Sorting the wheat from the chaff in Kent cropmarks

Description: Ever wondered how to identify archaeology from the sky? Who knew that you could use your computer to scan the rural fields and valleys to spot potential archaeology that will tell you more about the landscape and heritage. UK Heritage charity the Kent Archaeological Society hosted a presentation by KAS Trustee Chris Blair-Myers which takes us on a tour of the skies above rural Kent to give us some tips on how to use cropmarks to reveal secrets beneath the soil. Join the KAS to support our work www.kentarchaeology.org.uk/join-kas Get in touch with suggested content or about volunteering opportunities communications@kentarchaeology.org.uk

Transcript: [Music] hi and welcome to the kent archaeological societies youtube channel my name is fred birkbeck the kent archaeological society is a charity based in the uk and we are dedicated to the promotion and education of archaeology and history of the fabulous english county of kent and we have a number of videos on our youtube channel covering all sorts of diverse topics by either a charity trustees or by invited guests and you should check them out uh you have some great information on there will really help you to understand more about what ken has to offer now this video is of a lecture given by one of our trustees chris blair myers on crop marks and how to identify them where to look for them and whether they are really denoting possible archaeological features or not chris is very well qualified to deliver this chris has worked for the department for international development all over the world on digital mapping and photographic interpretation for environments projects he's also worked for kent county council on the environs team and he has lent his fantastic expertise in aerial photographic interpretation to the archaeology sector advising the historic environment team on potential archaeology in the landscape in certain parts of kent so chris is a great brunswick society he works tremendously hard he's also responsible for digitising a lot of the grey literature from archaeology units in the county which a lot of which you can find on our website so if you want to support the work that kent archaeological society do please visit our website the website address is below and join it's a very reasonable price to join as a member and you'll be supporting a charity that are really trying very hard to educate people on this great county so i'll leave you with chris's video just one minor point of interest is that the video is pre-recorded so the cursor isn't exactly on the features that chris is describing throughout the video it's slightly to the southeast of where his cursor is so if you see that and for the first minute or so you'll get used to it it's the same all the way through the video and also i want to give special mention to dr lacey was of the university of lincoln who gave us permission to use some of the images from bourne park of the fantastic geophysical survey techniques that we use there and the results that came through and that pretty much ground truth what chris had interpreted so please enjoy the presentation and support the kas as best you can at the end there'll be a short question and answer session between me and chris discussing his presentation so please enjoy it good evening um today or this evening i'm going to talk about crop marks so what exactly are they they are actually the visible effects of vegetation responding to differences in available moisture and nutrients which is a bit of a mouthful so we'll stick with marks i have selected a number of aerial photographs clipped from google earth pro to illustrate these responses and in some small way look at distinguishing between those that may have a response to archaeological features and those that have an altogether different cause all by one of the images are from kent first up is an aerial photograph of the golf course at sandwich bay which is the royals and georgie's which is a dune system and it's been taken in mid-summer after a fairly dry period the dunes form ridges running roughly north-south into space by low-lying slacks the slacks are the closer to the water table and they have a higher humidity content and they're appreciably more personal than the thin free draining sandy soils on the dunes that rapidly desiccate in dry weather the brown parched grasses on the sandy soils you can clearly definitely differentiate it on the lush green sword on the slacks the closely known spareways which are these here show up as brighter strips but they have no impact on the crop marks beyond improving the boundary definition between them similar effects can be a result of subsurface archaeological features that create variations in soil depth causing vegetation over these features to show differential growth or ripening at a different rate to the surrounding vegetation this is my uh drawing of my own wonderful hand it's supposed to be wheat but i'm sure the purists amongst you will know she said it does look remarkably like my maize but what i have here is supposedly say a chalk uh geology with a fairly shallow solid over the top and then we have a ditch cut here and then the remnants of possibly a wall and foundations here and what i'm trying to show you here is that because the ditch has been backfilled and usually with a fairly nutrient rich soil the crop over it will usually grow taller and moreover uh beyond the less moisture stress so it tends to remain greener for longer whilst the crop either side of it responds in a normal way it is beginning to go to yellow and ripen as you can see it still stays at dark green in the middle over the rays feature the soil is much shallower so they have problems with group growth it doesn't extend down far enough so it has less moisture but also it dries out far more quickly so effectively it stunts the growth and it also especially wheat tends to make it ripen earlier seeing the patterns that this perform is created it can be seen from the ground but it is extremely difficult so it's much better to actually look from aerial photographs where you can actually discern patterns more easily here i've got a series of crop marks of ring ditches there's a vintage here another one here and an enclosure the sun is actually placed as you can see from the shadows from the bottom right hand corner this is slightly counter intuitive because the ia is usually trained to actually have a light source from the north west corner up here and so some people may see these not as raised features but as sunken features if i flip it brown so we get the shading from the northwest hopefully you'll see that more clearly and