The search for Scotland’s native forest apple: Malus sylvestris Rick Worrell and colleagues report on a project to survey and describe Scotland’s misunderstood and maligned crab apple.

or the past year we have been Out there in our woods there are crab • Occasionally we bump into on the hunt in Scotland for apple trees (M. sylvestris), which may impressive wild-grown apples in wild-grown Malus sylvestris be wild, or may have been planted. forests so why is it that we know Fwhich, following the Latin name, we Then there are wild-grown domestic nothing about their ecology or might think of as the ‘forest apple’. Of apples (M. domestica), courtesy of genetics? course, most people use the name ‘crab several centuries of casually-flung • Malus sylvestris is apparently a native apple’ and think of small, scruffy trees apples cores. To add to the confusion, species, so what is its distribution in hedgerows. But there is a whole lot Forestry Commission and some local in Scotland and what are its basic more to Malus sylvestris than that. authorities have planted Chinese crab ecological characteristics? apples (M. hupehensis) and Siberian • Elsewhere in Europe there is Let’s put to one side the question of crab apples (M. baccata) as part of their concern that hybridisation between why (on earth!) foresters might be mix of landscaping trees around conifer crab apples and domestic apples interested in wild-grown apples, and plantations, picnic sites and buildings; may lead to the disappearance of M. start with the practicalities. Several and in places such as Argyll, these have sylvestris, in exactly the same way that things make this task more difficult overcome staggering geographical shifts wild cats are affected by hybridisation than it should be. Very few people and started to regenerate freely. And joy with domestic cats. Is that a problem have paid any attention to apples in of joys, all these species are capable of here, and can we cast light on that by the wild so we do not know where interbreeding and hybridising. looking at their DNA? to look for them. And when we find them, we are seldom sure which Fortunately, none of those involved Attempting to answer these questions species we are looking at. in this project understood this at the by looking at literature is a non- start, or we might have thought twice. starter because there are absolutely We set off simply to answer some basic no scientific papers nor articles on Above: Crab apple and bluebells. Photo: Rick questions: the ecology or genetics of crab apples Worrell. p32 ISSUE 56 Reforesting Scotland AUTUMN/WINTER 2017 www.reforestingscotland.org Rewilding

Our problems in locating trees got similar features to the BSBI map: solved in short order when we got our • Strongholds: Dumfries and hands on two databases. Firstly, we Galloway, Ayrshire, Eastern Borders, found that there were 25 trees listed Loch Lomond/Trossachs, Perthshire. on the Ancient Tree Hunt Inventory. • Blanks: Pinewood zone and the Secondly, we extracted locations from northern Highlands; seemingly the National Biodiversity Network anywhere with seriously acid geology. and we got hold of the Botanical • Intriguingly little in the western Society of Britain & Ireland (BSBI) Highlands. distribution map (Fig. 1). However, this map comes with an important While the NWSS was hugely caveat: helpful, we have since discovered that the crab apples recorded actually “This map covers both the native include all the various species and M. sylvestris (crab apple) and the hybrids mentioned above, and the alien M. domestica (domestic apple) quality of data varies hugely by and…the two species hybridise and region, according to the skill level of seem to be connected by a range of individual surveyors. Frustratingly, intermediates, which are included on nearly all of the records in the western the map…and all records are mapped Highlands turned out to be false as if they are native.” positives (they were not apples at all). So whilst that is an interesting At the time of writing (July 2017) map, we do not know if it really we have visited about 160 trees on tells us anything concrete about our way to a target of 200, and have the distribution of M. sylvestris. taken DNA samples to allow Royal Botanic Garden Edinburgh (RBGE) to identify them to species and their published in the UK. And the few hybrids. In addition, we recorded sections in British forestry books on the key morphological characteristics apples make quite a hash of the topic. and tried to identify them to species So it seemed to us that there was this way (true crab apples have something worth pursuing: a Scottish small leaves that are almost entirely native tree which we collectively hairless on their lower surfaces when know virtually nothing about. viewed though a hand lens). We then recorded the dimensions of the trees Looking for apple trees and the basic ecology of the sites We started the search for wild- where they occur. grown apple trees by getting the word out to likely suspects: Discoveries to date foresters and ecologists who know The first thing to say is that most their woods and keep their eyes Fig. 1. Distribution of Malus sylvestris in Britain trees are magnificent, characterful open. Confounding expectation, this according to the BSBI. and deserve to be celebrated and yielded very few trees. However, it did reveal some intriguing insights. Some Lastly, we discovered that the people thought that Malus sylvestris wonderful Native Woodland Survey was not native; others regarded of Scotland (NWSS) recorded all wild-grown apple trees as feral apples, and Forestry Commission domestic apples, and some thought Scotland kindly sent us a file with that all crab apple trees had been 900 polygons containing crab apple planted. This seemed to run counter trees in Scotland. We used this to to our field experience, but we have produce a map (Fig. 2), effectively kept some of those misgivings in giving a second distribution map of mind. crab apples in Scotland, with several

