Many of us enjoy a walk through a wood in autumn. We take pleasure in the weakening rays of the sun and the autumnal scent of freshly fallen leaves. Whilst gazing at the hazy beauty of a fog-laden wood, all too often we trip up. Our feet have been snagged by a bramble stem. After some cursing and attempting to remove the offending briar from the path, we return home. For most of us, that is as far as our relationship with brambles goes. Some of us may enjoy blackberry and apple pie or blackberry jam, but that is all.

I am rather fond of brambles, but not as fond of them as batologists, of whom I shall return to later. Why the fondness? First, being a botanist, I’m rather keen on all plants, I can not think of a wild plant that I unable to admire. Although, it is fair to say that some, more heavily hybridised varieties of garden plant leave me a little cold. Back to brambles, their role in the ecology of our countryside is probably one of the more important ones of our wild plants. They provide nectar and pollen for a myriad of invertebrates when in flower. Their roots, stems and foliage are food for many more, as well as various mammals such as deer. Wild boar are also rather fond of them, the young shoots, rhizomes and roots are a tasty snack; their penetrating snouts churn up the soil and create new habitat. Brambles even host a range of specialist fungi that call them home, one of the more common and easily seem is the violet bramble rust (Phragmidium violaceum). Violet bramble rust is an obligate biotroph which means that it is unable to complete its rather complex life history without the presence of brambles. It can be seen as reddish-purple blotches on bramble leaves though summer until the leaves fall in autumn. Of course, we most value brambles for their fruit and this is also true for wildlife. The fruit of these plants are an invaluable food source for many species in late summer.

However, the main reason I am rather fond of brambles is because I very often encounter them at crime scenes. I am happy to see them not only because I value them for their aesthetic or ecological value but because they are often of assistance to me in my role as a forensic botanist. Some types of brambles are common in places where people abound and where crimes are committed. This is not because they have an affinity for humanity but because humans tend to increase the nutrient load of soil and water courses (mainly through agriculture, sewage and transport). Brambles thrive in these conditions, they are greedy feeders and the extra nutrients we supply are to their liking. So, why are brambles of use when investigating crimes scenes? Basically, they are vegetable calendars (all plants are for that matter, we just need to learn how to understand them), they can be of assistance in estimating how long a person’s remains have been at the location they’re in. Quite often when a dead person is first found, the police will often not know who the person is. To establish their identity, the police will pursue various avenues of investigation. One important question will be ‘How long has this person been here?’. In some cases, brambles (and other plants too) may help resolve that question. Despite appearing chaotic and messy to us, a bramble ‘thicket’ is not disordered, it is an elegantly structured and choreographed structure that enables the bramble plant to maximise its potential within its environment.

To understand how brambles grow it helps to understand what other plants they are related to. Brambles are members of the rose family (Rosaceae). The rose family is a fairly large one, there are nearly 5,000 species (for comparison, there are about 28,000 types of wild orchid). Members of the family include, not surprisingly, the rose (Rosa) as well as plums and cherries (Prunus), apples (Malus), hawthorns (Crataegus) and strawberries (Fragaria). In many respects, brambles are most like strawberries. Both plants have a similar fruit structure but more importantly, aspects of their growth are comparable too. Strawberry plants have a short, stout rootstock that produce long, thin trailing stems (runners) from which new plants develop. Brambles, and their close relative raspberry (Rubus idaeus), have a variation on this body-plan. Every spring, each plant sends up one or more fresh vegetative growths (called ‘canes’ in gardening), their role is to increase the physical territory that the plant occupies and outcompete other plants. In the case of brambles, the growing tips of these stem arch and when the tips meet the ground they produce fresh roots and a new plant. This is why brambles are so good at tripping us up, they’re often rooted at both ends – creating a natural trip-wire! The following year the same stem changes its function, it produces shorter side-shoots which flower and then bear fruit. During the summer, when the plant is flowering, further vegetative shoots arise from the ground and grow through and over the flowering stems. Over a period of years, the plant steadily gets larger as the fresh stems ‘overtop’ the older ones (which gradually weaken and die). Thus, for all their chaotic demeanour to us, brambles are very ‘organised’ plants with an effective strategy for surviving in our hedgerows, woodlands and the nutrient rich corners of our habitations where many crimes are committed.

The ability of brambles to gradually encapsulate territory is of value to me as a forensic botanist. When a dead person is found in places where brambles abound, they are usually found on the surface (often referred to as a deposition scene) or purposefully buried (a grave). Depositions may be due to accidental death, natural death, suicide or by a third party transporting the person to that location. Not surprisingly, graves always involve third parties! Either way, once a deceased person is in the environment, plants and animals respond to and accommodate the person’s presence. If a person’s remains are by a bramble plant, they will soon be covered by the plant’s growth, they become encapsulated until discovered. On discovery, it is my role to use the tell-tail signs in the plants structure to estimate how long the person has been where they are. I’m not going to reveal quite how I do this, I need to retain some of my ‘trade secrets’!

I have revealed how brambles can help fight crime. But what of batology? Brambles, alongside some other members of the rose family, such as the whitebeams (Sorbus) have a rather curious way of reproducing. They don’t have sex. Or to be honest, most of them don’t have sex. Many bramble species reproduce by apomixis (a rather handy Scrabble word), this results in the formation of a seed without the necessity for fertilisation. Apomixis is a complex phenomenon that is fairly widespread in flowering plants. One of its consequences is that these asexual brambles are effectively vegetative clones, another is that they are often very restricted in their range and extremely rare. The Trelleck bramble (Rubus trelleckensis) is restricted to Beacon Hill in Monmouthshire, Wales and may be vulnerable to extinction. It is not alone in this regard, many of the 300 or more recognised micro-species of Rubus fruticosus agg. (the collective term for this group of brambles) found in Britain and Ireland are similarly scarce. The complexity and diversity of brambles (hence the term ‘micro-species) is such that that relatively few botanist amongst us are brave enough to embrace them, those who do are known as batologists, which is derived from the ancient Greek βάτον (báton) for blackberry. Being a batologist takes time, patience and iron-clad fingertips. During my time at the Natural History Museum in London I had the honour becoming acquainted with the king of batology, David Ellis Allen. Not only is he a man of vast knowledge on brambles but his erudition in natural history and the history of our nation’s botany collections is remarkable.

At this point, I am hoping you may feel a warm glow when thinking of these plants. Sadly, all is not rosy. All too often, ecological damage is one of the consequences of humanity’s activities on this planet. In many cases, this damage is caused by non-native invasive species. Due to their tasty fruit, we have taken our brambles from their homelands and transported them all over the world. For many places, such as New Zealand and Hawaii the consequences have been disastrous. Many of Hawaii’s incredibly endangered plants are under threat due to competition with non-native brambles and the damage caused by the feral pigs that forage on them. Luckily, in some cases control measures have been found. The previously mentioned violet bramble rust fungus has been introduced to areas such as New Zealand where it is used as a biocontrol agent against invasive brambles. The fungus is so specialised and specific in its requirements that it is considered extremely unlikely that it will move to an alternative host.

The humble bramble is so much more than an annoying trip-wire. Embrace it’s wonder next time you fall to the ground in your local wood.