these now could be clearly seen as raised wheat in an otherwise flatter environment this is a a crock mark of a double-ditching enclosure with a causeways entrance with other non-contemporaneous boundaries running around it well these ways sure and it's remained green longer so it's a similar effect to the last slide but this is to do with the maturity of the crop rather than just it growing taller with modern agriculture and um if you like with uh the amount of fertilizer and how it's spread it's quite unusual to see a crop growth differentiation but you will still get to see this ripening effect in fact the soils associated with the big broad ditch here can actually still be seen as a soil mark running approximately there so even though there's no crop you can still see it as a mark this effect is not just in ripening wheat you can also see it in early spring wheat and the next one here we have a an unusual series of crops and crop marks which the ring ditch is clearly obvious there and well marked with a slightly more wobbly second ring around the outside and it could be that of course the they may not be contemporary but what you have got is a very shallow soil over a chalk short geology and in spring the wheat is taking advantage of the ditches which has got a greater depth of soil to actually motor on and effectively grow quicker these numerous little oblong features here are in fact probably an anglo-saxon cemetery and if you look carefully you can see around here there's a couple of small ring links with a central probable grave cut in the middle these are probably anglo-saxon barrows elsewhere where the plow has actually reduced the soil to a point where it's actually removed the barrows you'll just see them as a very faint halo around the grave cut the other feature here which looks like a feature but in fact it's a result of agricultural practices because here we have a pylon in the middle and where the uh the machinery tries to duck around it you create these artificial square-like shapes and forms which can be very misleading if you don't notice that there's a pylon in the middle of it elsewhere we have other dishes but you can't really be sure what they are negative crop marks or parchments are usually where the if you like the the soil is of inadequate depth and so you get moisture stressing in this case in grass and here you can see the rectangular form appearing of what is actually a roman structure just near why next to the river style i've actually actually contrast stretch this to try and bring out that shape and form what is less certain is whether or not this is actually caused by the actual foundations themselves since this feature was actually dug in the 60s so what we may actually be looking at is a backfill of the excavation trenches so there's some uncertainty about whether we're actually looking at the archaeology or the result of the archaeological interventions it's rarely this obvious so if i go to another example this is actually in fairlawn park and blackstorm and you would have to be extremely well good eyesight to spot that in the middle of it it was in fact a roman building uh it is barely discernible around about here but this is normally what you get when you're actually looking through imagery when you're trying to find front marks you're really are looking for a needle in a haystack and if i put on the excavation plan as it was subsequently excavated because of a pipeline going through it the proposed line went through there which they actually changed to avoid going through the middle of the uh the roman building and you can quite clearly see here their own building there if i then move on what i can do is if i zoom in and actually do another contrast stretch on this you can now see a little more clearly that is where the building is and this is the new alignment that they made for the quiet way to avoid going through negative crop marks in crops are actually quite rare uh the 2013 image on the left shows three small killer circular features where the crop is stunted and pale there's one two and there's a third one here this is an immediate obvious what we're looking at here in fact you can also see that there's a very pale line coming around here so all those who have interest in second and the 20th century wartime defense systems will maybe recognize that and if i go to the 1946 image you immediately recognize it as it's a heavy anti-aircraft a battery and what we're looking at is the the gun platforms of at least three of them are visible the fourth isn't really really to be seen so there are several factors that can influence the creation of crop marks it's a key element in variations of solar moisture the weather can be critical and periods of drought particularly in late spring and early summer when vegetative growth is peaking can produce particularly good conditions for crop marks doubt droughts may have very little discernible effects as the vegetation is dormant and late summer droughts can have little visible impact on ripening crops or grasslands that are already parched and brown in drought conditions the speed of which a crock mark develops is very dependent on the nature of the soil soil consisting of coarse particles sands releases water steadily to sustain plant growth but can be exhausted abruptly crop marks on these soils can develop in a matter of days soils consisting of fine particles clay retain water releasing the moisture to plants at a decreasing weight as they dry the reduction in plant growth takes place over a far longer period and it may take several weeks for crop markets to develop if at all in both instances a fresh ball of rain would restart the whole process and even if weather conditions are favorable there are a number of other factors that militate against the appearance of crop marks soil creek may reduce soil depth on the interludes and colluding recreating in valley bottoms to a point where subsurface archaeological features are too deeply buried to affect their vegetation soil loss on the interviews exacerbated by frequent ploughing may reduce or completely remove all but the most substitute substantial archaeological features on subsequent crop market this can give the entire misleading impression that archaeological features are concentrated on the genuinely sloping flanks of valleys here is an example taken from the planet the dry valley which is the dark green black is actually only one meter lower than the surrounding land but the difference in soil depth is sufficient to affect the crop growth obscuring a section of the world or two i think slit trench that runs across it it will be there so surface geology is an important fact where the