet, Looking at Brambles, dealing mainly with East Anglian species was produced by Alec Bull, and is also worth reading (it was recently reprinted).