Our experience is that crab apples are exceptionally attractive, and a crab apple wood in spring is as magical as any native wood anywhere. So we ask Fig. 2. Location of woods where crab apple is recorded in the Native Woodland Survey you simply to take notice of them, and of Scotland (data from Forestry Commission think of them as Scotland’s forest apple. Scotland). www.reforestingscotland.org ISSUE 56 Reforesting Scotland AUTUMN/WINTER 2017 p33 Rewilding

treasured, rather than ignored as has that the current era presents fewer into the landscape. So the main largely been the case to date. In terms opportunities for regeneration endgame of this project is to find of numbers, they hit the sweet spot than times past. That said, we have a good selection of such trees, and where they are common enough to observed that crab apple trees flower bring these together as grafts, and be ecologically significant, but rare and fruit profusely and the fruits form seed orchards. This is probably enough to be notable when you find mostly have a good number of viable the only reliable way to get seed into them, rather like aspen. seeds that germinate easily. the nursery trade. There may also be areas in Scotland where genetic The biggest trees are larger than So far we have found very few conservation in the wild is a smart reported in the literature; we have beside old habitation such as farms, idea, such as Loch Lomond and parts found trees up to 15 metres tall and clachans, and sheilings. So where of Kirkcudbrightshire and Galloway. some get close to a meter in trunk you might expect to find other And we would like to know more diameter. They are mostly old, we co-habitees with humans, such as about how to regenerate them in the are guessing 100 to 150 years, and a rowan, gean and sycamore, you do wild and about historical ties between high proportion are veterans trees. In not find crab apple. However, they people and crab apples. upland areas (such as the southern are common in both wood pastures, Highlands, and Dumfries and often as pollarded trees, and in Crab apple trees suffer from an image Galloway) the vast majority appear hedges, suggesting past management. problem. The common name, and to be self-set, rather than planted, There is absolutely nothing about the its colloquial equivalent ‘scroggie’, though planting has no doubt distribution and ecology that suggests derives from words meaning small, happened. In the lowlands, as with M. sylvestris is anything other than a untidy and scrubby. Its genus name other tree species, most appear to bona fide native tree. Malus, means ‘evil-one’: think of mal- have been planted. words like malformed, malice, malaria The vast majority of the trees are (=evil air), dismal (=dies-mal or bad Crab apple trees occur at elevations in rude health. They appear to be days) and many more; because the from sea level (we even have a incredibly resilient. They blow over apple was the evil fruit that tempted sample from a sea cliff in Shetland and resprout freely as ‘phoenix trees’. Eve and led to mankind’s expulsion obtained by swimming), to about They frequently grow hollow then from the Garden of Eden (with an 300 meters above sea level; and collapse, but then get a second wind attendant whiff of misogyny). This is evidence from the Lake District and start growing again. Broken limbs quite some cultural baggage to burden suggests they are capable of growing will live on and recover provided they a small tree with. Our experience higher than this. We found them in are connected to the main stem by is, after 160 trees and counting, native woodland, both ancient and the thinnest strip of bark. So far we that there is nothing ‘mal’ about secondary, in wood pasture, in fields, have only found one tree apparently them; crab apples are exceptionally hedges, and along railway tracks. A affected by disease. attractive, and a crab apple wood significant proportion were found in spring is as magical as any native in upland gulley woodlands. There Based on their morphology, we wood anywhere. On the continent, is an interesting population at high estimate that in the uplands probably crab apple trees are regarded as tide mark on the islands in Loch 60 to 70 per cent of wild-grown ‘noble hardwoods’ capable of timber Lomond. They appear mainly in apples appear to be true M. sylvestris production. So we ask you simply oak-birch woodland (NVC W10/11) rather than hybrids or other species. to take notice of them, and think of and ash woodland (NVC W9), and In contrast, in the lowlands, domestic them as Scotland’s forest apple. occur mainly on brown earth soils but apples and hybrids appear to be in the sometimes stray onto gleys. majority. But until we look at their Acknowledgements DNA (which is work in progress) we This paper is dedicated to the We found very few crab apple do not know for certain. memory of Patsy Wood, who loved seedlings and saplings, suggesting all things to do with trees and woods. What next? We wish to thank the Patsy Wood Below: Crab apple in a wood pasture; Large We would like to get a new Trustees, the Scottish Forestry Trust, coppice crab apple tree in Grandtully. Photos: generation of true M. sylvestris out Sustainable Forestry SCIO and Forest Rick Worrell, James Renny. Enterprise Tay District for supporting this research. Rick Worrell is a forestry consultant specialising in the silviculture and ecology of broadleaved trees. James Renny is a self-taught ecologist and wildlife artist, and now one of Scotland’s few wild apple experts. Markus Ruhsam is an expert in plant hybridization at RBGE. Will Jessop is an MSc student at RBGE. Graeme Findlay is conservation manager at Forest Enterprise Tay District. p34 ISSUE 56 Reforesting Scotland AUTUMN/WINTER 2017 www.reforestingscotland.org