composition of a ditch field is very similar to the surface geology as is often the case for clays or wetland soils there is insufficient contrast between the ditch and the natural to create a differential effect on the vegetation except under the most extreme drought conditions for example there are very few crop marks recorded in the kentwood and claims an excellent example with the extensive romano british settlement at west halt farm ashford the site was revealed by a geological geophysical survey conducted prior to construction of a large housing development but although it's very extensive and complex it had not produced a single significant crop mark in 10 to 10 different sets of aerial photography flow between 1946 and 2013. the type of vegetation cover can also be significant natural grasses are habitats that are composed of remarkably rich and complex mix of grasses and forms adapted to site conditions for example chalk grassland communities are particularly suited to hot dry sites and unlikely to produce parchmarks even under drought conditions so the complexity of the species mix enables the community to accommodate seasonal fluctuations in weather what may be detrimental to one part of the community may cause the other to thrive so there's no overall discernible difference in the vegetation when reviewed from a distance improved guard grasslands respond somewhat differently as their species poor and they lack the adaptability of natural grasslands indeed sunglasses are plowed and soaked with a very limited variety of grasses and flavours and respond more like a cereal crop they are often known for hay or silage my short and a short sword should add clarity to clock marks although they can reappear when the cut grass recovers three draining soles and alluvium sands and chalk can provide very marked contrast to ditch fields and under ideal conditions produce crop marks for remarkable clarity parts marks in these slabs can be very fleeting as they appear at all as the soils desiccate rapidly these soils cover much of northern and eastern kent and for this reason the overwhelming majority of crop marks recording at kent are ditches found on these formations pasture or immediately glasses but the sword is maintained in short grass can be more rewarding plot marks in lawn are usually produced by parching negative impart marks appear first as the grass browns over varied walls and pavements as the drought continues the grass browns over the remaining shallower soils leaving ditches as the greener positive crop marks this is the roman structural complex at bourne park in kent appearing as parchments which you can just see here at the edge this was deployment in 1990 and it revealed right in that northern corner next to the cricket pavilion the outlines you can see there this is on the alluvial floodplain of the seasonal nail borne stream and has been grazed on known parkland since at least the mid-1800s in fact this is a very well-known cricket pitch for those who have an interest in the game it's been in existence since at least 1760 when the first counter-class cricket matches were actually played on that ground so it has had no agricultural interference when we look at the slightly later edition this is in 2003 which was a dryer yet but the aerial photograph was taken later so already up here where you saw the earlier marks they've almost faded to nothingness because all the grass around it has already started to brown but here you can now see what looks like little t-shaped panics appearing so this confirms that what we have is definitely some kind of structural complex of some kind fortunately this site has also been surveyed both uh by magnetometry and resistivity and in fact by ground penetrating radar so what i'll do is i'll show you some of the results from that so you can see what effectively you can see as an aerial photographic crop mark and what you see when you actually do say this is magnetometry there's the t-shaped alex again but to our surprise when we did it we suddenly found there's a whole range of buildings popping up over here on the right hand side if i briefly revisit the story about the cricket pitch these rather curious if you like dipola responses here are actually 22 is it is it a chain like 22 yards i could have been the witch but actually other stunts if you like for the uh for the cricket pitch which must have actually been very very heavily impacted on to actually create these marks over where the wickets previously stood it was also done with the high-res resistivity um this clearly shows up the boundaries of the walls including entrance ways uh passages coming into the various rooms and even what are probably quite substantial structural elements of the main entrance which you think is this in we also put a ground penetrating radar over the top which i'll run through now this is a movie if you like which is done by looking at the radar results done with five centimeter depth slices so i'll run through this so you can see that's the top and now we'll run down through as we go down you'll start to see the walls of the structures beginning to appear and we continue down through them there's even a back wall that's here and this is an absolute end which subsequently proved to be a bath complex at the end and it will continue down until we get through out through the bottom of the uh foundations and back into the natural it did reveal a very broad dish here which seems to be exist prior to the construction of the building but we don't know what period that would be from okay let me see if i can now move on to the next one okay so crops are monocultures with very little genetic variability and developed to respond to uniformity weather and soil conditions this uniformity response is very useful as all the crop above the archaeological picture will behave in a similar way creating very clear cut marks but not all crops have the same degree of sensitivity large crops like shrub or fruit orchards have deep and widely spreading root systems that reduce this sensitivity to localized variations in soil moisture they still occur particularly where the subsurface feature is broad and forms an impenetrable layer and is near the surface an example below flowed in 99 and 2003 the apple trees planted in the mid-1990s have failed to reveal a curvilinear feature there's no certainty about what we're looking at here but we suspect it may actually be the edge of an old reichstone quarry the notable exception of maize cereals can generate excellent crop marks their limited root root depth and spread are sensitive to localized variations in soil moisture and the close planting of the crop gives good definition revealing