Mark A. Spencer - Murder Most Florid: Inside the Mind of a Forensic Botanist

This book is dedicated to the plants and the dead.

Contents

Sitting at my desk, my eyeballs are gasping for colour and sustenance. The open-plan office is very grey and devoid of natural light. Im rather bored and dont feel particularly engaged with my work today, which is unusual because I have an amazing job. I am the curator of the British and Irish herbarium at the Natural History Museum in London. An herbarium is a collection of dried plants. Its the sort of job that botanists would clamber over the flailing limbs of their competitors to get to. Nevertheless, Im bored. Its just one of those days.

The phone rings and I pick it up expecting to speak to a colleague. But its not a colleague: the voice on the other end of the line is a crime-scene investigator. They ask if I am available to assist them with a potential murder enquiry. The very heavily decayed remains of a man have been found by the edge of a river. He has been identified and is believed to be estranged from his family. There are concerns that he may have been killed by a relative, but it is also known that his mental health was poor, so suicide cant be ruled out. When discovered, the mans body was partially covered by vegetation and the crime-scene investigator would like to know if I can provide an estimate of how old the plants are. They hope this information will help establish how long his remains have been at the location.

As I ask some questions about the vegetation surrounding the body, it soon becomes clear the investigator knows almost nothing about plants. Equally, I know very little about crime scenes. I cant draw upon television crime dramas for knowledge as Ive never been a fan, unless they have Christopher Meloni in them, but thats another matter. The investigator offers to send me some images from the deposition scene and sensing Im green, she warns me that the images are very graphic. I accept. At least they wont be grey.

She was right, the images are graphic. As the office is open plan, I take care to open the file so that colleagues cannot see what Im looking at. Luckily, the desk dividers are high and Im in the darkest corner of the room. No doubt my colleagues can hear my exclamation, but they take no notice; theyre used to my intemperate outbursts. The images are of the deposition scene, where the mans body was found. There is lush vegetation along a riverbank, and it looks quite idyllic, except for the partially submerged shopping trolley and the mans very heavily decayed body. He is partially clothed, but his clothing can barely be discerned because it is discoloured by his putrefied remains. His ribcage, spinal column, arms and partially de-fleshed skull are clearly visible. His teeth appear bared. They are not his lips are no longer there, as they have been consumed by a diversity of organisms feeding on his remains. The nature of the decay is such that what remains of him is either dark charcoal grey or ash coloured and contrasts strongly with the late summer green tones of the vegetation surrounding him. I take in the images and await my reaction; will I be able to withstand this? I feel fine, which is a relief.

I call the crime-scene investigator back, confirming that I can assist and make my arrangements to travel to the deposition scene. Before I leave, I go upstairs to visit colleagues; they are both forensic entomologists. The Natural History Museum is well known for its expertise in dinosaurs, but behind the closed doors are many other specialists who are world experts in their own fields. One large group of researchers and curators are the entomologists. They look after and study the museums vast collection of insects. My colleagues use information collected from insects to estimate how long a person has been dead; this estimate is known as the postmortem interval. I need their advice and in return they have a favour to ask. They need me to collect insect larvae from the body and the ground nearby. They explain to me how I need to collect the specimens and how they should be stored. Am I happy to do that? I say yes and they give me some personal protective clothing as I have none. One of them also gives me a little pep-talk; she is very experienced when it comes to working with the dead and has even worked at the body farm in Tennessee, a famous outdoor research facility where the donated bodies of the dead are studied in scenarios emulating murder scenes or disasters.

On my way to the scene, I divert to a chemist and buy some surgical grade soap. Im not particularly obsessive about hygiene but Im starting to feel some anxiety about what Im about to confront. Its a long train journey and I attempt to brace myself for what Im soon to experience.

On arrival, I make my way to the local police station to meet the police officer in charge of the case, as well as the forensic scientist appointed to oversee my work. The officer explains to me that since my phone conversation the mans remains have been removed. We then proceed to where the body was found. The area is a typical light-industrial corner of a small town on the edge of the Pennines. Behind the single-storey warehouses and lockups, there is a small river edged with surviving fragments of the pre-industrial landscape. Most of the dominant plants are native trees and shrubs but there is also an abundance of invasive non-native Japanese knotweed (Fallopia japonica), buddleia (Buddleja davidii; confusingly the scientific name is spelt Buddleja whilst the English names are buddleia or butterfly bush) and Himalayan balsam (Impatiens glandulifera). There is an officer stationed near the entrance of the site to keep the curious at bay. We climb over the fence and walk forward. Soon we can smell decay.

When we get to the deposition scene, I discover that the police have cut down most of the vegetation and raked it into piles. Not a good start. Estimating the age of vegetation is largely dependent upon its being intact! The police officer removes the tarpaulin that covers the deposition scene. Although they have removed the mans skeleton and personal possessions, a lot of his body tissue and stomach contents remain spread over the adjoining vegetation. The smell is almost overpowering. I try and take in the experience, without appearing inexperienced. The officer accompanying me explains that the police believe that the mans body had been there for several months and that he had been submerged two or three times by floodwater.

The smell is very intense. It is so strong that the officer tells me that, This is the worst one Ive had in seventeen years. I resist the urge to tell him this is my first case. In fact, Im so determined to do the job properly and not appear nave that I get on my hands and knees and start to examine the decaying flesh attached to the vegetation very carefully. Now, the smell is overpowering and in the back of my mind I can feel the compulsion to retch, but I withstand the urge and proceed with my observations. I am looking at the stems of the Himalayan balsam, or rather Im looking at the bases of the ones that escaped the strimming. They are flattened against the ground and are partially covered in decayed human tissue. It appears that the mans body was either placed or came to rest on top of the stems. At one point my physiological responses threaten to take control and I feel I may be sick. I stand up and breezily start a conversation with the officer. My strategy works, and the upwelling of nausea subsides, so I get back down on my knees.

After finishing my botanical examination, I explain my findings to the officer, couching them with one major caveat, which is that the strimming and subsequent raking has rather damaged the vegetation basically, I dont have a lot to go on! However, the mans remains were laid on top of the partially decayed stems of the Himalayan balsam, an invasive nonnative species that is an annual. Annual plants usually germinate from seed each spring, grow, flower and set new seed within one year or growing season. For example, the common wild plant, thale cress (