My dad can often be found staring intently at a tree. He may well be holding a hand lens or caught carefully folding a white paper envelope. For a botanical recorder, this behaviour is to be expected. It is how you decipher the code that will reveal the identity of a tiny, green moss.

Growing up I accompanied my dad on countless plant hunts, searching for species only a few centimetres tall. At first, I assumed that everyone must find fascination amongst the green and red sphagnum bogs of Dartmoor or in the buzz of a spring meadow. Alas, I soon realised that the adventures of botanists are as little recorded as the rare species they seek.

Dad - or Brad Scott, as the world knows him - is currently a botanical recorder for the Sussex branch of the British Bryological Society, essentially a national moss organisation. He specialises in bryophytes, more commonly known as mosses, liverworts and hornworts. Often considered a nuisance by lawn aficionados, bryophytes rarely receive the appreciation they deserve. But dad and a community of volunteers around the country are steadily submitting their findings, complete with precise grid references, to the national data set. Their data is used by biological records centres around the country to inform species-distribution maps in field guides and planning-permission requests. If particularly rare species are identified in an area, it is less likely that it will be approved for building. “The reason why it is so important is so that people can monitor plants long term and understand how things change over time,” he explains to me as we walk through a birch woodland in Ashdown Forest.

Like many enthusiasms, an interest in bryophytes crept up on my dad quite organically. Ever since he donned some hiking boots as a teenager, he has wondered what grows underfoot. Today, as he visits unrecorded corners of Sussex, he is likely to be able to tell you exactly that. “It kind of forces you to go to places that you wouldn’t ordinarily go to,” he says. “Even here, an area I thought I had explored very well, I wandered up to a wood last month that I had never been to before. It was only a mile from the house and I found a moss that I have never seen in Sussex before!” 

Yet my dad’s attitude to exploration has not always been so focused on the local. He held a naturally inquisitive approach to place while on holiday, especially abroad, but noticed that this was not something he necessarily retained upon return. “I think this realisation made me a lot more conscious to notice stuff locally, and then I found how much that enriched my experience of living somewhere. I also appreciate that we are lucky living where we do, only a mile from this wonderful habitat.”

As we emerge from the trees onto open heathland, I wonder what came first: a knowledge of plants or of the local landscape. In a true chicken-or-egg scenario that perhaps I should have anticipated, my dad says he can’t imagine one without the other. Indeed, questioning why plants grow where they do is crucial for a botanist. He considers everything from the acidity of the soil to the underlying geology when identifying a moss. “Even within tens of meters, a habitat can change drastically,” he says. 

Like many others before him, William Hoskins’ The Making of the English Landscape proved particularly influential in shaping my dad’s view of local land. “I think it opened my eyes to the idea of local specificity and the impact that people have on the landscape,” he says. As we take in our surroundings, he observes that this apparently wild expanse is, in fact, very much managed. Traditionally a royal hunting ground, Ashdown Forest has since been shaped by grazing animals and conservation. “It is certainly not natural,” he states matter of factly. Human impact on the land is not something he sees as inherently bad, though due in part to agricultural and housing pressures lowland heaths are now scarce in the UK.

Despite the decline of these lowland habitats, there remains a rich diversity of species living within. Speaking with infectious enthusiasm from the centre of a bog, dad points out several within a single square metre. These wetter areas are extremely rich in life, home to a huge variety of coloured sphagnum bog mosses, each with their own microbiome. Living peacefully alongside them is the beautiful bog asphodel, as well as the insectivorous sundew. But some neighbours are more tolerable than others. Whereas the deer grass keeps to itself, the purple moor grass has taken root where it is unwelcome.

Amid all this diversity, dad warns that this bog is currently in a state of change. Not only is purple moor grass taking over, but historical records show that there were several species -including bog orchid, moonwort and pillwort - that previously thrived in Ashdown Forest but are now extinct locally. “Extinctions are not just things which happen to charismatic megafauna somewhere else in the world,” dad says sadly. “You get things going extinct locally too, and it is through stopping and looking at the micro-plants that I began to notice this.”

As we make our way across the heath, he continues: “There is some change which occurs naturally. But then a lot of it is certainly down to habitat loss or human-induced pollution. Pollution really has changed things a lot, but also it is the expansion of agriculture that causes destruction and extinction.” 

This visible disappearance of plants from our landscapes must be especially harrowing for those who dedicate their lives to monitoring their existence. Indeed, united by their willingness to scramble down banks and wade through rivers, my dad has met a community of botanists, some of whom are well into their eighth decade. “He has been botanising in Sussex since his teens,” dad says of one such friend, “so he has got that kind of long memory of what it was like then. You can go to very specific places with him in the forest or elsewhere and he can tell you exactly what was growing there 60 years ago and then can tell you what is missing.”

From this multi-generational vantage point, we see an example of shifting baseline syndrome. When we look out onto the natural world today, we may take the picture we see as ‘normal’. Yet this is far from the truth. For instance, since the 1930s, we have lost 97% of the UK’s meadows. The species records collected by botanists play a key role in reminding us not only what is under our feet, but also what is no longer with us.

I wonder if my dad has felt increasingly determined to protect the environment as he has learned more of the natural world. “Yes, because I have invested time in finding out and walking and discerning differences. But it is not a requirement! A lot of people are keen to conserve the natural world without necessarily knowing all the fine details, and no one knows everything.”

I can’t help but smile at how long it had taken us to walk a relatively short distance. What a contrast to running or cycling, where you whistle past the world far too fast to observe the geometric intricacies of a bryophyte. When I point this out, dad is far from offended. “You don’t have to go very far, nor very fast!” he exclaims as we return to the wooded beginnings of our walk. 

“One thing about doing small plants is that your scale changes,’ he continues. “You can be looking among mosses which might only be a couple of centimetres tall. You see this whole little universe of tiny animals that you might not even otherwise imagine - little insects, springtails and mites! There is a whole forest of interactions going on which is equally as complicated as this larger forest that we are in now. You just start to notice difference, and these tiny, small things. And you know,” he finishes with a smile: “that’s an adventure in itself.”

You can hear more from Brad on at his blog or on Twitter.