small features in high resolution aerial photography this is a field of spring weed the field boundaries and ring dishes are obvious but it's also possible to see a line of pits or post holes leading from the center of the image from here going down towards the series of integers down here to give you some idea of just how good the definition is here each of these pits is actually less than a meter across so this is a very fine resolution that you're actually looking in the crop mark the rest of the features uh are slightly more difficult to explain but we suspect that these might be sunken feature buildings i mean the ring ditch is fairly obvious and it appears to be some other possibly later burials here and again this slightly wobbly second ring around here may actually not be contemporary with the first some of the others are fairly obvious so we've got a trackway coming through the top and an enclosure here not all crop marks are archaeology although the aerial photograph for the sandwich students illustrates vegetative responses to differences in soil moisture that are natural in some instances it can look remarkably like archaeological beaches in north kent the sanic bands beds are formed in layers of clay sands sands and calcareous sandstones in thin beds and where laid horizontally and eroded the small variation in soils can create patterns that look like archaeology in this photograph the resulting pattern looks remarkably similar to the banks and ditches of a small iron age port in fact it's not it is rather small although saying that there is a small circular feature on the top here which actually may actually prove to be a ring ditch equally periglacial action on clays and sounds can produce distinctive geological patterns and this includes the poly polygonal ice wedges commonly found on the london clays in north kent they are striking these similar to prehistoric field boundary ditches as can be seen on the image from the who peninsula note the two faint ring dishes here and here adjacent and the ice switch pygons do pass through them it is quite hard when you've got this sort of patterning to actually work out what is archaeology and what actually is a geological feature in the corner down here we have further what i think is psychology with a field boundary ditch running here and here but in here possibly it could be ridge and burrow you can see these very closely spaced curving lines here it is very hard to you should certainly on those but try to unpick uh archaeology from this can be quite challenging for comparison i'm looking here an image of the midway floodplain eastern top bridge here we can see it's a similar pattern but in this case you're looking at a network of paleo channels and former drainage dishes built in by agricultural conversion from pasture to arable post 1946 these this form and shape clearly shouts at you that you're looking at an old river bed and there are others flipping around here most of the others are the drainage tissue ditches associated with uh in this case probably fairly modern boundaries but some of them may not be they actually may be older it becomes a little more obvious when you look at the 1946 images and where you can still see that some of those stream beds are still a visible feature actually in the landscape human activity can also create ephemeral crop marks that are not always easy to explain this particular one was pointing out to me from someone in the darren valley which when i first saw it had been completely baffled it does look strikingly similar to ostia and antica with this arrangement of kind of seeming piles and little sectioned maybe buildings and then these kind of almost like an arena hippodrome whatever but with a bit of research it turns out that this field is actually used for the kent heavy horse show every every year and so what i'm looking at in fact is the arena for the show with the entrance to it there and then a side arena and then a number of probably fairground showground walkways and possibly even a merry-go-round these marks would have been very ephemeral and it was just pure kismet if you like if it happened to be photographed at this time because with the first set of rain these have all vanished equally confusing and giving you problems are old playing fields circular features can be found in old sports fields where repetitive white lining of football pitches around central circles can compress the soil leaving patch marks in dry years long after the field has changed use in this instance it's quite helpful in fact we still have a running track round here which tells me about i'm looking at a sports field but some of these otherwise have been very hard to explain but what we're looking at is the boundaries of various well you can see what maybe a half circle for a uh football pitch here although this is actually from the girls school at benedine so um i got slightly confused about one of them which turned out to be a lacrosse pitch which i have to say i'm completely unfamiliar with but circles as crop marks can appear from uh quite a remarkable number of different um sources this one which looks wonderfully like a parchment but in fact it's um associated with equestrian training so novices would normally be trained to ride with a riding master in the center but the horse on a lunge or a rope or a fixed to the to the bridle of the uh the horse and then they were dropped and counter around in a circle being managed if you like and so one and a half tons of horse running around in a circle for extended periods of time can actually compact the soil quite remarkably uh the clue here in some ways is hey well there is okay there's a jumping post there but we've got another lunge training ring here and you can see that the horse pastures are coming up in here all this paddocking so we know that there's something equine going on in here and so that would explain almost certainly what that is it's certainly not archaeology as we would know it elsewhere again looking uh following on from the hall c factor this is actually up in gillingham on the great lines and what happens here is that horses are grazed by putting a central stake and then the horses actually change the stake so it actually browses into a circle and presumably in its efforts to actually get to the slightly sweeter grass just outside its reach it tends to actually form like a marks trampling around the edges which again when you first see it it does look remarkably like a cluster of bronze age ditches uh ringages but it definitely isn't this is very horsy again in other instances uh you'll get rings that appeared to be archaeology but in fact again are perfectly natural this is a ring ditch of some 18 meters across shown in the moon meadow in 2003 but when i looked at an earlier image it's still there but mysteriously shrunk in fact this one's only 10 meters across and if i looked at the intermediate ears you see it's slightly bigger so what we're looking at here in fact is something that they refer to as fairy rings they're caused by fungi which and there are a number of species responsible and some have no visible effects on the grass but others locally increase available nitrogen creating a positive crop mark whilst others in the group the associated bacteria coats the soil the waxy substance making the soil particles hydrophobic creating a parched mark this photograph actually shows a small ring formed by a blue fungi and then these the ring expands at approximately a meter every year so it just continually grows out and you'll get a larger and larger so if you're looking at ring marks it's always worth looking at an earlier to see whether or not it has mysteriously shrunk but not all ring clusters can be attributed to the fairies this group is almost certainly an anglo-saxon marrow symmetry the oblong are rectangular features within the rings or a significant clue as is the closest of the rings the fact that they form a cluster you can see that there's a you know quite a very tight group and they're almost touching and inside some of them you can just about make out what is probably the grave cut there's no one there no one there the size is a little bit variable but they're remarkably consistent between sort of like six meters and ten again there's another ditch down here which is substantially larger and it seems to be a curious factor of anglo-saxon centuries that is often an association with a much older prehistoric uh burial mound of some kind and this seems to be the case here but these can't be confused with prehistoric ring ditches and i'll show you an example of what is probably a bronze age and again you can see that they're far more spread you know it's very rare that they touch they're also something substantially larger and in this instance the central what is probably a burial in here is not a rectangular or oblong but a good deal more circular you can also see that there are probably later uh internments around the edge of the ring here here here and there which is again not quite a common practice i believe with uh certainly with bronze age barrows but again not all rings are actually barrows if i look at this one we can see the familiar ring of what might be a barrow but in the middle of it we have a kind of x marks the spot um the x actually is the cross trees of windmill so so post medieval windmills had substantial wooden found cross foundations which supported a central pillar on which the the windmill actually stood and rotated round what you're not clear about is whether or not that they've actually taken a bronze age or earlier um barrow and recycled it as a windmill barrow or whether or not that is actually the borrow ditch to create the mound for the windmill again you can't really tell until you actually go and explore it but it's more common to find the cross without the ring so this is an example which is more well obvious and more common so it's not uncommon to find just the x but again you can see you've got the halo around it where there was once a mound so the game that windmill was still cited on a mound earlier when i was looking at the isle of grain i did make a mention here of ridge and paro vision furrow is actually a very common distinctive agricultural feature of a medieval landscape but kent has been under such intensive parable cultivation and it's an extremely rare feature to the point where i couldn't even find an example in areas that i could reliably say was richard pyro this example in fact is taken from an abandoned medieval village in northamptonshire what is notable and if you like one of the key features are these what they call the like stretched s-curves which are if you like one of the main signatures for original paro so where you see this there's a high probability that's what you're looking at there are a number of places in kent where you appear to get rid of arrow but they're not and so if i go to the next slide which in fact is nor marsh in the middle of the medway estuary now it is now salt marsh but previously it was enclosed probably in the late medieval or possibly even post-medieval period it was enclosed with flood embankments and put down either to grazing or agriculture and what we're looking at here is some kind of like artificial rich empire that they've tried to drain and improve the soil by making shallow ridges uh and furrows between the most obvious thing when you look at this is is just how straight they are they are there's no that sort of slight curving feature that you get on ridge and burrow that doesn't mean to say that there's no archaeology here and this almost certainly was terra firma at some point i mean the whole area is well known for having a large number of certainly roman uh pottery kilns on these islands and some of which have actually been excavated but if you actually look at an earlier image of this uh before it turned to actually this is spartina which is a salt marsh you'll see that here we're looking at a number of what are probably uh salsa barrows so certainly it was terra firma at some point in prehistoric terms and that's a fairly firm evidence of what you have so this if you like are the drainage channels but they were probably discontinued somewhere around about 1800 so instead of doing kind of artificial ridge and furrow they started to build effectively a different sort of drainage using ceramic uh piping so here is another wonderful example of one man working down a trench being observed by a large number of people with suits a site not unfamiliar with uh modern road works and he's actually putting down in this case circular terracotta pipes in a long straight uh drainage line uh sometimes these pipes that can be horseshoe shaped and some have holes into actually water to percolate through but when it's finished and it's done it generates and creates a very distinctive pattern so when you're looking at crop marks and here is the example uh you've got this very distinctive herringbone effect turning up and this is almost certainly uh post 1800 and probably even later uh drainage lines again where this you've got archaeology underneath it although strictly speaking this is of course archaeology but if you're looking for something more ancient it's extremely hard to see when you've got this interference pattern going over the top of it and so finally i come to my last slide which is not exactly a word from my sponsor but what you can achieve if you've got a lawnmower and a very good sense of spatial awareness so you can go out and create your own marks this one of course will not confuse anybody so at that point i shall leave you and thank you for your time many thanks to chris there for that um presentation now chris has actually joined us uh for some live questions and answers if you want to submit any questions to him um that was a fascinating talk as i say i'm very uh much into the archaeological perspection myself a bit on the ground with the near surface stuff uh the the i have used them aerial photography but that i've learned an awful lot from that um so i'm really excited to to kind of get on the the google maps with a glass of something fizzy and uh just beaver away at it really so chris um can you tell us what what's uh what sort of uh outcomes have you had from the work that you've done on this uh crop mark analysis uh can you think of anything particularly oh not really just um only in the sense that we turn up an awful lot of very new sites um i haven't exactly been keeping tabs on them i think uh as an example i think the first crop market was done in about was in 1968 i think by the royal commission and an analysis of that turned up the suggestion that there are about 800 ring dishes in kent at the moment i'm around about 4 300. so there i think is a slight undercount in previous attempts um other than that i think we do quite surprisingly i mean the uh the villa i think at ball park is well known but we have now identified at least another four that were not previously recorded and we have turned up quite a few uh potential saxon cemeteries that weren't previously recorded no really huge ones and i'd say enclosures by that there's quite a lot of material that hasn't been known before most of it i actually just i send on to the uh to be included on her you know so rather than just sit here and say oh yeah i actually sent it forward to the uh the officer so it gets properly recorded i know that you and i have um had conversations about these before and particularly with regard to the villa sites or potential villa sites on the main rivers in kent and i know that's something that that lacy wallace was uh looking at particularly on the store and um you've you've had a lot of success for looking for things on on medway and and on the dharam what kind of patterns have you noticed from those i think the one that i wasn't expecting i mean everybody knows perfectly well the number of roman villas particularly on the north korean coast that may be associated with some of the inlets and the close proximity to the wattling street well i was a little more surprised to find that there was an equally another string of them that run along the foot of the downs so all the way from ashford there's probably one almost every one of the half k right along the spring line going right away through to mason and onwards uh through scotland and then up to uh crossley we think there's not burling and so on and then we've uh and they come rightly around uh through to the sussex border so that i wasn't entirely expecting um the other thing we noticed that was again a little surprise was that a lot of this information has been lost because it's on the map and if you look at it you suddenly says that roman remains found here uh and then they've been promptly lost and they're not uh they're in the record somewhere but they kind of got lost to general knowledge in a sense so i think someone's a bit surprised to find just how many there are and there's a substantial cluster around maidstone but curiously there isn't a substantial cluster around ashford um so what's going on with mason i don't know um i'm sure it's not house prices the um [Music] so we were expecting to find a whole string like the durant all the way up the star but that's proving to be very elusive it's the one that why you've seen uh i have found another one that's not too far away from it i think biting is it not bill yeah which is uh yeah yeah a little further towards canterbury uh again in the foothills this time quite small i mean we're talking that probably just uh you know nothing very grand or grandiose it's quite modest little thing but it's definitely there but i found none between there and canterbury and it's the same i think that's why born created so much interest because it's the only one we know at the moment between dover and canterbury she must surely be others i mean the ellen valley is just too attractive a proposition so sometimes i'm looking because i'm thinking there's going to be something and then usually profoundly disappointed i could find nothing a lot of times things pop out the blue so the one at boxy for instance i was i only happened to look there because i went for a walk there and suddenly kind of singing pot on the ground and so i was like yeah so then i went back and looked through photographs and sure enough there's a um there's a villa there oh this way so we think is it i mean you were there and had a look at it so there's definitely um material in the ground there but uh whether it ever gets looked at i don't know i think that's one of the most important uh things to think about in terms of what you your approach so we can be looking at it from you know simply skirting the landscape looking for something that's brand new never been discovered before and then peeling that layer away to go in with perhaps some magnetometry survey resistivity uh that's then maybe intrusive investigation with some evaluations or test pits uh and then then the next steps forward but it can also work as i said kind of in the introduction work the other way around so if you are field walking you find some material uh in the field uh then you know get back to your computer check the hdr first see if there's anything on there that's uh indicative and then you know have a look on google maps or i'm sure others are available and see what what you can find yourselves nice is very true and i certainly welcome as many eyes as i can i mean people who find them and how but i want to show them to me and i'd be happy to see them although i would appreciate if like you say they actually look at the hair first so rather than finding something that everybody's already found and sending me quite a large number of uh emails with pictures on it'd be quite nice to just discount things that are already known but yeah i mean people do send me and i do find new stuff that i hadn't seen before you know it is i've got on my system i think 12 years of different uh aerial photography so going through each one at a time on each field at each location is kind of yeah a bit of a long haul so looking somewhere where you expect it can actually give you a better reward but every now and again someone looks in their back garden which i've never looked at and say have you seen this and you kind of think wow okay and i can set off a whole new train of um examination to see if there's something else there i mean something like the the the belt valley was considered to be no crop marks and yet all around marden it's actually quite rich there's a lot of crop marks there which was unexpected and including some significant enclosures so there was obviously a lot of prehistoric activity in the bell valley that wasn't really known so yeah these things are fun and you've been doing it for a long time now the the developments in technology not just in terms of just being able to to see these satellite photographs and being public access now um there's also drone technology you know if i said to drawing up and do a scan of a an area of you know 15 acres you can do it in about eight minutes and then you can get back and see those results straight away and you don't have to wait for certain uh certain companies to to load them up you can also do it certain times a day when the lights favorable and you got nice long shadows or whatever it might be as well so we can we can get gather more data that way but so there's that technology which must have made a huge difference to what you've been doing but also the the technology in terms of geolocation so geo-referencing those results and as you mentioned earlier when people thought that a villa site or or another building something else archaeological was in a certain place uh and now we have those geo-referenced images that are actually put in the right places um how can how can we can get that information across and how can that benefit the hdr for example well this is quite true i mean there's an awful lot of extremely good uh plans of excavations that happens over time even for some fairly recent time but they don't actually say where if you sort of been i mean we know they're in that field but if you actually have to go back and relocate a section of it or a wall you would have a bit of a fun time doing it because actually we don't actually know in that field where it is it's in that field you know and if unless you prepare to dig a that's like 10 by 10 um bench to try and locate you know sort of a return of a wall uh you know that's that's a big big ask you know so if you've got properly geo-referenced information either from the survey uh i mean from excavation or from properly geocorrected aerial photography you can make that life an awful lot easier you should be able to put in a little three by three and land straight on it in theory we we have this technology of course somewhere we have it the kas we have uh geophysical survey equipment we've got magnetometer uh we have gnss so we can do we can record the locations of trenches that's been found um if there are crop marks or any expectancy or or suspicion that there's an archaeological feature in the landscape uh there are ways and means that we at the ks we can we can help our members and our affiliates to to to investigate those further um obviously with the google maps it's great because you don't have to ask the land owner's permission uh but we're we're obviously far more restricted in that when you get boots on the ground um but yeah i know you've been involved in some of the the survey work we've been doing as well um at least court for example and and and offered as well so how's how is it okay is his equipment and resources helped you out offered in that respect i mean offered it would be as a classic example in the sense that someone did a very good uh resistivity survey over it which dictated where they put the first trial trench in uh because it was over what looked like a return of a uh a building uh they dug the trench and found absolutely nothing that's because the uh trying to get the resistivity meter information back into the real world coordinates proved to be slightly flawed and it was out by about five meters you know and that's the sort of issues that you can have if you uh you know if you if you haven't got proper geo-referenced material to work with so now with the uh gnss we can do several things i mean first of all we can actually relocate um the features properly and so we don't get any possible distortions but also which is equally in terms of upward we can also get levels because we've got a building here that's going up a slope and each room has a slightly different level to the other one and trying to establish the level between the different rooms if you want to do a cross-section saying along one of the ranges that would be quite challenging to do without actually are they getting a theodolite and the old traditional way of doing anything that's a nice bit but hoofing it around i mean you don't stretch the total stations but with the gns s you could just do it in you know you know half an hour you're done you've done the rooms you've done all the levels you've got all the corners you know it's magic almost um and it's the same we used it in bourne to actually create a a very high uh resolution terrain map so we were taking sort of three meter z measurements as we just striding across because it records x and y so you'll be able to generate a a really good dtm from it so yeah in many ways it's a um superb and you say the drone is helpful um drone maps have issues of their own though uh but the problem with aerial photography you're down to pure dumb luck if the as a bloke who had been commissioned to fly it happened to flight at a convenient moment in a convenient place for something you're interested in and i think out of the set of 12 or 13 different years that we've got only about four have crop marks yeah that show up consistency consistently so that's quite a low hit rate you know so and some of them actually show crop marks where they didn't appear in others but most of them are just repetitive you know you always see the same ones uh so drones theoretically should get us around that but getting a drone up at the right time means you've got to see that the croc mark is there which in the game is requires you to actually go down and have a look quite regularly because they appear quite quickly and they disappear even faster yeah your time slots are tricky things to manage and i as you know one that's where i met you actually was at bourne park i was lucky enough to uh to be part of that team that dug the uh the bitter ball park and um it's probably where i really got a big interest in in crop marks and archaeological perspective um and it's some amazing results that they see got those different techniques the gpr and the and the um resistivity um and it must have been really satisfying for you having seen these from the air and then getting them ground truth in that way oh most certainly especially as the first set i saw from the 1990s we sent to a certain archaeological unit who said they were probably from a marquee associated with the uh the uh the cricket pavilion which was a bit of a downer but fortunately uh you know four years on we suddenly discovered of course that there's something else there so that was quite nice to actually find something rather than just be yeah crop marks of a marquee so breaking down them perceptions as well this is probably the same sort of people that say that geophysical survey doesn't work in kent apparently really those beliefs are still held well there are certainly there are certain soil conditions that make it easier shall we say and there are certain sort of conditions that make it a bit of a challenge i mean we have looked ourselves because we looked at the uh i can see the crop marker boxley the shape of the building but we went over it with a mag and saw nothing actually yeah yeah so you don't get a coconut every throw i think is the answer to that yeah absolutely okay well i'm looking through the question and answers we don't have any um live questions from our viewers but still got people attending so um it's uh it'd be great to hear from you if you've got anything to say to chris and so have you got any plans to to target any of those um potential sites that you've been looking at now what's the next stage i think the uh there's some that we've found that uh would certainly benefit from at least in the first instance a field walk over to confirm that the structures i'm seeing are potentially roman in the first instance i mean i've got i mean i mean i've got some definites i'm absolutely convinced i know what they are i've got some that um i'm not sure what that is it could be and those i think particularly be worth the uh visiting if we get an opportunity um well i'm not just i mean roman ones are fine because they're actually tend to be a little bit more obvious [Music] if you've got a very nice enclosure the snag is you can see it's an enclosure but even you actually went and put gf is over it wouldn't necessarily tell you much more than you got an enclosure you know so there's some things that you at the end of the day the only way you're going to get any answers you get the spade out and make a hole yeah yeah you've got to you've got to do it the old-fashioned way well there are plenty of people waiting in on the sidelines after the year and a half that we've had with their buckets and their kneelers and their spades ready to get stuck in absolutely that includes me [Laughter] well um i think we might be planning to do some survey in lee's court this year it's all you know everything's a little bit unsure at the moment so but hopefully we have some low level um sort of investigations there um anything there that's taking your fantasy without being too specific well i think uh 22 corners field i'm fairly sure has an enclosure in it that doesn't look like a ring ditch and doesn't look like the other feature that we've got opposite stringman's he says putting it delicately but the um so that one i think will be very interesting a bit the problem with prehistoric is that uh on the ground it doesn't actually necessarily show you much you know so and the chances of actually just kicking the salt and turning up a chunk of um bronze age pot is pretty slim well that's kind of to some of us that's the allure of the prehistoric archaeology it's the it's the ephemeral nature of it and the unknown going into the unknown yeah there's no other solution as you said yeah get your trowel out and then you find of course it's not bronze age but neolithic what that that'll do for me let me say that okay well um well thanks ever so much for chris giving out your time chris it's um immensely useful and uh as i said in a couple of posts i put out about this it's really for everybody you know we anyone who's got an internet connection can go on to look at these satellite images um and i know that's a there's a lot of people that spend a lot of spare time going over these images and just um thinking you know usually worth writing a lesson to the landowner maybe they'll let me have a walk over and see if i can find anything um maybe more who knows uh but uh it's it's as i say it's extremely uh useful to us to understand more about how this works why these crop masts are there and what they mean so um if there's a if there's anything that anyone's got that they want to send you how would they go about doing so oh they should be able to get my um email address i think for the ks i think i'm up there somewhere okay um it is there isn't it i mean yeah well nice yeah you're on there with your biography okay well um again thanks ever so much and and thanks to everyone who's um watched this video and watched this presentation it means a lot of us a lot to us uh to get your support and as i said there are plenty more coming we will be um getting some more talkers we've got one from rochester cathedral and a couple of other guest um speakers as well but if anybody out there wants to talk about their special subject and take questions and uh from our audience then please get in touch uh you can email me fred burkbeck at communications at kent archaeology.org uk and uh i'll be very happy to hear from anybody who's got any suggestions about that and there will hopefully be some volunteering opportunities uh in the field but there are certainly volunteer opportunities available um to help with some of the functionality and the running and the documents chris is very very heavily involved in our website uh development in terms of loading site reports and other um really important archaeological uh inflammation onto our website we've been building up this database uh that you can search geographically for reports or um studies that have been done in particular areas so we're going to be hopefully hard launching that at some time of the year but we need people who are interested in digitization and helping out with things like that as well so please don't be shy get in touch with us um it will be rewarding uh help us get all this fantastic information about the archaeology and history of kent out to the public and um it will also be something that you will maybe learn some new skills from as well um so please keep in touch and uh keep in tune with our facebook page and the the videos as they get loaded up as well thanks ever so much for taking part and for joining us and we'll see you next time you